翻訳は機械翻訳により提供されています。提供された翻訳内容と英語版の間で齟齬、不一致または矛盾がある場合、英語版が優先します。
# Amazon QLDB Java チュートリアル
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
チュートリアルサンプルアプリケーションのこの実装では、 で Amazon QLDB ドライバーを使用して AWS SDK for Java QLDB 台帳を作成し、サンプルデータを入力します。
このチュートリアルを進めるときは、管理 API オペレーションについて「[AWS SDK for Java API リファレンス](https://docs.aws.amazon.com/sdk-for-java/latest/reference/)」を参照できます。トランザクションデータのオペレーションについては、「[QLDB Driver for Java API Reference](https://javadoc.io/doc/software.amazon.qldb/amazon-qldb-driver-java/latest/index.html)」を参照してください。
**注記**
該当する場合、一部のチュートリアルステップでは、サポートされているメジャーバージョンの Java 用 QLDB ドライバーに対して異なるコマンドまたはコード例があります。
**Topics**
+ [
# Amazon QLDB Java サンプルアプリケーションのインストール
](sample-app.java.md)
+ [
# ステップ 1: 新しい台帳を作成する
](getting-started.java.step-1.md)
+ [
# ステップ 2: 台帳への接続をテストする
](getting-started.java.step-2.md)
+ [
# ステップ 3: テーブル、インデックス、およびサンプルデータを作成する
](getting-started.java.step-3.md)
+ [
# ステップ 4: 台帳のテーブルにクエリを実行する
](getting-started.java.step-4.md)
+ [
# ステップ 5: 台帳内のドキュメントを変更する
](getting-started.java.step-5.md)
+ [
# ステップ 6: ドキュメントのリビジョン履歴を表示する
](getting-started.java.step-6.md)
+ [
# ステップ 7: 台帳内のドキュメントを検証する
](getting-started.java.step-7.md)
+ [
# ステップ 8: 元帳のジャーナルデータをエクスポートして検証する
](getting-started.java.step-8.md)
+ [
# ステップ 9 (オプション): リソースをクリーンアップする
](getting-started.java.step-9.md)
# Amazon QLDB Java サンプルアプリケーションのインストール
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
このセクションでは、ステップバイステップの Java チュートリアル用に提供されている Amazon QLDB サンプルアプリケーションをインストールして実行する方法について説明します。このサンプルアプリケーションのユースケースは、車両登録に関する完全な履歴情報を追跡する自動車部門 (DMV) データベースです。
Java 用の DMV サンプルアプリケーションは、GitHub リポジトリ [aws-samples/amazon-qldb-dmv-sample-java](https://github.com/aws-samples/amazon-qldb-dmv-sample-java) でオープンソースとして公開されています。
## 前提条件
開始する前に、Java 用 QLDB ドライバーの「[前提条件](getting-started.java.md#getting-started.java.prereqs)」を完了していることを確認します。これには以下が含まれます。
1. にサインアップします AWS。
1. QLDB の適切なアクセス許可を持つユーザーを作成します。このチュートリアルのすべての手順を完了するには、QLDB API を介して台帳リソースへのフル管理アクセス権が必要です。
1. 以外の IDE を使用している場合は AWS Cloud9、Java をインストールし、開発用のプログラムによるアクセスを許可します。
## インストール
以下のステップでは、ローカル開発環境でサンプルアプリケーションをダウンロードして設定する方法について説明します。または、 を IDE AWS Cloud9 として使用し、 CloudFormation テンプレートを使用して開発リソースをプロビジョニングすることで、サンプルアプリケーションのセットアップを自動化することもできます。
### ローカルの開発環境
ここでは、独自のリソースと開発環境を使用して QLDB Java サンプルアプリケーションをダウンロードしてインストールする方法について説明します。
**サンプルアプリケーションをダウンロードして実行するには**
1. 次のコマンドを入力して、GitHub からサンプルアプリケーションのクローンを作成します。
------
#### [ 2.x ]
```
git clone https://github.com/aws-samples/amazon-qldb-dmv-sample-java.git
```
------
#### [ 1.x ]
```
git clone -b v1.2.0 https://github.com/aws-samples/amazon-qldb-dmv-sample-java.git
```
------
このパッケージには、Gradle 設定と [Java チュートリアル](getting-started.java.tutorial.md) からの完全なコードが含まれています。
1. 提供されたアプリケーションをロードして実行します。
+ Eclipse を使用している場合:
1. Eclipse を起動し、[**Eclipse**] メニューで、[**File (ファイル)**]、[**Import (インポート)**]、[**Existing Gradle Project (既存の Gradle プロジェクト)**] の順に選択します。
1. プロジェクトのルートディレクトリで、`build.gradle` ファイルが格納されているアプリケーションディレクトリを参照して選択します。次に、[**Finish (完了)**] を選択し、インポートにデフォルトの Gradle 設定を使用します。
1. 例として `ListLedgers` プログラムを実行してみることができます。`ListLedgers.java` ファイルのコンテキスト (右クリック) メニューを開き、[**Run as Java Application (Java アプリケーションとして実行)**] を選択します。
+ IntelliJ を使用している場合:
1. IntelliJ を起動し、[**IntelliJ**] メニューで [**File (ファイル)**]、[**Open (開く)**] の順に選択します。
1. プロジェクトのルートディレクトリで、`build.gradle` ファイルが格納されているアプリケーションディレクトリを参照して選択します。次に、[**OK**] を選択します。デフォルト設定をそのままにして、[**OK**] を再び選択します。
1. 例として `ListLedgers` プログラムを実行してみることができます。`ListLedgers.java` ファイルのコンテキスト (右クリック) メニューを開き、[**Run 'ListLedgers' (「ListLedgers」として実行)**] を選択します。
1. [ステップ 1: 新しい台帳を作成する](getting-started.java.step-1.md) に進み、チュートリアルを開始して台帳を作成します。
### AWS Cloud9
以下の手順では、[AWS Cloud9](https://aws.amazon.com/cloud9) を IDE として使用して Java 用の Amazon QLDB 車両登録サンプルアプリケーションのセットアップを自動化する方法について説明します。このガイドでは、[CloudFormation](https://aws.amazon.com/cloudformation) テンプレートを使用して、開発リソースをプロビジョニングします。
詳細については AWS Cloud9、「 [AWS Cloud9 ユーザーガイド](https://docs.aws.amazon.com/cloud9/latest/user-guide/)」を参照してください。 CloudFormationの詳細については、「[AWS CloudFormation ユーザーガイド](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/)」を参照してください。
**Topics**
+ [
#### パート 1: リソースのプロビジョニング
](#sample-app.java.cfn-ac9.step-1)
+ [
#### パート 2: IDE をセットアップする
](#sample-app.java.cfn-ac9.step-2)
+ [
#### パート 3: QLDB DMV サンプルアプリケーションを実行する
](#sample-app.java.cfn-ac9.step-3)
#### パート 1: リソースのプロビジョニング
この最初のステップでは、 CloudFormation を使用して、Amazon QLDB サンプルアプリケーションで開発環境をセットアップするために必要なリソースをプロビジョニングします。
**CloudFormation コンソールを開き、QLDB サンプルアプリケーションテンプレートをロードするには**
1. にサインイン AWS マネジメントコンソール し、[https://console.aws.amazon.com/cloudformation](https://console.aws.amazon.com/cloudformation/) で CloudFormation コンソールを開きます。
QLDB をサポートするリージョンに切り替えます。完全なリストについては、「AWS 全般のリファレンス」の「[Amazon QLDB エンドポイントとクォータ](https://docs.aws.amazon.com/general/latest/gr/qldb.html)」を参照してください。次の のスクリーンショット AWS マネジメントコンソール は、米国東部 (バージニア北部) が選択されています AWS リージョン。
![\[AWS マネジメントコンソール 選択した として米国東部 (バージニア北部) を表示 AWS リージョンしています。\]](http://docs.aws.amazon.com/ja_jp/qldb/latest/developerguide/images/cfn-ac9/aws-region-us-east-1.png)
1. CloudFormation コンソールで、**スタックの作成**を選択し、**新しいリソース (標準) **で を選択します。
1. [**Create stack (スタックの作成)**] ページの [**Specify template (テンプレートの指定)**] で、[**Amazon S3 URL**] を選択します。
1. 次の URL を入力し、[**Next (次へ)**] を選択します。
```
https://amazon-qldb-assets.s3.amazonaws.com/templates/QLDB-DMV-SampleApp.yml
```
1. [**Stack name (スタック名)**] (**qldb-sample-app** など) を入力し、[**Next (次へ)**] を選択します。
1. 必要に応じてタグを追加し、デフォルトのオプションはそのままにしておきます。次いで、**[次へ]** を選択します。
1. スタックの設定を確認し、[**Create stack (スタックの作成)**] を選択します。 CloudFormation スクリプトが終了するまでに数分かかる場合があります。
このスクリプトは、このチュートリアルで QLDB サンプルアプリケーションの実行に使用する、関連付けられた Amazon Elastic Compute Cloud (Amazon EC2) インスタンスを AWS Cloud9 環境をプロビジョニングします。また、[aws-samples/amazon-qldb-dmv-sample-java](https://github.com/aws-samples/amazon-qldb-dmv-sample-java/) リポジトリを GitHub から AWS Cloud9 開発環境にクローンします。
#### パート 2: IDE をセットアップする
このステップでは、クラウド開発環境のセットアップを完了します。提供されているシェルスクリプトをダウンロードして実行し、サンプルアプリケーションの依存関係を使用して AWS Cloud9 IDE を設定します。
**AWS Cloud9 環境を設定するには**
1. [https://console.aws.amazon.com/cloud9/](https://console.aws.amazon.com/cloud9/) で AWS Cloud9 コンソールを開きます。
1. [**Your environments (環境)**] で、**QLDB DMV Sample Application** という名前の環境のカードを探し、[**Open IDE (IDE を開く)**] を選択します。お使いの環境によっては、基盤となる EC2 インスタンスが起動する際、ロードに時間がかかる場合があります。
AWS Cloud9 環境は、チュートリアルの実行に必要なシステムの依存関係で事前設定されています。コンソールの [**Environment (環境)**] ナビゲーションペインで、`QLDB DMV Sample Application` という名前のフォルダが表示されていることを確認します。次の AWS Cloud9 コンソールのスクリーンショットは、QLDB DMV サンプルアプリケーション環境フォルダペインを示しています。
![\[AWS Cloud9 QLDB DMV サンプルアプリケーション環境フォルダペインを示す コンソール。\]](http://docs.aws.amazon.com/ja_jp/qldb/latest/developerguide/images/cfn-ac9/cloud9-folders.png)
ナビゲーションペインが表示されない場合は、コンソールの左側にある [**Environment (環境)**] タブを切り替えます。ペインにフォルダが全く表示されない場合は、設定アイコン (![\[Settings icon\]](http://docs.aws.amazon.com/ja_jp/qldb/latest/developerguide/images/settings.png)) を使用して **[Show Environment Root]** (環境ルートの表示) を有効にします。
1. コンソールの下部のペインに、`bash` ターミナルウィンドウが開かれます。これが表示されない場合は、コンソール上部にある **[Window]** (ウィンドウ) メニューから **[New Terminal]** (新しいターミナル) を選択します。
1. 次に、セットアップスクリプトをダウンロードして実行して OpenJDK 8 をインストールし、該当する場合は Git リポジトリから適切なブランチをチェックアウトします。前のステップで作成した AWS Cloud9 ターミナルで、次の 2 つのコマンドを順番に実行します。
------
#### [ 2.x ]
```
aws s3 cp s3://amazon-qldb-assets/setup-scripts/dmv-setup-v2.sh .
```
```
sh dmv-setup-v2.sh
```
------
#### [ 1.x ]
```
aws s3 cp s3://amazon-qldb-assets/setup-scripts/dmv-setup.sh .
```
```
sh dmv-setup.sh
```
------
完了すると、ターミナルに次のメッセージが表示されます。
```
** DMV Sample App setup completed , enjoy!! **
```
1. でサンプルアプリケーションコードを参照します。 AWS Cloud9特にディレクトリパス で参照します`src/main/java/software/amazon/qldb/tutorial`。
#### パート 3: QLDB DMV サンプルアプリケーションを実行する
このステップでは、 を使用して Amazon QLDB DMV サンプルアプリケーションタスクを実行する方法について説明します AWS Cloud9。サンプルコードを実行するには、 AWS Cloud9 ターミナルに戻るか、*パート 2: IDE のセットアップ*で行ったように新しいターミナルウィンドウを作成します。
**サンプルアプリケーションを実行するには**
1. ターミナルで次のコマンドを実行し、プロジェクトのルートディレクトリに切り替えます。
```
cd ~/environment/amazon-qldb-dmv-sample-java
```
次のディレクトリパスの例を実行していることを確認します。
```
/home/ec2-user/environment/amazon-qldb-dmv-sample-java/
```
1. 次のコマンドは、各タスクを実行するための Gradle 構文を示します。
```
./gradlew run -Dtutorial=Task
```
例えば、次のコマンドを実行して、 AWS アカウント と現在のリージョンのすべての台帳を一覧表示します。
```
./gradlew run -Dtutorial=ListLedgers
```
1. [ステップ 1: 新しい台帳を作成する](getting-started.java.step-1.md) に進み、チュートリアルを開始して台帳を作成します。
1. (オプション) このチュートリアルを完了した後、不要になった CloudFormation リソースをクリーンアップします。
1. [https://console.aws.amazon.com/cloudformation](https://console.aws.amazon.com/cloudformation/) で CloudFormation コンソールを開き、*パート 1: リソースのプロビジョニング*で作成したスタックを削除します。
1. また、 CloudFormation テンプレートが作成した AWS Cloud9 スタックも削除します。
# ステップ 1: 新しい台帳を作成する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
このステップでは、`vehicle-registration` という名前の新しい Amazon QLDB 台帳を作成します。
**新しい台帳を作成するには**
1. 次のファイル (`Constants.java`) を確認します。このファイルには、このチュートリアル内の他のすべてのプログラムで使用される定数値が含まれています。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonSystem;
import com.amazon.ion.system.IonSystemBuilder;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.dataformat.ion.IonObjectMapper;
import com.fasterxml.jackson.dataformat.ion.ionvalue.IonValueMapper;
/**
* Constant values used throughout this tutorial.
*/
public final class Constants {
public static final int RETRY_LIMIT = 4;
public static final String LEDGER_NAME = "vehicle-registration";
public static final String STREAM_NAME = "vehicle-registration-stream";
public static final String VEHICLE_REGISTRATION_TABLE_NAME = "VehicleRegistration";
public static final String VEHICLE_TABLE_NAME = "Vehicle";
public static final String PERSON_TABLE_NAME = "Person";
public static final String DRIVERS_LICENSE_TABLE_NAME = "DriversLicense";
public static final String VIN_INDEX_NAME = "VIN";
public static final String PERSON_GOV_ID_INDEX_NAME = "GovId";
public static final String VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME = "LicensePlateNumber";
public static final String DRIVER_LICENSE_NUMBER_INDEX_NAME = "LicenseNumber";
public static final String DRIVER_LICENSE_PERSONID_INDEX_NAME = "PersonId";
public static final String JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX = "qldb-tutorial-journal-export";
public static final String USER_TABLES = "information_schema.user_tables";
public static final String LEDGER_NAME_WITH_TAGS = "tags";
public static final IonSystem SYSTEM = IonSystemBuilder.standard().build();
public static final IonObjectMapper MAPPER = new IonValueMapper(SYSTEM);
private Constants() { }
static {
MAPPER.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
}
}
```
------
#### [ 1.x ]
**重要**
Amazon Ion パッケージの場合、アプリケーションで名前空間 `com.amazon.ion` を使用する必要があります。 AWS SDK for Java は、名前空間 の別の Ion パッケージに依存しますが`software.amazon.ion`、これは QLDB ドライバーと互換性のないレガシーパッケージです。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonSystem;
import com.amazon.ion.system.IonSystemBuilder;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.dataformat.ion.IonObjectMapper;
import com.fasterxml.jackson.dataformat.ion.ionvalue.IonValueMapper;
/**
* Constant values used throughout this tutorial.
*/
public final class Constants {
public static final int RETRY_LIMIT = 4;
public static final String LEDGER_NAME = "vehicle-registration";
public static final String STREAM_NAME = "vehicle-registration-stream";
public static final String VEHICLE_REGISTRATION_TABLE_NAME = "VehicleRegistration";
public static final String VEHICLE_TABLE_NAME = "Vehicle";
public static final String PERSON_TABLE_NAME = "Person";
public static final String DRIVERS_LICENSE_TABLE_NAME = "DriversLicense";
public static final String VIN_INDEX_NAME = "VIN";
public static final String PERSON_GOV_ID_INDEX_NAME = "GovId";
public static final String VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME = "LicensePlateNumber";
public static final String DRIVER_LICENSE_NUMBER_INDEX_NAME = "LicenseNumber";
public static final String DRIVER_LICENSE_PERSONID_INDEX_NAME = "PersonId";
public static final String JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX = "qldb-tutorial-journal-export";
public static final String USER_TABLES = "information_schema.user_tables";
public static final String LEDGER_NAME_WITH_TAGS = "tags";
public static final IonSystem SYSTEM = IonSystemBuilder.standard().build();
public static final IonObjectMapper MAPPER = new IonValueMapper(SYSTEM);
private Constants() { }
static {
MAPPER.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
}
}
```
------
**注記**
この `Constants` クラスには、オープンソースの Jackson `IonValueMapper` クラスのインスタンスが含まれています。このマッパーを使用して、読み取りおよび書き込みトランザクションを実行するときに [Amazon Ion](ion.md) データを処理できます。
`CreateLedger.java` ファイルには、台帳の現在のステータスを説明する次のプログラム (`DescribeLedger.java`) にも依存しています。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.model.DescribeLedgerRequest;
import com.amazonaws.services.qldb.model.DescribeLedgerResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Describe a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class DescribeLedger {
public static AmazonQLDB client = CreateLedger.getClient();
public static final Logger log = LoggerFactory.getLogger(DescribeLedger.class);
private DescribeLedger() { }
public static void main(final String... args) {
try {
describe(Constants.LEDGER_NAME);
} catch (Exception e) {
log.error("Unable to describe a ledger!", e);
}
}
/**
* Describe a ledger.
*
* @param name
* Name of the ledger to describe.
* @return {@link DescribeLedgerResult} from QLDB.
*/
public static DescribeLedgerResult describe(final String name) {
log.info("Let's describe ledger with name: {}...", name);
DescribeLedgerRequest request = new DescribeLedgerRequest().withName(name);
DescribeLedgerResult result = client.describeLedger(request);
log.info("Success. Ledger description: {}", result);
return result;
}
}
```
1. `CreateLedger.java` プログラムをコンパイルして実行し、`vehicle-registration` という名前の台帳を作成します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.client.builder.AwsClientBuilder;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.AmazonQLDBClientBuilder;
import com.amazonaws.services.qldb.model.CreateLedgerRequest;
import com.amazonaws.services.qldb.model.CreateLedgerResult;
import com.amazonaws.services.qldb.model.DescribeLedgerResult;
import com.amazonaws.services.qldb.model.LedgerState;
import com.amazonaws.services.qldb.model.PermissionsMode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Create a ledger and wait for it to be active.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class CreateLedger {
public static final Logger log = LoggerFactory.getLogger(CreateLedger.class);
public static final Long LEDGER_CREATION_POLL_PERIOD_MS = 10_000L;
public static String endpoint = null;
public static String region = null;
public static AmazonQLDB client = getClient();
private CreateLedger() {
}
/**
* Build a low-level QLDB client.
*
* @return {@link AmazonQLDB} control plane client.
*/
public static AmazonQLDB getClient() {
AmazonQLDBClientBuilder builder = AmazonQLDBClientBuilder.standard();
if (null != endpoint && null != region) {
builder.setEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration(endpoint, region));
}
return builder.build();
}
public static void main(final String... args) throws Exception {
try {
client = getClient();
create(Constants.LEDGER_NAME);
waitForActive(Constants.LEDGER_NAME);
} catch (Exception e) {
log.error("Unable to create the ledger!", e);
throw e;
}
}
/**
* Create a new ledger with the specified ledger name.
*
* @param ledgerName Name of the ledger to be created.
* @return {@link CreateLedgerResult} from QLDB.
*/
public static CreateLedgerResult create(final String ledgerName) {
log.info("Let's create the ledger with name: {}...", ledgerName);
CreateLedgerRequest request = new CreateLedgerRequest()
.withName(ledgerName)
.withPermissionsMode(PermissionsMode.ALLOW_ALL);
CreateLedgerResult result = client.createLedger(request);
log.info("Success. Ledger state: {}.", result.getState());
return result;
}
/**
* Wait for a newly created ledger to become active.
*
* @param ledgerName Name of the ledger to wait on.
* @return {@link DescribeLedgerResult} from QLDB.
* @throws InterruptedException if thread is being interrupted.
*/
public static DescribeLedgerResult waitForActive(final String ledgerName) throws InterruptedException {
log.info("Waiting for ledger to become active...");
while (true) {
DescribeLedgerResult result = DescribeLedger.describe(ledgerName);
if (result.getState().equals(LedgerState.ACTIVE.name())) {
log.info("Success. Ledger is active and ready to use.");
return result;
}
log.info("The ledger is still creating. Please wait...");
Thread.sleep(LEDGER_CREATION_POLL_PERIOD_MS);
}
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.AmazonQLDBClientBuilder;
import com.amazonaws.services.qldb.model.CreateLedgerRequest;
import com.amazonaws.services.qldb.model.CreateLedgerResult;
import com.amazonaws.services.qldb.model.DescribeLedgerResult;
import com.amazonaws.services.qldb.model.LedgerState;
import com.amazonaws.services.qldb.model.PermissionsMode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Create a ledger and wait for it to be active.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class CreateLedger {
public static final Logger log = LoggerFactory.getLogger(CreateLedger.class);
public static final Long LEDGER_CREATION_POLL_PERIOD_MS = 10_000L;
public static AmazonQLDB client = getClient();
private CreateLedger() { }
/**
* Build a low-level QLDB client.
*
* @return {@link AmazonQLDB} control plane client.
*/
public static AmazonQLDB getClient() {
return AmazonQLDBClientBuilder.standard().build();
}
public static void main(final String... args) throws Exception {
try {
create(Constants.LEDGER_NAME);
waitForActive(Constants.LEDGER_NAME);
} catch (Exception e) {
log.error("Unable to create the ledger!", e);
throw e;
}
}
/**
* Create a new ledger with the specified ledger name.
*
* @param ledgerName
* Name of the ledger to be created.
* @return {@link CreateLedgerResult} from QLDB.
*/
public static CreateLedgerResult create(final String ledgerName) {
log.info("Let's create the ledger with name: {}...", ledgerName);
CreateLedgerRequest request = new CreateLedgerRequest()
.withName(ledgerName)
.withPermissionsMode(PermissionsMode.ALLOW_ALL);
CreateLedgerResult result = client.createLedger(request);
log.info("Success. Ledger state: {}.", result.getState());
return result;
}
/**
* Wait for a newly created ledger to become active.
*
* @param ledgerName
* Name of the ledger to wait on.
* @return {@link DescribeLedgerResult} from QLDB.
* @throws InterruptedException if thread is being interrupted.
*/
public static DescribeLedgerResult waitForActive(final String ledgerName) throws InterruptedException {
log.info("Waiting for ledger to become active...");
while (true) {
DescribeLedgerResult result = DescribeLedger.describe(ledgerName);
if (result.getState().equals(LedgerState.ACTIVE.name())) {
log.info("Success. Ledger is active and ready to use.");
return result;
}
log.info("The ledger is still creating. Please wait...");
Thread.sleep(LEDGER_CREATION_POLL_PERIOD_MS);
}
}
}
```
------
**注記**
`createLedger` の呼び出しで、台帳名とアクセス許可モードを指定する必要があります。台帳データのセキュリティを最大化する、`STANDARD` のアクセス許可モードの使用を推奨します。
台帳を作成すると、デフォルトで*削除保護*が有効になります。これは QLDB の機能であり、ユーザーによって台帳が削除されるのを防ぎます。QLDB API または AWS Command Line Interface () を使用して、台帳の作成時に削除保護を無効にするオプションがありますAWS CLI。
必要に応じて、台帳にアタッチするタグを指定することもできます。
新しい台帳への接続を確認するには、「[ステップ 2: 台帳への接続をテストする](getting-started.java.step-2.md)」に進みます。
# ステップ 2: 台帳への接続をテストする
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
このステップでは、トランザクションデータ API エンドポイントを使用して Amazon QLDB の `vehicle-registration` 台帳に接続できることを確認します。
**台帳への接続をテストするには**
1. 以下のプログラム (`ConnectToLedger.java`) を確認します。このプログラムは、`vehicle-registration` 台帳へのデータセッション接続を作成します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.net.URI;
import java.net.URISyntaxException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider;
import software.amazon.awssdk.services.qldbsession.QldbSessionClient;
import software.amazon.awssdk.services.qldbsession.QldbSessionClientBuilder;
import software.amazon.qldb.QldbDriver;
import software.amazon.qldb.RetryPolicy;
/**
* Connect to a session for a given ledger using default settings.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class ConnectToLedger {
public static final Logger log = LoggerFactory.getLogger(ConnectToLedger.class);
public static AwsCredentialsProvider credentialsProvider;
public static String endpoint = null;
public static String ledgerName = Constants.LEDGER_NAME;
public static String region = null;
public static QldbDriver driver;
private ConnectToLedger() {
}
/**
* Create a pooled driver for creating sessions.
*
* @param retryAttempts How many times the transaction will be retried in
* case of a retryable issue happens like Optimistic Concurrency Control exception,
* server side failures or network issues.
* @return The pooled driver for creating sessions.
*/
public static QldbDriver createQldbDriver(int retryAttempts) {
QldbSessionClientBuilder builder = getAmazonQldbSessionClientBuilder();
return QldbDriver.builder()
.ledger(ledgerName)
.transactionRetryPolicy(RetryPolicy
.builder()
.maxRetries(retryAttempts)
.build())
.sessionClientBuilder(builder)
.build();
}
/**
* Create a pooled driver for creating sessions.
*
* @return The pooled driver for creating sessions.
*/
public static QldbDriver createQldbDriver() {
QldbSessionClientBuilder builder = getAmazonQldbSessionClientBuilder();
return QldbDriver.builder()
.ledger(ledgerName)
.transactionRetryPolicy(RetryPolicy.builder()
.maxRetries(Constants.RETRY_LIMIT).build())
.sessionClientBuilder(builder)
.build();
}
/**
* Creates a QldbSession builder that is passed to the QldbDriver to connect to the Ledger.
*
* @return An instance of the AmazonQLDBSessionClientBuilder
*/
public static QldbSessionClientBuilder getAmazonQldbSessionClientBuilder() {
QldbSessionClientBuilder builder = QldbSessionClient.builder();
if (null != endpoint && null != region) {
try {
builder.endpointOverride(new URI(endpoint));
} catch (URISyntaxException e) {
throw new IllegalArgumentException(e);
}
}
if (null != credentialsProvider) {
builder.credentialsProvider(credentialsProvider);
}
return builder;
}
/**
* Create a pooled driver for creating sessions.
*
* @return The pooled driver for creating sessions.
*/
public static QldbDriver getDriver() {
if (driver == null) {
driver = createQldbDriver();
}
return driver;
}
public static void main(final String... args) {
Iterable tables = ConnectToLedger.getDriver().getTableNames();
log.info("Existing tables in the ledger:");
for (String table : tables) {
log.info("- {} ", table);
}
}
}
```
**注記**
台帳に対してデータオペレーションを実行するには、`QldbDriver` クラスのインスタンスを作成して、特定の台帳に接続する必要があります。これは、前のステップで台帳の作成に使用した `AmazonQLDB` クライアントとは異なるクライアントオブジェクトです。前のクライアントは、「[Amazon QLDB API リファレンス](api-reference.md)」に示されている管理 API オペレーションの実行にのみ使用されます。
まず、`QldbDriver` オブジェクトを作成します。このドライバーを作成するときに台帳名を指定する必要があります。
次に、このドライバーの `execute` メソッドを使用して、PartiQL ステートメントを実行できます。
オプションで、トランザクション例外の最大再試行回数を指定できます。`execute` メソッドは、オプティミスティック同時実行制御 (OCC、optimistic concurrency control) の競合やその他の一般的な一時例外を、この設定可能な制限に達するまで自動的に再試行します。デフォルト値は `4` です。
この制限に達した後もトランザクションが成功しない場合、ドライバーが例外をスローします。詳細については、「[Amazon QLDB でドライバーが使用する再試行ポリシーを理解する](driver-retry-policy.md)」を参照してください。
------
#### [ 1.x ]
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.auth.AWSCredentialsProvider;
import com.amazonaws.client.builder.AwsClientBuilder;
import com.amazonaws.services.qldbsession.AmazonQLDBSessionClientBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.PooledQldbDriver;
import software.amazon.qldb.QldbDriver;
import software.amazon.qldb.QldbSession;
import software.amazon.qldb.exceptions.QldbClientException;
/**
* Connect to a session for a given ledger using default settings.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class ConnectToLedger {
public static final Logger log = LoggerFactory.getLogger(ConnectToLedger.class);
public static AWSCredentialsProvider credentialsProvider;
public static String endpoint = null;
public static String ledgerName = Constants.LEDGER_NAME;
public static String region = null;
private static PooledQldbDriver driver;
private ConnectToLedger() {
}
/**
* Create a pooled driver for creating sessions.
*
* @return The pooled driver for creating sessions.
*/
public static PooledQldbDriver createQldbDriver() {
AmazonQLDBSessionClientBuilder builder = AmazonQLDBSessionClientBuilder.standard();
if (null != endpoint && null != region) {
builder.setEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration(endpoint, region));
}
if (null != credentialsProvider) {
builder.setCredentials(credentialsProvider);
}
return PooledQldbDriver.builder()
.withLedger(ledgerName)
.withRetryLimit(Constants.RETRY_LIMIT)
.withSessionClientBuilder(builder)
.build();
}
/**
* Create a pooled driver for creating sessions.
*
* @return The pooled driver for creating sessions.
*/
public static PooledQldbDriver getDriver() {
if (driver == null) {
driver = createQldbDriver();
}
return driver;
}
/**
* Connect to a ledger through a {@link QldbDriver}.
*
* @return {@link QldbSession}.
*/
public static QldbSession createQldbSession() {
return getDriver().getSession();
}
public static void main(final String... args) {
try (QldbSession qldbSession = createQldbSession()) {
log.info("Listing table names ");
for (String tableName : qldbSession.getTableNames()) {
log.info(tableName);
}
} catch (QldbClientException e) {
log.error("Unable to create session.", e);
}
}
}
```
**注記**
台帳に対してデータオペレーションを実行するには、`PooledQldbDriver` または `QldbDriver` クラスのインスタンスを作成して、特定の台帳に接続する必要があります。これは、前のステップで台帳の作成に使用した `AmazonQLDB` クライアントとは異なるクライアントオブジェクトです。前のクライアントは、「[Amazon QLDB API リファレンス](api-reference.md)」に示されている管理 API オペレーションの実行にのみ使用されます。
`QldbDriver` でカスタムセッションプールを実装する必要がない限り、`PooledQldbDriver` を使用することをお勧めします。`PooledQldbDriver` のデフォルトプールサイズは、セッションクライアントが許可する[開いている HTTP 接続の最大数](https://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/ClientConfiguration.html#getMaxConnections--)です。
まず、`PooledQldbDriver` オブジェクトを作成します。このドライバーを作成するときに台帳名を指定する必要があります。
次に、このドライバーの `execute` メソッドを使用して、PartiQL ステートメントを実行できます。または、このプールされたドライバーオブジェクトから手動でセッションを作成し、セッションの `execute` メソッドを使用することもできます。セッションは、台帳との 1 つの接続を表します。
オプションで、トランザクション例外の最大再試行回数を指定できます。`execute` メソッドは、オプティミスティック同時実行制御 (OCC、optimistic concurrency control) の競合やその他の一般的な一時例外を、この設定可能な制限に達するまで自動的に再試行します。デフォルト値は `4` です。
この制限に達した後もトランザクションが成功しない場合、ドライバーが例外をスローします。詳細については、「[Amazon QLDB でドライバーが使用する再試行ポリシーを理解する](driver-retry-policy.md)」を参照してください。
------
1. `ConnectToLedger.java` プログラムをコンパイルし実行して、`vehicle-registration` 台帳へのデータセッション接続をテストします。
**の上書き AWS リージョン**
サンプルアプリケーションは、デフォルトの QLDB に接続します。これは AWS リージョン、前提条件のステップ で説明されているように設定できます[デフォルトの AWS の認証情報とリージョンを設定する](getting-started.java.md#getting-started.java.credentials)。QLDB セッションクライアントビルダープロパティを変更することで、リージョンを変更することもできます。
------
#### [ 2.x ]
次のサンプルコードは、新しい `QldbSessionClientBuilder` オブジェクトをインスタンス化します。
```
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.qldbsession.QldbSessionClientBuilder;
// This client builder will default to US East (Ohio)
QldbSessionClientBuilder builder = QldbSessionClient.builder()
.region(Region.US_EAST_2);
```
`region` メソッドを使用して、利用可能な任意のリージョンで、QLDB を対象としてコードを実行できます。完全なリストについては、「AWS 全般のリファレンス」の「[Amazon QLDB エンドポイントとクォータ](https://docs.aws.amazon.com/general/latest/gr/qldb.html)」を参照してください。
------
#### [ 1.x ]
次のサンプルコードは、新しい `AmazonQLDBSessionClientBuilder` オブジェクトをインスタンス化します。
```
import com.amazonaws.regions.Regions;
import com.amazonaws.services.qldbsession.AmazonQLDBSessionClientBuilder;
// This client builder will default to US East (Ohio)
AmazonQLDBSessionClientBuilder builder = AmazonQLDBSessionClientBuilder.standard()
.withRegion(Regions.US_EAST_2);
```
`withRegion` メソッドを使用して、利用可能な任意のリージョンで、QLDB を対象としてコードを実行できます。完全なリストについては、「AWS 全般のリファレンス」の「[Amazon QLDB エンドポイントとクォータ](https://docs.aws.amazon.com/general/latest/gr/qldb.html)」を参照してください。
------
`vehicle-registration` 台帳にテーブルを作成するには、「[ステップ 3: テーブル、インデックス、およびサンプルデータを作成する](getting-started.java.step-3.md)」に進みます。
# ステップ 3: テーブル、インデックス、およびサンプルデータを作成する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
Amazon QLDB 台帳がアクティブになり、接続を受け入れると、車両、車両の所有者、登録情報に関するデータのテーブルを作成できるようになります。テーブルとインデックスを作成した後、これらにデータをロードできます。
このステップでは、`vehicle-registration` 台帳に 4 つのテーブルを作成します。
+ `VehicleRegistration`
+ `Vehicle`
+ `Person`
+ `DriversLicense`
以下のインデックスも作成します。
****
| テーブル名 | フィールド |
| --- | --- |
| VehicleRegistration | VIN |
| VehicleRegistration | LicensePlateNumber |
| Vehicle | VIN |
| Person | GovId |
| DriversLicense | LicenseNumber |
| DriversLicense | PersonId |
サンプルデータを挿入するときは、まず `Person` テーブルにドキュメントを挿入します。次に、各 `Person` ドキュメントからシステムによって割り当てられた `id` を使用して、適切な `VehicleRegistration` および `DriversLicense` ドキュメントの対応するフィールドに入力します。
**ヒント**
ベストプラクティスとして、外部キーには、ドキュメントにシステムによって割り当てられた `id` を使用します。一意の識別子 (車両の VIN など) 用にフィールドを定義することはできますが、実際のドキュメントの一意の識別子はその `id` です。このフィールドはドキュメントのメタデータに含まれており、コミット済みビュー (*テーブルのシステム定義のビュー*) でクエリを実行できます。
QLDB におけるビューの詳細については、「[重要な概念](ledger-structure.md)」を参照してください。メタデータの詳細については、「[ドキュメントのメタデータのクエリの実行](working.metadata.md)」を参照してください。
**サンプルデータを設定するには**
1. 以下の `.java` ファイルを確認します。これらのモデルクラスは、`vehicle-registration` テーブルに保存するドキュメントを表します。Amazon Ion 形式との間でシリアル化されます。
**注記**
[Amazon QLDB のドキュメント](ql-reference.docs.md) は、 JSON のスーパーセットであるIon フォーマットで保存されます。したがって、FasterXML Jackson ライブラリを使用して、JSON でデータをモデル化できます。
1. `DriversLicense.java`
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import software.amazon.qldb.tutorial.model.streams.RevisionData;
import java.time.LocalDate;
/**
* Represents a driver's license, serializable to (and from) Ion.
*/
public final class DriversLicense implements RevisionData {
private final String personId;
private final String licenseNumber;
private final String licenseType;
@JsonSerialize(using = IonLocalDateSerializer.class)
@JsonDeserialize(using = IonLocalDateDeserializer.class)
private final LocalDate validFromDate;
@JsonSerialize(using = IonLocalDateSerializer.class)
@JsonDeserialize(using = IonLocalDateDeserializer.class)
private final LocalDate validToDate;
@JsonCreator
public DriversLicense(@JsonProperty("PersonId") final String personId,
@JsonProperty("LicenseNumber") final String licenseNumber,
@JsonProperty("LicenseType") final String licenseType,
@JsonProperty("ValidFromDate") final LocalDate validFromDate,
@JsonProperty("ValidToDate") final LocalDate validToDate) {
this.personId = personId;
this.licenseNumber = licenseNumber;
this.licenseType = licenseType;
this.validFromDate = validFromDate;
this.validToDate = validToDate;
}
@JsonProperty("PersonId")
public String getPersonId() {
return personId;
}
@JsonProperty("LicenseNumber")
public String getLicenseNumber() {
return licenseNumber;
}
@JsonProperty("LicenseType")
public String getLicenseType() {
return licenseType;
}
@JsonProperty("ValidFromDate")
public LocalDate getValidFromDate() {
return validFromDate;
}
@JsonProperty("ValidToDate")
public LocalDate getValidToDate() {
return validToDate;
}
@Override
public String toString() {
return "DriversLicense{" +
"personId='" + personId + '\'' +
", licenseNumber='" + licenseNumber + '\'' +
", licenseType='" + licenseType + '\'' +
", validFromDate=" + validFromDate +
", validToDate=" + validToDate +
'}';
}
}
```
1. `Person.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import java.time.LocalDate;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.Constants;
import software.amazon.qldb.tutorial.model.streams.RevisionData;
/**
* Represents a person, serializable to (and from) Ion.
*/
public final class Person implements RevisionData {
private final String firstName;
private final String lastName;
@JsonSerialize(using = IonLocalDateSerializer.class)
@JsonDeserialize(using = IonLocalDateDeserializer.class)
private final LocalDate dob;
private final String govId;
private final String govIdType;
private final String address;
@JsonCreator
public Person(@JsonProperty("FirstName") final String firstName,
@JsonProperty("LastName") final String lastName,
@JsonProperty("DOB") final LocalDate dob,
@JsonProperty("GovId") final String govId,
@JsonProperty("GovIdType") final String govIdType,
@JsonProperty("Address") final String address) {
this.firstName = firstName;
this.lastName = lastName;
this.dob = dob;
this.govId = govId;
this.govIdType = govIdType;
this.address = address;
}
@JsonProperty("Address")
public String getAddress() {
return address;
}
@JsonProperty("DOB")
public LocalDate getDob() {
return dob;
}
@JsonProperty("FirstName")
public String getFirstName() {
return firstName;
}
@JsonProperty("LastName")
public String getLastName() {
return lastName;
}
@JsonProperty("GovId")
public String getGovId() {
return govId;
}
@JsonProperty("GovIdType")
public String getGovIdType() {
return govIdType;
}
/**
* This returns the unique document ID given a specific government ID.
*
* @param txn
* A transaction executor object.
* @param govId
* The government ID of a driver.
* @return the unique document ID.
*/
public static String getDocumentIdByGovId(final TransactionExecutor txn, final String govId) {
return SampleData.getDocumentId(txn, Constants.PERSON_TABLE_NAME, "GovId", govId);
}
@Override
public String toString() {
return "Person{" +
"firstName='" + firstName + '\'' +
", lastName='" + lastName + '\'' +
", dob=" + dob +
", govId='" + govId + '\'' +
", govIdType='" + govIdType + '\'' +
", address='" + address + '\'' +
'}';
}
}
```
1. `VehicleRegistration.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.Constants;
import software.amazon.qldb.tutorial.model.streams.RevisionData;
import java.math.BigDecimal;
import java.time.LocalDate;
/**
* Represents a vehicle registration, serializable to (and from) Ion.
*/
public final class VehicleRegistration implements RevisionData {
private final String vin;
private final String licensePlateNumber;
private final String state;
private final String city;
private final BigDecimal pendingPenaltyTicketAmount;
private final LocalDate validFromDate;
private final LocalDate validToDate;
private final Owners owners;
@JsonCreator
public VehicleRegistration(@JsonProperty("VIN") final String vin,
@JsonProperty("LicensePlateNumber") final String licensePlateNumber,
@JsonProperty("State") final String state,
@JsonProperty("City") final String city,
@JsonProperty("PendingPenaltyTicketAmount") final BigDecimal pendingPenaltyTicketAmount,
@JsonProperty("ValidFromDate") final LocalDate validFromDate,
@JsonProperty("ValidToDate") final LocalDate validToDate,
@JsonProperty("Owners") final Owners owners) {
this.vin = vin;
this.licensePlateNumber = licensePlateNumber;
this.state = state;
this.city = city;
this.pendingPenaltyTicketAmount = pendingPenaltyTicketAmount;
this.validFromDate = validFromDate;
this.validToDate = validToDate;
this.owners = owners;
}
@JsonProperty("City")
public String getCity() {
return city;
}
@JsonProperty("LicensePlateNumber")
public String getLicensePlateNumber() {
return licensePlateNumber;
}
@JsonProperty("Owners")
public Owners getOwners() {
return owners;
}
@JsonProperty("PendingPenaltyTicketAmount")
public BigDecimal getPendingPenaltyTicketAmount() {
return pendingPenaltyTicketAmount;
}
@JsonProperty("State")
public String getState() {
return state;
}
@JsonProperty("ValidFromDate")
@JsonSerialize(using = IonLocalDateSerializer.class)
@JsonDeserialize(using = IonLocalDateDeserializer.class)
public LocalDate getValidFromDate() {
return validFromDate;
}
@JsonProperty("ValidToDate")
@JsonSerialize(using = IonLocalDateSerializer.class)
@JsonDeserialize(using = IonLocalDateDeserializer.class)
public LocalDate getValidToDate() {
return validToDate;
}
@JsonProperty("VIN")
public String getVin() {
return vin;
}
/**
* Returns the unique document ID of a vehicle given a specific VIN.
*
* @param txn
* A transaction executor object.
* @param vin
* The VIN of a vehicle.
* @return the unique document ID of the specified vehicle.
*/
public static String getDocumentIdByVin(final TransactionExecutor txn, final String vin) {
return SampleData.getDocumentId(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, "VIN", vin);
}
@Override
public String toString() {
return "VehicleRegistration{" +
"vin='" + vin + '\'' +
", licensePlateNumber='" + licensePlateNumber + '\'' +
", state='" + state + '\'' +
", city='" + city + '\'' +
", pendingPenaltyTicketAmount=" + pendingPenaltyTicketAmount +
", validFromDate=" + validFromDate +
", validToDate=" + validToDate +
", owners=" + owners +
'}';
}
}
```
1. `Vehicle.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import software.amazon.qldb.tutorial.model.streams.RevisionData;
/**
* Represents a vehicle, serializable to (and from) Ion.
*/
public final class Vehicle implements RevisionData {
private final String vin;
private final String type;
private final int year;
private final String make;
private final String model;
private final String color;
@JsonCreator
public Vehicle(@JsonProperty("VIN") final String vin,
@JsonProperty("Type") final String type,
@JsonProperty("Year") final int year,
@JsonProperty("Make") final String make,
@JsonProperty("Model") final String model,
@JsonProperty("Color") final String color) {
this.vin = vin;
this.type = type;
this.year = year;
this.make = make;
this.model = model;
this.color = color;
}
@JsonProperty("Color")
public String getColor() {
return color;
}
@JsonProperty("Make")
public String getMake() {
return make;
}
@JsonProperty("Model")
public String getModel() {
return model;
}
@JsonProperty("Type")
public String getType() {
return type;
}
@JsonProperty("VIN")
public String getVin() {
return vin;
}
@JsonProperty("Year")
public int getYear() {
return year;
}
@Override
public String toString() {
return "Vehicle{" +
"vin='" + vin + '\'' +
", type='" + type + '\'' +
", year=" + year +
", make='" + make + '\'' +
", model='" + model + '\'' +
", color='" + color + '\'' +
'}';
}
}
```
1. `Owner.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.fasterxml.jackson.annotation.JsonProperty;
/**
* Represents a vehicle owner, serializable to (and from) Ion.
*/
public final class Owner {
private final String personId;
public Owner(@JsonProperty("PersonId") final String personId) {
this.personId = personId;
}
@JsonProperty("PersonId")
public String getPersonId() {
return personId;
}
@Override
public String toString() {
return "Owner{" +
"personId='" + personId + '\'' +
'}';
}
}
```
1. `Owners.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.fasterxml.jackson.annotation.JsonProperty;
import java.util.List;
/**
* Represents a set of owners for a given vehicle, serializable to (and from) Ion.
*/
public final class Owners {
private final Owner primaryOwner;
private final List secondaryOwners;
public Owners(@JsonProperty("PrimaryOwner") final Owner primaryOwner,
@JsonProperty("SecondaryOwners") final List secondaryOwners) {
this.primaryOwner = primaryOwner;
this.secondaryOwners = secondaryOwners;
}
@JsonProperty("PrimaryOwner")
public Owner getPrimaryOwner() {
return primaryOwner;
}
@JsonProperty("SecondaryOwners")
public List getSecondaryOwners() {
return secondaryOwners;
}
@Override
public String toString() {
return "Owners{" +
"primaryOwner=" + primaryOwner +
", secondaryOwners=" + secondaryOwners +
'}';
}
}
```
1. `DmlResultDocument.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
/**
* Contains information about an individual document inserted or modified
* as a result of DML.
*/
public class DmlResultDocument {
private String documentId;
@JsonCreator
public DmlResultDocument(@JsonProperty("documentId") final String documentId) {
this.documentId = documentId;
}
public String getDocumentId() {
return documentId;
}
@Override
public String toString() {
return "DmlResultDocument{"
+ "documentId='" + documentId + '\''
+ '}';
}
}
```
1. `RevisionData.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model.streams;
/**
* Allows modeling the content of all revisions as a generic revision data. Used
* in the {@link Revision} and extended by domain models in {@link
* software.amazon.qldb.tutorial.model} to make it easier to write the {@link
* Revision.RevisionDataDeserializer} that must deserialize the {@link
* Revision#data} from different domain models.
*/
public interface RevisionData { }
```
1. `RevisionMetadata.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.amazon.ion.IonInt;
import com.amazon.ion.IonString;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonTimestamp;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.fasterxml.jackson.dataformat.ion.IonTimestampSerializers;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Date;
import java.util.Objects;
/**
* Represents the metadata field of a QLDB Document
*/
public class RevisionMetadata {
private static final Logger log = LoggerFactory.getLogger(RevisionMetadata.class);
private final String id;
private final long version;
@JsonSerialize(using = IonTimestampSerializers.IonTimestampJavaDateSerializer.class)
private final Date txTime;
private final String txId;
@JsonCreator
public RevisionMetadata(@JsonProperty("id") final String id,
@JsonProperty("version") final long version,
@JsonProperty("txTime") final Date txTime,
@JsonProperty("txId") final String txId) {
this.id = id;
this.version = version;
this.txTime = txTime;
this.txId = txId;
}
/**
* Gets the unique ID of a QLDB document.
*
* @return the document ID.
*/
public String getId() {
return id;
}
/**
* Gets the version number of the document in the document's modification history.
* @return the version number.
*/
public long getVersion() {
return version;
}
/**
* Gets the time during which the document was modified.
*
* @return the transaction time.
*/
public Date getTxTime() {
return txTime;
}
/**
* Gets the transaction ID associated with this document.
*
* @return the transaction ID.
*/
public String getTxId() {
return txId;
}
public static RevisionMetadata fromIon(final IonStruct ionStruct) {
if (ionStruct == null) {
throw new IllegalArgumentException("Metadata cannot be null");
}
try {
IonString id = (IonString) ionStruct.get("id");
IonInt version = (IonInt) ionStruct.get("version");
IonTimestamp txTime = (IonTimestamp) ionStruct.get("txTime");
IonString txId = (IonString) ionStruct.get("txId");
if (id == null || version == null || txTime == null || txId == null) {
throw new IllegalArgumentException("Document is missing required fields");
}
return new RevisionMetadata(id.stringValue(), version.longValue(), new Date(txTime.getMillis()), txId.stringValue());
} catch (ClassCastException e) {
log.error("Failed to parse ion document");
throw new IllegalArgumentException("Document members are not of the correct type", e);
}
}
/**
* Converts a {@link RevisionMetadata} object to a string.
*
* @return the string representation of the {@link QldbRevision} object.
*/
@Override
public String toString() {
return "Metadata{"
+ "id='" + id + '\''
+ ", version=" + version
+ ", txTime=" + txTime
+ ", txId='" + txId
+ '\''
+ '}';
}
/**
* Check whether two {@link RevisionMetadata} objects are equivalent.
*
* @return {@code true} if the two objects are equal, {@code false} otherwise.
*/
@Override
public boolean equals(Object o) {
if (this == o) { return true; }
if (o == null || getClass() != o.getClass()) { return false; }
RevisionMetadata metadata = (RevisionMetadata) o;
return version == metadata.version
&& id.equals(metadata.id)
&& txTime.equals(metadata.txTime)
&& txId.equals(metadata.txId);
}
/**
* Generate a hash code for the {@link RevisionMetadata} object.
*
* @return the hash code.
*/
@Override
public int hashCode() {
// CHECKSTYLE:OFF - Disabling as we are generating a hashCode of multiple properties.
return Objects.hash(id, version, txTime, txId);
// CHECKSTYLE:ON
}
}
```
1. `QldbRevision.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.amazon.ion.IonBlob;
import com.amazon.ion.IonStruct;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.tutorial.Constants;
import software.amazon.qldb.tutorial.Verifier;
import java.io.IOException;
import java.util.Arrays;
import java.util.Objects;
/**
* Represents a QldbRevision including both user data and metadata.
*/
public final class QldbRevision {
private static final Logger log = LoggerFactory.getLogger(QldbRevision.class);
private final BlockAddress blockAddress;
private final RevisionMetadata metadata;
private final byte[] hash;
private final byte[] dataHash;
private final IonStruct data;
@JsonCreator
public QldbRevision(@JsonProperty("blockAddress") final BlockAddress blockAddress,
@JsonProperty("metadata") final RevisionMetadata metadata,
@JsonProperty("hash") final byte[] hash,
@JsonProperty("dataHash") final byte[] dataHash,
@JsonProperty("data") final IonStruct data) {
this.blockAddress = blockAddress;
this.metadata = metadata;
this.hash = hash;
this.dataHash = dataHash;
this.data = data;
}
/**
* Gets the unique ID of a QLDB document.
*
* @return the {@link BlockAddress} object.
*/
public BlockAddress getBlockAddress() {
return blockAddress;
}
/**
* Gets the metadata of the revision.
*
* @return the {@link RevisionMetadata} object.
*/
public RevisionMetadata getMetadata() {
return metadata;
}
/**
* Gets the SHA-256 hash value of the revision.
* This is equivalent to the hash of the revision metadata and data.
*
* @return the byte array representing the hash.
*/
public byte[] getHash() {
return hash;
}
/**
* Gets the SHA-256 hash value of the data portion of the revision.
* This is only present if the revision is redacted.
*
* @return the byte array representing the hash.
*/
public byte[] getDataHash() {
return dataHash;
}
/**
* Gets the revision data.
*
* @return the revision data.
*/
public IonStruct getData() {
return data;
}
/**
* Returns true if the revision has been redacted.
* @return a boolean value representing the redaction status
* of this revision.
*/
public Boolean isRedacted() {
return dataHash != null;
}
/**
* Constructs a new {@link QldbRevision} from an {@link IonStruct}.
*
* The specified {@link IonStruct} must include the following fields
*
* - blockAddress -- a {@link BlockAddress},
* - metadata -- a {@link RevisionMetadata},
* - hash -- the revision's hash calculated by QLDB,
* - dataHash -- the user data's hash calculated by QLDB (only present if revision is redacted),
* - data -- an {@link IonStruct} containing user data in the document.
*
* If any of these fields are missing or are malformed, then throws {@link IllegalArgumentException}.
*
* If the document hash calculated from the members of the specified {@link IonStruct} does not match
* the hash member of the {@link IonStruct} then throws {@link IllegalArgumentException}.
*
* @param ionStruct
* The {@link IonStruct} that contains a {@link QldbRevision} object.
* @return the converted {@link QldbRevision} object.
* @throws IOException if failed to parse parameter {@link IonStruct}.
*/
public static QldbRevision fromIon(final IonStruct ionStruct) throws IOException {
try {
BlockAddress blockAddress = Constants.MAPPER.readValue(ionStruct.get("blockAddress"), BlockAddress.class);
IonBlob revisionHash = (IonBlob) ionStruct.get("hash");
IonStruct metadataStruct = (IonStruct) ionStruct.get("metadata");
IonStruct data = ionStruct.get("data") == null || ionStruct.get("data").isNullValue() ?
null : (IonStruct) ionStruct.get("data");
IonBlob dataHash = ionStruct.get("dataHash") == null || ionStruct.get("dataHash").isNullValue() ?
null : (IonBlob) ionStruct.get("dataHash");
if (revisionHash == null || metadataStruct == null) {
throw new IllegalArgumentException("Document is missing required fields");
}
byte[] dataHashBytes = dataHash != null ? dataHash.getBytes() : QldbIonUtils.hashIonValue(data);
verifyRevisionHash(metadataStruct, dataHashBytes, revisionHash.getBytes());
RevisionMetadata metadata = RevisionMetadata.fromIon(metadataStruct);
return new QldbRevision(
blockAddress,
metadata,
revisionHash.getBytes(),
dataHash != null ? dataHash.getBytes() : null,
data
);
} catch (ClassCastException e) {
log.error("Failed to parse ion document");
throw new IllegalArgumentException("Document members are not of the correct type", e);
}
}
/**
* Converts a {@link QldbRevision} object to string.
*
* @return the string representation of the {@link QldbRevision} object.
*/
@Override
public String toString() {
return "QldbRevision{" +
"blockAddress=" + blockAddress +
", metadata=" + metadata +
", hash=" + Arrays.toString(hash) +
", dataHash=" + Arrays.toString(dataHash) +
", data=" + data +
'}';
}
/**
* Check whether two {@link QldbRevision} objects are equivalent.
*
* @return {@code true} if the two objects are equal, {@code false} otherwise.
*/
@Override
public boolean equals(final Object o) {
if (this == o) {
return true;
}
if (!(o instanceof QldbRevision)) {
return false;
}
final QldbRevision that = (QldbRevision) o;
return Objects.equals(getBlockAddress(), that.getBlockAddress())
&& Objects.equals(getMetadata(), that.getMetadata())
&& Arrays.equals(getHash(), that.getHash())
&& Arrays.equals(getDataHash(), that.getDataHash())
&& Objects.equals(getData(), that.getData());
}
/**
* Create a hash code for the {@link QldbRevision} object.
*
* @return the hash code.
*/
@Override
public int hashCode() {
// CHECKSTYLE:OFF - Disabling as we are generating a hashCode of multiple properties.
int result = Objects.hash(blockAddress, metadata, data);
// CHECKSTYLE:ON
result = 31 * result + Arrays.hashCode(hash);
return result;
}
/**
* Throws an IllegalArgumentException if the hash of the revision data and metadata
* does not match the hash provided by QLDB with the revision.
*/
public void verifyRevisionHash() {
// Certain internal-only system revisions only contain a hash which cannot be
// further computed. However, these system hashes still participate to validate
// the journal block. User revisions will always contain values for all fields
// and can therefore have their hash computed.
if (blockAddress == null && metadata == null && data == null && dataHash == null) {
return;
}
try {
IonStruct metadataIon = (IonStruct) Constants.MAPPER.writeValueAsIonValue(metadata);
byte[] dataHashBytes = isRedacted() ? dataHash : QldbIonUtils.hashIonValue(data);
verifyRevisionHash(metadataIon, dataHashBytes, hash);
} catch (IOException e) {
throw new IllegalArgumentException("Could not encode revision metadata to ion.", e);
}
}
private static void verifyRevisionHash(IonStruct metadata, byte[] dataHash, byte[] expectedHash) {
byte[] metadataHash = QldbIonUtils.hashIonValue(metadata);
byte[] candidateHash = Verifier.dot(metadataHash, dataHash);
if (!Arrays.equals(candidateHash, expectedHash)) {
throw new IllegalArgumentException("Hash entry of QLDB revision and computed hash "
+ "of QLDB revision do not match");
}
}
}
```
1. `IonLocalDateDeserializer.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.amazon.ion.Timestamp;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import java.io.IOException;
import java.time.LocalDate;
/**
* Deserializes [java.time.LocalDate] from Ion.
*/
public class IonLocalDateDeserializer extends JsonDeserializer {
@Override
public LocalDate deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException {
return timestampToLocalDate((Timestamp) jp.getEmbeddedObject());
}
private LocalDate timestampToLocalDate(Timestamp timestamp) {
return LocalDate.of(timestamp.getYear(), timestamp.getMonth(), timestamp.getDay());
}
}
```
1. `IonLocalDateSerializer.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.amazon.ion.Timestamp;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.ser.std.StdScalarSerializer;
import com.fasterxml.jackson.dataformat.ion.IonGenerator;
import java.io.IOException;
import java.time.LocalDate;
/**
* Serializes [java.time.LocalDate] to Ion.
*/
public class IonLocalDateSerializer extends StdScalarSerializer {
public IonLocalDateSerializer() {
super(LocalDate.class);
}
@Override
public void serialize(LocalDate date, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
Timestamp timestamp = Timestamp.forDay(date.getYear(), date.getMonthValue(), date.getDayOfMonth());
((IonGenerator) jsonGenerator).writeValue(timestamp);
}
}
```
1. 次のファイル (`SampleData.java`) を確認します。このファイルには、`vehicle-registration` テーブルに挿入するサンプルデータが含まれています。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.amazon.ion.IonString;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonValue;
import java.io.IOException;
import java.math.BigDecimal;
import java.text.ParseException;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.ConnectToLedger;
import software.amazon.qldb.tutorial.Constants;
import software.amazon.qldb.tutorial.qldb.DmlResultDocument;
import software.amazon.qldb.tutorial.qldb.QldbRevision;
/**
* Sample domain objects for use throughout this tutorial.
*/
public final class SampleData {
public static final DateTimeFormatter DATE_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd");
public static final List REGISTRATIONS = Collections.unmodifiableList(Arrays.asList(
new VehicleRegistration("1N4AL11D75C109151", "LEWISR261LL", "WA", "Seattle",
BigDecimal.valueOf(90.25), convertToLocalDate("2017-08-21"), convertToLocalDate("2020-05-11"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("KM8SRDHF6EU074761", "CA762X", "WA", "Kent",
BigDecimal.valueOf(130.75), convertToLocalDate("2017-09-14"), convertToLocalDate("2020-06-25"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("3HGGK5G53FM761765", "CD820Z", "WA", "Everett",
BigDecimal.valueOf(442.30), convertToLocalDate("2011-03-17"), convertToLocalDate("2021-03-24"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("1HVBBAANXWH544237", "LS477D", "WA", "Tacoma",
BigDecimal.valueOf(42.20), convertToLocalDate("2011-10-26"), convertToLocalDate("2023-09-25"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("1C4RJFAG0FC625797", "TH393F", "WA", "Olympia",
BigDecimal.valueOf(30.45), convertToLocalDate("2013-09-02"), convertToLocalDate("2024-03-19"),
new Owners(new Owner(null), Collections.emptyList()))
));
public static final List VEHICLES = Collections.unmodifiableList(Arrays.asList(
new Vehicle("1N4AL11D75C109151", "Sedan", 2011, "Audi", "A5", "Silver"),
new Vehicle("KM8SRDHF6EU074761", "Sedan", 2015, "Tesla", "Model S", "Blue"),
new Vehicle("3HGGK5G53FM761765", "Motorcycle", 2011, "Ducati", "Monster 1200", "Yellow"),
new Vehicle("1HVBBAANXWH544237", "Semi", 2009, "Ford", "F 150", "Black"),
new Vehicle("1C4RJFAG0FC625797", "Sedan", 2019, "Mercedes", "CLK 350", "White")
));
public static final List PEOPLE = Collections.unmodifiableList(Arrays.asList(
new Person("Raul", "Lewis", convertToLocalDate("1963-08-19"),
"LEWISR261LL", "Driver License", "1719 University Street, Seattle, WA, 98109"),
new Person("Brent", "Logan", convertToLocalDate("1967-07-03"),
"LOGANB486CG", "Driver License", "43 Stockert Hollow Road, Everett, WA, 98203"),
new Person("Alexis", "Pena", convertToLocalDate("1974-02-10"),
"744 849 301", "SSN", "4058 Melrose Street, Spokane Valley, WA, 99206"),
new Person("Melvin", "Parker", convertToLocalDate("1976-05-22"),
"P626-168-229-765", "Passport", "4362 Ryder Avenue, Seattle, WA, 98101"),
new Person("Salvatore", "Spencer", convertToLocalDate("1997-11-15"),
"S152-780-97-415-0", "Passport", "4450 Honeysuckle Lane, Seattle, WA, 98101")
));
public static final List LICENSES = Collections.unmodifiableList(Arrays.asList(
new DriversLicense(null, "LEWISR261LL", "Learner",
convertToLocalDate("2016-12-20"), convertToLocalDate("2020-11-15")),
new DriversLicense(null, "LOGANB486CG", "Probationary",
convertToLocalDate("2016-04-06"), convertToLocalDate("2020-11-15")),
new DriversLicense(null, "744 849 301", "Full",
convertToLocalDate("2017-12-06"), convertToLocalDate("2022-10-15")),
new DriversLicense(null, "P626-168-229-765", "Learner",
convertToLocalDate("2017-08-16"), convertToLocalDate("2021-11-15")),
new DriversLicense(null, "S152-780-97-415-0", "Probationary",
convertToLocalDate("2015-08-15"), convertToLocalDate("2021-08-21"))
));
private SampleData() { }
/**
* Converts a date string with the format 'yyyy-MM-dd' into a {@link java.util.Date} object.
*
* @param date
* The date string to convert.
* @return {@link java.time.LocalDate} or null if there is a {@link ParseException}
*/
public static synchronized LocalDate convertToLocalDate(String date) {
return LocalDate.parse(date, DATE_TIME_FORMAT);
}
/**
* Convert the result set into a list of IonValues.
*
* @param result
* The result set to convert.
* @return a list of IonValues.
*/
public static List toIonValues(Result result) {
final List valueList = new ArrayList<>();
result.iterator().forEachRemaining(valueList::add);
return valueList;
}
/**
* Get the document ID of a particular document.
*
* @param txn
* A transaction executor object.
* @param tableName
* Name of the table containing the document.
* @param identifier
* The identifier used to narrow down the search.
* @param value
* Value of the identifier.
* @return the list of document IDs in the result set.
*/
public static String getDocumentId(final TransactionExecutor txn, final String tableName,
final String identifier, final String value) {
try {
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(value));
final String query = String.format("SELECT metadata.id FROM _ql_committed_%s AS p WHERE p.data.%s = ?",
tableName, identifier);
Result result = txn.execute(query, parameters);
if (result.isEmpty()) {
throw new IllegalStateException("Unable to retrieve document ID using " + value);
}
return getStringValueOfStructField((IonStruct) result.iterator().next(), "id");
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Get the document by ID.
*
* @param tableName
* Name of the table to insert documents into.
* @param documentId
* The unique ID of a document in the Person table.
* @return a {@link QldbRevision} object.
* @throws IllegalStateException if failed to convert parameter into {@link IonValue}.
*/
public static QldbRevision getDocumentById(String tableName, String documentId) {
try {
final IonValue ionValue = Constants.MAPPER.writeValueAsIonValue(documentId);
Result result = ConnectToLedger.getDriver().execute(txn -> {
return txn.execute("SELECT c.* FROM _ql_committed_" + tableName + " AS c BY docId "
+ "WHERE docId = ?", ionValue);
});
if (result.isEmpty()) {
throw new IllegalStateException("Unable to retrieve document by id " + documentId + " in table " + tableName);
}
return Constants.MAPPER.readValue(result.iterator().next(), QldbRevision.class);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Return a list of modified document IDs as strings from a DML {@link Result}.
*
* @param result
* The result set from a DML operation.
* @return the list of document IDs modified by the operation.
*/
public static List getDocumentIdsFromDmlResult(final Result result) {
final List strings = new ArrayList<>();
result.iterator().forEachRemaining(row -> strings.add(getDocumentIdFromDmlResultDocument(row)));
return strings;
}
/**
* Convert the given DML result row's document ID to string.
*
* @param dmlResultDocument
* The {@link IonValue} representing the results of a DML operation.
* @return a string of document ID.
*/
public static String getDocumentIdFromDmlResultDocument(final IonValue dmlResultDocument) {
try {
DmlResultDocument result = Constants.MAPPER.readValue(dmlResultDocument, DmlResultDocument.class);
return result.getDocumentId();
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Get the String value of a given {@link IonStruct} field name.
* @param struct the {@link IonStruct} from which to get the value.
* @param fieldName the name of the field from which to get the value.
* @return the String value of the field within the given {@link IonStruct}.
*/
public static String getStringValueOfStructField(final IonStruct struct, final String fieldName) {
return ((IonString) struct.get(fieldName)).stringValue();
}
/**
* Return a copy of the given driver's license with updated person Id.
*
* @param oldLicense
* The old driver's license to update.
* @param personId
* The PersonId of the driver.
* @return the updated {@link DriversLicense}.
*/
public static DriversLicense updatePersonIdDriversLicense(final DriversLicense oldLicense, final String personId) {
return new DriversLicense(personId, oldLicense.getLicenseNumber(), oldLicense.getLicenseType(),
oldLicense.getValidFromDate(), oldLicense.getValidToDate());
}
/**
* Return a copy of the given vehicle registration with updated person Id.
*
* @param oldRegistration
* The old vehicle registration to update.
* @param personId
* The PersonId of the driver.
* @return the updated {@link VehicleRegistration}.
*/
public static VehicleRegistration updateOwnerVehicleRegistration(final VehicleRegistration oldRegistration,
final String personId) {
return new VehicleRegistration(oldRegistration.getVin(), oldRegistration.getLicensePlateNumber(),
oldRegistration.getState(), oldRegistration.getCity(), oldRegistration.getPendingPenaltyTicketAmount(),
oldRegistration.getValidFromDate(), oldRegistration.getValidToDate(),
new Owners(new Owner(personId), Collections.emptyList()));
}
}
```
------
#### [ 1.x ]
**重要**
Amazon Ion パッケージの場合、アプリケーションで名前空間 `com.amazon.ion` を使用する必要があります。 AWS SDK for Java は、名前空間 の別の Ion パッケージに依存しますが`software.amazon.ion`、これは QLDB ドライバーと互換性のないレガシーパッケージです。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.model;
import com.amazon.ion.IonString;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonValue;
import software.amazon.qldb.QldbSession;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.Constants;
import software.amazon.qldb.tutorial.qldb.DmlResultDocument;
import software.amazon.qldb.tutorial.qldb.QldbRevision;
import java.io.IOException;
import java.math.BigDecimal;
import java.text.ParseException;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
/**
* Sample domain objects for use throughout this tutorial.
*/
public final class SampleData {
public static final DateTimeFormatter DATE_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd");
public static final List REGISTRATIONS = Collections.unmodifiableList(Arrays.asList(
new VehicleRegistration("1N4AL11D75C109151", "LEWISR261LL", "WA", "Seattle",
BigDecimal.valueOf(90.25), convertToLocalDate("2017-08-21"), convertToLocalDate("2020-05-11"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("KM8SRDHF6EU074761", "CA762X", "WA", "Kent",
BigDecimal.valueOf(130.75), convertToLocalDate("2017-09-14"), convertToLocalDate("2020-06-25"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("3HGGK5G53FM761765", "CD820Z", "WA", "Everett",
BigDecimal.valueOf(442.30), convertToLocalDate("2011-03-17"), convertToLocalDate("2021-03-24"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("1HVBBAANXWH544237", "LS477D", "WA", "Tacoma",
BigDecimal.valueOf(42.20), convertToLocalDate("2011-10-26"), convertToLocalDate("2023-09-25"),
new Owners(new Owner(null), Collections.emptyList())),
new VehicleRegistration("1C4RJFAG0FC625797", "TH393F", "WA", "Olympia",
BigDecimal.valueOf(30.45), convertToLocalDate("2013-09-02"), convertToLocalDate("2024-03-19"),
new Owners(new Owner(null), Collections.emptyList()))
));
public static final List VEHICLES = Collections.unmodifiableList(Arrays.asList(
new Vehicle("1N4AL11D75C109151", "Sedan", 2011, "Audi", "A5", "Silver"),
new Vehicle("KM8SRDHF6EU074761", "Sedan", 2015, "Tesla", "Model S", "Blue"),
new Vehicle("3HGGK5G53FM761765", "Motorcycle", 2011, "Ducati", "Monster 1200", "Yellow"),
new Vehicle("1HVBBAANXWH544237", "Semi", 2009, "Ford", "F 150", "Black"),
new Vehicle("1C4RJFAG0FC625797", "Sedan", 2019, "Mercedes", "CLK 350", "White")
));
public static final List PEOPLE = Collections.unmodifiableList(Arrays.asList(
new Person("Raul", "Lewis", convertToLocalDate("1963-08-19"),
"LEWISR261LL", "Driver License", "1719 University Street, Seattle, WA, 98109"),
new Person("Brent", "Logan", convertToLocalDate("1967-07-03"),
"LOGANB486CG", "Driver License", "43 Stockert Hollow Road, Everett, WA, 98203"),
new Person("Alexis", "Pena", convertToLocalDate("1974-02-10"),
"744 849 301", "SSN", "4058 Melrose Street, Spokane Valley, WA, 99206"),
new Person("Melvin", "Parker", convertToLocalDate("1976-05-22"),
"P626-168-229-765", "Passport", "4362 Ryder Avenue, Seattle, WA, 98101"),
new Person("Salvatore", "Spencer", convertToLocalDate("1997-11-15"),
"S152-780-97-415-0", "Passport", "4450 Honeysuckle Lane, Seattle, WA, 98101")
));
public static final List LICENSES = Collections.unmodifiableList(Arrays.asList(
new DriversLicense(null, "LEWISR261LL", "Learner",
convertToLocalDate("2016-12-20"), convertToLocalDate("2020-11-15")),
new DriversLicense(null, "LOGANB486CG", "Probationary",
convertToLocalDate("2016-04-06"), convertToLocalDate("2020-11-15")),
new DriversLicense(null, "744 849 301", "Full",
convertToLocalDate("2017-12-06"), convertToLocalDate("2022-10-15")),
new DriversLicense(null, "P626-168-229-765", "Learner",
convertToLocalDate("2017-08-16"), convertToLocalDate("2021-11-15")),
new DriversLicense(null, "S152-780-97-415-0", "Probationary",
convertToLocalDate("2015-08-15"), convertToLocalDate("2021-08-21"))
));
private SampleData() { }
/**
* Converts a date string with the format 'yyyy-MM-dd' into a {@link java.util.Date} object.
*
* @param date
* The date string to convert.
* @return {@link LocalDate} or null if there is a {@link ParseException}
*/
public static synchronized LocalDate convertToLocalDate(String date) {
return LocalDate.parse(date, DATE_TIME_FORMAT);
}
/**
* Convert the result set into a list of IonValues.
*
* @param result
* The result set to convert.
* @return a list of IonValues.
*/
public static List toIonValues(Result result) {
final List valueList = new ArrayList<>();
result.iterator().forEachRemaining(valueList::add);
return valueList;
}
/**
* Get the document ID of a particular document.
*
* @param txn
* A transaction executor object.
* @param tableName
* Name of the table containing the document.
* @param identifier
* The identifier used to narrow down the search.
* @param value
* Value of the identifier.
* @return the list of document IDs in the result set.
*/
public static String getDocumentId(final TransactionExecutor txn, final String tableName,
final String identifier, final String value) {
try {
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(value));
final String query = String.format("SELECT metadata.id FROM _ql_committed_%s AS p WHERE p.data.%s = ?",
tableName, identifier);
Result result = txn.execute(query, parameters);
if (result.isEmpty()) {
throw new IllegalStateException("Unable to retrieve document ID using " + value);
}
return getStringValueOfStructField((IonStruct) result.iterator().next(), "id");
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Get the document by ID.
*
* @param qldbSession
* A QLDB session.
* @param tableName
* Name of the table to insert documents into.
* @param documentId
* The unique ID of a document in the Person table.
* @return a {@link QldbRevision} object.
* @throws IllegalStateException if failed to convert parameter into {@link IonValue}.
*/
public static QldbRevision getDocumentById(QldbSession qldbSession, String tableName, String documentId) {
try {
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(documentId));
final String query = String.format("SELECT c.* FROM _ql_committed_%s AS c BY docId WHERE docId = ?", tableName);
Result result = qldbSession.execute(query, parameters);
if (result.isEmpty()) {
throw new IllegalStateException("Unable to retrieve document by id " + documentId + " in table " + tableName);
}
return Constants.MAPPER.readValue(result.iterator().next(), QldbRevision.class);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Return a list of modified document IDs as strings from a DML {@link Result}.
*
* @param result
* The result set from a DML operation.
* @return the list of document IDs modified by the operation.
*/
public static List getDocumentIdsFromDmlResult(final Result result) {
final List strings = new ArrayList<>();
result.iterator().forEachRemaining(row -> strings.add(getDocumentIdFromDmlResultDocument(row)));
return strings;
}
/**
* Convert the given DML result row's document ID to string.
*
* @param dmlResultDocument
* The {@link IonValue} representing the results of a DML operation.
* @return a string of document ID.
*/
public static String getDocumentIdFromDmlResultDocument(final IonValue dmlResultDocument) {
try {
DmlResultDocument result = Constants.MAPPER.readValue(dmlResultDocument, DmlResultDocument.class);
return result.getDocumentId();
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Get the String value of a given {@link IonStruct} field name.
* @param struct the {@link IonStruct} from which to get the value.
* @param fieldName the name of the field from which to get the value.
* @return the String value of the field within the given {@link IonStruct}.
*/
public static String getStringValueOfStructField(final IonStruct struct, final String fieldName) {
return ((IonString) struct.get(fieldName)).stringValue();
}
/**
* Return a copy of the given driver's license with updated person Id.
*
* @param oldLicense
* The old driver's license to update.
* @param personId
* The PersonId of the driver.
* @return the updated {@link DriversLicense}.
*/
public static DriversLicense updatePersonIdDriversLicense(final DriversLicense oldLicense, final String personId) {
return new DriversLicense(personId, oldLicense.getLicenseNumber(), oldLicense.getLicenseType(),
oldLicense.getValidFromDate(), oldLicense.getValidToDate());
}
/**
* Return a copy of the given vehicle registration with updated person Id.
*
* @param oldRegistration
* The old vehicle registration to update.
* @param personId
* The PersonId of the driver.
* @return the updated {@link VehicleRegistration}.
*/
public static VehicleRegistration updateOwnerVehicleRegistration(final VehicleRegistration oldRegistration,
final String personId) {
return new VehicleRegistration(oldRegistration.getVin(), oldRegistration.getLicensePlateNumber(),
oldRegistration.getState(), oldRegistration.getCity(), oldRegistration.getPendingPenaltyTicketAmount(),
oldRegistration.getValidFromDate(), oldRegistration.getValidToDate(),
new Owners(new Owner(personId), Collections.emptyList()));
}
}
```
------
**注記**
このクラスは Ion ライブラリを使用して、データを Ion 形式との間で変換するヘルパーメソッドを提供します。
`getDocumentId` メソッドは、プレフィックス `_ql_committed_` を持つテーブルに対してクエリを実行します。これは、テーブルの*コミット済みビュー*にクエリを実行することを示す予約済みプレフィックスです。このビューでは、データは `data` フィールドにネストされており、メタデータは `metadata` フィールドにネストされています。
1. 次のプログラム (`CreateTable.java`) をコンパイルして実行し、前述のテーブルを作成します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Create tables in a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class CreateTable {
public static final Logger log = LoggerFactory.getLogger(CreateTable.class);
private CreateTable() { }
/**
* Registrations, vehicles, owners, and licenses tables being created in a single transaction.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param tableName
* Name of the table to be created.
* @return the number of tables created.
*/
public static int createTable(final TransactionExecutor txn, final String tableName) {
log.info("Creating the '{}' table...", tableName);
final String createTable = String.format("CREATE TABLE %s", tableName);
final Result result = txn.execute(createTable);
log.info("{} table created successfully.", tableName);
return SampleData.toIonValues(result).size();
}
public static void main(final String... args) {
ConnectToLedger.getDriver().execute(txn -> {
createTable(txn, Constants.DRIVERS_LICENSE_TABLE_NAME);
createTable(txn, Constants.PERSON_TABLE_NAME);
createTable(txn, Constants.VEHICLE_TABLE_NAME);
createTable(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME);
});
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Create tables in a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class CreateTable {
public static final Logger log = LoggerFactory.getLogger(CreateTable.class);
private CreateTable() { }
/**
* Registrations, vehicles, owners, and licenses tables being created in a single transaction.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param tableName
* Name of the table to be created.
* @return the number of tables created.
*/
public static int createTable(final TransactionExecutor txn, final String tableName) {
log.info("Creating the '{}' table...", tableName);
final String createTable = String.format("CREATE TABLE %s", tableName);
final Result result = txn.execute(createTable);
log.info("{} table created successfully.", tableName);
return SampleData.toIonValues(result).size();
}
public static void main(final String... args) {
ConnectToLedger.getDriver().execute(txn -> {
createTable(txn, Constants.DRIVERS_LICENSE_TABLE_NAME);
createTable(txn, Constants.PERSON_TABLE_NAME);
createTable(txn, Constants.VEHICLE_TABLE_NAME);
createTable(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME);
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
}
}
```
------
**注記**
このプログラムは、`TransactionExecutor` Lambda を `execute` メソッドに渡す方法を示します。この例では、Lambda 式を使用して 1 つのトランザクションで複数の `CREATE TABLE` PartiQL ステートメントを実行します。
この `execute` メソッドは、暗黙的にトランザクションを開始し、Lambda ですべてのステートメントを実行して、トランザクションを自動コミットします。
1. 前述のように、次のプログラム (`CreateIndex.java`) をコンパイルし実行して、テーブルにインデックスを作成します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Create indexes on tables in a particular ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class CreateIndex {
public static final Logger log = LoggerFactory.getLogger(CreateIndex.class);
private CreateIndex() { }
/**
* In this example, create indexes for registrations and vehicles tables.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param tableName
* Name of the table to be created.
* @param indexAttribute
* The index attribute to use.
* @return the number of tables created.
*/
public static int createIndex(final TransactionExecutor txn, final String tableName, final String indexAttribute) {
log.info("Creating an index on {}...", indexAttribute);
final String createIndex = String.format("CREATE INDEX ON %s (%s)", tableName, indexAttribute);
final Result r = txn.execute(createIndex);
return SampleData.toIonValues(r).size();
}
public static void main(final String... args) {
ConnectToLedger.getDriver().execute(txn -> {
createIndex(txn, Constants.PERSON_TABLE_NAME, Constants.PERSON_GOV_ID_INDEX_NAME);
createIndex(txn, Constants.VEHICLE_TABLE_NAME, Constants.VIN_INDEX_NAME);
createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_NUMBER_INDEX_NAME);
createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_PERSONID_INDEX_NAME);
createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Constants.VIN_INDEX_NAME);
createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME,
Constants.VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME);
});
log.info("Indexes created successfully!");
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Create indexes on tables in a particular ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class CreateIndex {
public static final Logger log = LoggerFactory.getLogger(CreateIndex.class);
private CreateIndex() { }
/**
* In this example, create indexes for registrations and vehicles tables.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param tableName
* Name of the table to be created.
* @param indexAttribute
* The index attribute to use.
* @return the number of tables created.
*/
public static int createIndex(final TransactionExecutor txn, final String tableName, final String indexAttribute) {
log.info("Creating an index on {}...", indexAttribute);
final String createIndex = String.format("CREATE INDEX ON %s (%s)", tableName, indexAttribute);
final Result r = txn.execute(createIndex);
return SampleData.toIonValues(r).size();
}
public static void main(final String... args) {
ConnectToLedger.getDriver().execute(txn -> {
createIndex(txn, Constants.PERSON_TABLE_NAME, Constants.PERSON_GOV_ID_INDEX_NAME);
createIndex(txn, Constants.VEHICLE_TABLE_NAME, Constants.VIN_INDEX_NAME);
createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_NUMBER_INDEX_NAME);
createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_PERSONID_INDEX_NAME);
createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Constants.VIN_INDEX_NAME);
createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME,
Constants.VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME);
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
log.info("Indexes created successfully!");
}
}
```
------
1. 次のプログラム (`InsertDocument.java`) をコンパイルし実行して、サンプルデータをテーブルに挿入します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazon.ion.IonValue;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.DriversLicense;
import software.amazon.qldb.tutorial.model.SampleData;
import software.amazon.qldb.tutorial.model.VehicleRegistration;
/**
* Insert documents into a table in a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class InsertDocument {
public static final Logger log = LoggerFactory.getLogger(InsertDocument.class);
private InsertDocument() { }
/**
* Insert the given list of documents into the specified table and return the document IDs of the inserted documents.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param tableName
* Name of the table to insert documents into.
* @param documents
* List of documents to insert into the specified table.
* @return a list of document IDs.
* @throws IllegalStateException if failed to convert documents into an {@link IonValue}.
*/
public static List insertDocuments(final TransactionExecutor txn, final String tableName,
final List documents) {
log.info("Inserting some documents in the {} table...", tableName);
try {
final String query = String.format("INSERT INTO %s ?", tableName);
final IonValue ionDocuments = Constants.MAPPER.writeValueAsIonValue(documents);
return SampleData.getDocumentIdsFromDmlResult(txn.execute(query, ionDocuments));
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Update PersonIds in driver's licenses and in vehicle registrations using document IDs.
*
* @param documentIds
* List of document IDs representing the PersonIds in DriversLicense and PrimaryOwners in VehicleRegistration.
* @param licenses
* List of driver's licenses to update.
* @param registrations
* List of registrations to update.
*/
public static void updatePersonId(final List documentIds, final List licenses,
final List registrations) {
for (int i = 0; i < documentIds.size(); ++i) {
DriversLicense license = SampleData.LICENSES.get(i);
VehicleRegistration registration = SampleData.REGISTRATIONS.get(i);
licenses.add(SampleData.updatePersonIdDriversLicense(license, documentIds.get(i)));
registrations.add(SampleData.updateOwnerVehicleRegistration(registration, documentIds.get(i)));
}
}
public static void main(final String... args) {
final List newDriversLicenses = new ArrayList<>();
final List newVehicleRegistrations = new ArrayList<>();
ConnectToLedger.getDriver().execute(txn -> {
List documentIds = insertDocuments(txn, Constants.PERSON_TABLE_NAME, SampleData.PEOPLE);
updatePersonId(documentIds, newDriversLicenses, newVehicleRegistrations);
insertDocuments(txn, Constants.VEHICLE_TABLE_NAME, SampleData.VEHICLES);
insertDocuments(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME,
Collections.unmodifiableList(newVehicleRegistrations));
insertDocuments(txn, Constants.DRIVERS_LICENSE_TABLE_NAME,
Collections.unmodifiableList(newDriversLicenses));
});
log.info("Documents inserted successfully!");
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonValue;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.QldbSession;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.DriversLicense;
import software.amazon.qldb.tutorial.model.SampleData;
import software.amazon.qldb.tutorial.model.VehicleRegistration;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* Insert documents into a table in a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class InsertDocument {
public static final Logger log = LoggerFactory.getLogger(InsertDocument.class);
private InsertDocument() { }
/**
* Insert the given list of documents into the specified table and return the document IDs of the inserted documents.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param tableName
* Name of the table to insert documents into.
* @param documents
* List of documents to insert into the specified table.
* @return a list of document IDs.
* @throws IllegalStateException if failed to convert documents into an {@link IonValue}.
*/
public static List insertDocuments(final TransactionExecutor txn, final String tableName,
final List documents) {
log.info("Inserting some documents in the {} table...", tableName);
try {
final String statement = String.format("INSERT INTO %s ?", tableName);
final IonValue ionDocuments = Constants.MAPPER.writeValueAsIonValue(documents);
final List parameters = Collections.singletonList(ionDocuments);
return SampleData.getDocumentIdsFromDmlResult(txn.execute(statement, parameters));
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Update PersonIds in driver's licenses and in vehicle registrations using document IDs.
*
* @param documentIds
* List of document IDs representing the PersonIds in DriversLicense and PrimaryOwners in VehicleRegistration.
* @param licenses
* List of driver's licenses to update.
* @param registrations
* List of registrations to update.
*/
public static void updatePersonId(final List documentIds, final List licenses,
final List registrations) {
for (int i = 0; i < documentIds.size(); ++i) {
DriversLicense license = SampleData.LICENSES.get(i);
VehicleRegistration registration = SampleData.REGISTRATIONS.get(i);
licenses.add(SampleData.updatePersonIdDriversLicense(license, documentIds.get(i)));
registrations.add(SampleData.updateOwnerVehicleRegistration(registration, documentIds.get(i)));
}
}
public static void main(final String... args) {
final List newDriversLicenses = new ArrayList<>();
final List newVehicleRegistrations = new ArrayList<>();
ConnectToLedger.getDriver().execute(txn -> {
List documentIds = insertDocuments(txn, Constants.PERSON_TABLE_NAME, SampleData.PEOPLE);
updatePersonId(documentIds, newDriversLicenses, newVehicleRegistrations);
insertDocuments(txn, Constants.VEHICLE_TABLE_NAME, SampleData.VEHICLES);
insertDocuments(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME,
Collections.unmodifiableList(newVehicleRegistrations));
insertDocuments(txn, Constants.DRIVERS_LICENSE_TABLE_NAME,
Collections.unmodifiableList(newDriversLicenses));
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
log.info("Documents inserted successfully!");
}
}
```
------
**注記**
このプログラムは、パラメータ化された値を渡して `execute` メソッドを呼び出す方法を示します。実行する PartiQL ステートメントに加えて、`IonValue` 型のデータパラメータを渡すことができます。ステートメント文字列の変数プレースホルダーとして疑問符 (`?`) を使用します。
`INSERT` ステートメントが成功すると、 挿入された各ドキュメントの `id` が返されます。
次に、`SELECT` ステートメントを使用すると、`vehicle-registration` 台帳のテーブルからデータを読み取ることができます。[ステップ 4: 台帳のテーブルにクエリを実行する](getting-started.java.step-4.md) に進みます。
# ステップ 4: 台帳のテーブルにクエリを実行する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
Amazon QLDB 台帳にテーブルを作成し、データをロードした後は、クエリを実行して、挿入した車両登録データを確認できます。QLDB は [PartiQL](ql-reference.md) をクエリ言語として使用し、[Amazon Ion](ion.md) をドキュメント指向のデータモデルとして使用します。
PartiQL は、Ion で動作するように拡張されたオープンソースの SQL 互換のクエリ言語です。PartiQL を使用すると、使い慣れた SQL 演算子を使用してデータを挿入、クエリ、および管理できます。Amazon Ion は JSON のスーパーセットです。Ion はオープンソースのドキュメントベースのデータ形式であり、構造化データ、半構造化データ、およびネストされたデータを柔軟に保存および処理できます。
このステップでは、`SELECT` ステートメントを使用して、`vehicle-registration` 台帳のテーブルからデータを読み取ります。
**警告**
インデックス付きルックアップなしで QLDB でクエリを実行すると、完全なテーブルスキャンが呼び出されます。PartiQL は SQL 互換であるため、このようなクエリをサポートしています。ただし、QLDB の本番環境のユースケースではテーブルスキャンを実行しないでください。テーブルスキャンより、同時実行の競合やトランザクションのタイムアウトなど、大きなテーブルでパフォーマンスの問題が発生する可能性があります。
テーブルスキャンを回避するには、インデックス付きフィールドまたはドキュメント ID で**等価演算子を使用する `WHERE` 述語句でステートメントを実行する必要があります (例: `WHERE indexedField = 123` または `WHERE indexedField IN (456, 789)`)。詳細については、「[クエリパフォーマンスの最適化](working.optimize.md)」を参照してください。
**テーブルのクエリを実行するには**
+ 次のプログラム (`FindVehicles.java`) をコンパイルし実行して、台帳の人物に登録されているすべての車両のクエリを実行します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.io.IOException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazon.ion.IonValue;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.Person;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Find all vehicles registered under a person.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class FindVehicles {
public static final Logger log = LoggerFactory.getLogger(FindVehicles.class);
private FindVehicles() { }
/**
* Find vehicles registered under a driver using their government ID.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param govId
* The government ID of the owner.
* @throws IllegalStateException if failed to convert parameters into {@link IonValue}.
*/
public static void findVehiclesForOwner(final TransactionExecutor txn, final String govId) {
try {
final String documentId = Person.getDocumentIdByGovId(txn, govId);
final String query = "SELECT v FROM Vehicle AS v INNER JOIN VehicleRegistration AS r "
+ "ON v.VIN = r.VIN WHERE r.Owners.PrimaryOwner.PersonId = ?";
final Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId));
log.info("List of Vehicles for owner with GovId: {}...", govId);
ScanTable.printDocuments(result);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final Person person = SampleData.PEOPLE.get(0);
ConnectToLedger.getDriver().execute(txn -> {
findVehiclesForOwner(txn, person.getGovId());
});
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.io.IOException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazon.ion.IonValue;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.Person;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Find all vehicles registered under a person.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class FindVehicles {
public static final Logger log = LoggerFactory.getLogger(FindVehicles.class);
private FindVehicles() { }
/**
* Find vehicles registered under a driver using their government ID.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param govId
* The government ID of the owner.
* @throws IllegalStateException if failed to convert parameters into {@link IonValue}.
*/
public static void findVehiclesForOwner(final TransactionExecutor txn, final String govId) {
try {
final String documentId = Person.getDocumentIdByGovId(txn, govId);
final String query = "SELECT v FROM Vehicle AS v INNER JOIN VehicleRegistration AS r "
+ "ON v.VIN = r.VIN WHERE r.Owners.PrimaryOwner.PersonId = ?";
final Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId));
log.info("List of Vehicles for owner with GovId: {}...", govId);
ScanTable.printDocuments(result);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final Person person = SampleData.PEOPLE.get(0);
ConnectToLedger.getDriver().execute(txn -> {
findVehiclesForOwner(txn, person.getGovId());
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
}
}
```
------
**注記**
まず、このプログラムでは、`GovId LEWISR261LL` を使用してドキュメントの `Person` テーブルに対してクエリを実行し、`id` メタデータフィールドを取得します。
次に、このドキュメント `id` を外部キーとして使用して、`PrimaryOwner.PersonId` によって `VehicleRegistration` テーブルをクエリします。また、`VehicleRegistration` が `VIN` フィールドの `Vehicle` テーブルと結合されます。
`vehicle-registration` 台帳のテーブルのドキュメントの変更方法については、「[ステップ 5: 台帳内のドキュメントを変更する](getting-started.java.step-5.md)」を参照してください。
# ステップ 5: 台帳内のドキュメントを変更する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
操作するデータを用意できたところで、Amazon QLDB で `vehicle-registration` 台帳のドキュメントに変更を加えることができます。このステップでは、次のコード例により、データ操作言語 (DML) ステートメントを実行する方法を示します。これらのステートメントは、ある車両の主所有者を更新し、別の車両に第二所有者を追加します。
**ドキュメントに変更を加えるには**
1. 次のプログラム (`TransferVehicleOwnership.java`) をコンパイルおよび実行して、台帳で VIN が `1N4AL11D75C109151` の車両の主所有者を更新します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonReader;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonValue;
import com.amazon.ion.system.IonReaderBuilder;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.Owner;
import software.amazon.qldb.tutorial.model.Person;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Find primary owner for a particular vehicle's VIN.
* Transfer to another primary owner for a particular vehicle's VIN.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class TransferVehicleOwnership {
public static final Logger log = LoggerFactory.getLogger(TransferVehicleOwnership.class);
private TransferVehicleOwnership() { }
/**
* Query a driver's information using the given ID.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param documentId
* The unique ID of a document in the Person table.
* @return a {@link Person} object.
* @throws IllegalStateException if failed to convert parameter into {@link IonValue}.
*/
public static Person findPersonFromDocumentId(final TransactionExecutor txn, final String documentId) {
try {
log.info("Finding person for documentId: {}...", documentId);
final String query = "SELECT p.* FROM Person AS p BY pid WHERE pid = ?";
Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId));
if (result.isEmpty()) {
throw new IllegalStateException("Unable to find person with ID: " + documentId);
}
return Constants.MAPPER.readValue(result.iterator().next(), Person.class);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Find the primary owner for the given VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @return a {@link Person} object.
* @throws IllegalStateException if failed to convert parameter into {@link IonValue}.
*/
public static Person findPrimaryOwnerForVehicle(final TransactionExecutor txn, final String vin) {
try {
log.info("Finding primary owner for vehicle with Vin: {}...", vin);
final String query = "SELECT Owners.PrimaryOwner.PersonId FROM VehicleRegistration AS v WHERE v.VIN = ?";
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin));
Result result = txn.execute(query, parameters);
final List documents = ScanTable.toIonStructs(result);
ScanTable.printDocuments(documents);
if (documents.isEmpty()) {
throw new IllegalStateException("Unable to find registrations with VIN: " + vin);
}
final IonReader reader = IonReaderBuilder.standard().build(documents.get(0));
final String personId = Constants.MAPPER.readValue(reader, LinkedHashMap.class).get("PersonId").toString();
return findPersonFromDocumentId(txn, personId);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Update the primary owner for a vehicle registration with the given documentId.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @param documentId
* New PersonId for the primary owner.
* @throws IllegalStateException if no vehicle registration was found using the given document ID and VIN, or if failed
* to convert parameters into {@link IonValue}.
*/
public static void updateVehicleRegistration(final TransactionExecutor txn, final String vin, final String documentId) {
try {
log.info("Updating primary owner for vehicle with Vin: {}...", vin);
final String query = "UPDATE VehicleRegistration AS v SET v.Owners.PrimaryOwner = ? WHERE v.VIN = ?";
final List parameters = new ArrayList<>();
parameters.add(Constants.MAPPER.writeValueAsIonValue(new Owner(documentId)));
parameters.add(Constants.MAPPER.writeValueAsIonValue(vin));
Result result = txn.execute(query, parameters);
ScanTable.printDocuments(result);
if (result.isEmpty()) {
throw new IllegalStateException("Unable to transfer vehicle, could not find registration.");
} else {
log.info("Successfully transferred vehicle with VIN '{}' to new owner.", vin);
}
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final String vin = SampleData.VEHICLES.get(0).getVin();
final String primaryOwnerGovId = SampleData.PEOPLE.get(0).getGovId();
final String newPrimaryOwnerGovId = SampleData.PEOPLE.get(1).getGovId();
ConnectToLedger.getDriver().execute(txn -> {
final Person primaryOwner = findPrimaryOwnerForVehicle(txn, vin);
if (!primaryOwner.getGovId().equals(primaryOwnerGovId)) {
// Verify the primary owner.
throw new IllegalStateException("Incorrect primary owner identified for vehicle, unable to transfer.");
}
final String newOwner = Person.getDocumentIdByGovId(txn, newPrimaryOwnerGovId);
updateVehicleRegistration(txn, vin, newOwner);
});
log.info("Successfully transferred vehicle ownership!");
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonReader;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonValue;
import com.amazon.ion.system.IonReaderBuilder;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.Owner;
import software.amazon.qldb.tutorial.model.Person;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Find primary owner for a particular vehicle's VIN.
* Transfer to another primary owner for a particular vehicle's VIN.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class TransferVehicleOwnership {
public static final Logger log = LoggerFactory.getLogger(TransferVehicleOwnership.class);
private TransferVehicleOwnership() { }
/**
* Query a driver's information using the given ID.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param documentId
* The unique ID of a document in the Person table.
* @return a {@link Person} object.
* @throws IllegalStateException if failed to convert parameter into {@link IonValue}.
*/
public static Person findPersonFromDocumentId(final TransactionExecutor txn, final String documentId) {
try {
log.info("Finding person for documentId: {}...", documentId);
final String query = "SELECT p.* FROM Person AS p BY pid WHERE pid = ?";
Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId));
if (result.isEmpty()) {
throw new IllegalStateException("Unable to find person with ID: " + documentId);
}
return Constants.MAPPER.readValue(result.iterator().next(), Person.class);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Find the primary owner for the given VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @return a {@link Person} object.
* @throws IllegalStateException if failed to convert parameter into {@link IonValue}.
*/
public static Person findPrimaryOwnerForVehicle(final TransactionExecutor txn, final String vin) {
try {
log.info("Finding primary owner for vehicle with Vin: {}...", vin);
final String query = "SELECT Owners.PrimaryOwner.PersonId FROM VehicleRegistration AS v WHERE v.VIN = ?";
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin));
Result result = txn.execute(query, parameters);
final List documents = ScanTable.toIonStructs(result);
ScanTable.printDocuments(documents);
if (documents.isEmpty()) {
throw new IllegalStateException("Unable to find registrations with VIN: " + vin);
}
final IonReader reader = IonReaderBuilder.standard().build(documents.get(0));
final String personId = Constants.MAPPER.readValue(reader, LinkedHashMap.class).get("PersonId").toString();
return findPersonFromDocumentId(txn, personId);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Update the primary owner for a vehicle registration with the given documentId.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @param documentId
* New PersonId for the primary owner.
* @throws IllegalStateException if no vehicle registration was found using the given document ID and VIN, or if failed
* to convert parameters into {@link IonValue}.
*/
public static void updateVehicleRegistration(final TransactionExecutor txn, final String vin, final String documentId) {
try {
log.info("Updating primary owner for vehicle with Vin: {}...", vin);
final String query = "UPDATE VehicleRegistration AS v SET v.Owners.PrimaryOwner = ? WHERE v.VIN = ?";
final List parameters = new ArrayList<>();
parameters.add(Constants.MAPPER.writeValueAsIonValue(new Owner(documentId)));
parameters.add(Constants.MAPPER.writeValueAsIonValue(vin));
Result result = txn.execute(query, parameters);
ScanTable.printDocuments(result);
if (result.isEmpty()) {
throw new IllegalStateException("Unable to transfer vehicle, could not find registration.");
} else {
log.info("Successfully transferred vehicle with VIN '{}' to new owner.", vin);
}
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final String vin = SampleData.VEHICLES.get(0).getVin();
final String primaryOwnerGovId = SampleData.PEOPLE.get(0).getGovId();
final String newPrimaryOwnerGovId = SampleData.PEOPLE.get(1).getGovId();
ConnectToLedger.getDriver().execute(txn -> {
final Person primaryOwner = findPrimaryOwnerForVehicle(txn, vin);
if (!primaryOwner.getGovId().equals(primaryOwnerGovId)) {
// Verify the primary owner.
throw new IllegalStateException("Incorrect primary owner identified for vehicle, unable to transfer.");
}
final String newOwner = Person.getDocumentIdByGovId(txn, newPrimaryOwnerGovId);
updateVehicleRegistration(txn, vin, newOwner);
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
log.info("Successfully transferred vehicle ownership!");
}
}
```
------
1. 次のプログラム (`AddSecondaryOwner.java`) をコンパイルおよび実行して、台帳で VIN が `KM8SRDHF6EU074761` の車両に第二所有者を追加します。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.io.IOException;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazon.ion.IonValue;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.Owner;
import software.amazon.qldb.tutorial.model.Owners;
import software.amazon.qldb.tutorial.model.Person;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Finds and adds secondary owners for a vehicle.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class AddSecondaryOwner {
public static final Logger log = LoggerFactory.getLogger(AddSecondaryOwner.class);
private AddSecondaryOwner() { }
/**
* Check whether a secondary owner has already been registered for the given VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @param secondaryOwnerId
* The secondary owner to add.
* @return {@code true} if the given secondary owner has already been registered, {@code false} otherwise.
* @throws IllegalStateException if failed to convert VIN to an {@link IonValue}.
*/
public static boolean isSecondaryOwnerForVehicle(final TransactionExecutor txn, final String vin,
final String secondaryOwnerId) {
try {
log.info("Finding secondary owners for vehicle with VIN: {}...", vin);
final String query = "SELECT Owners.SecondaryOwners FROM VehicleRegistration AS v WHERE v.VIN = ?";
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin));
final Result result = txn.execute(query, parameters);
final Iterator itr = result.iterator();
if (!itr.hasNext()) {
return false;
}
final Owners owners = Constants.MAPPER.readValue(itr.next(), Owners.class);
if (null != owners.getSecondaryOwners()) {
for (Owner owner : owners.getSecondaryOwners()) {
if (secondaryOwnerId.equalsIgnoreCase(owner.getPersonId())) {
return true;
}
}
}
return false;
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Adds a secondary owner for the specified VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @param secondaryOwner
* The secondary owner to add.
* @throws IllegalStateException if failed to convert parameter into an {@link IonValue}.
*/
public static void addSecondaryOwnerForVin(final TransactionExecutor txn, final String vin,
final String secondaryOwner) {
try {
log.info("Inserting secondary owner for vehicle with VIN: {}...", vin);
final String query = String.format("FROM VehicleRegistration AS v WHERE v.VIN = ?" +
"INSERT INTO v.Owners.SecondaryOwners VALUE ?");
final IonValue newOwner = Constants.MAPPER.writeValueAsIonValue(new Owner(secondaryOwner));
final IonValue vinAsIonValue = Constants.MAPPER.writeValueAsIonValue(vin);
Result result = txn.execute(query, vinAsIonValue, newOwner);
log.info("VehicleRegistration Document IDs which had secondary owners added: ");
ScanTable.printDocuments(result);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final String vin = SampleData.VEHICLES.get(1).getVin();
final String govId = SampleData.PEOPLE.get(0).getGovId();
ConnectToLedger.getDriver().execute(txn -> {
final String documentId = Person.getDocumentIdByGovId(txn, govId);
if (isSecondaryOwnerForVehicle(txn, vin, documentId)) {
log.info("Person with ID {} has already been added as a secondary owner of this vehicle.", govId);
} else {
addSecondaryOwnerForVin(txn, vin, documentId);
}
});
log.info("Secondary owners successfully updated.");
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.io.IOException;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazon.ion.IonValue;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.Owner;
import software.amazon.qldb.tutorial.model.Owners;
import software.amazon.qldb.tutorial.model.Person;
import software.amazon.qldb.tutorial.model.SampleData;
/**
* Finds and adds secondary owners for a vehicle.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class AddSecondaryOwner {
public static final Logger log = LoggerFactory.getLogger(AddSecondaryOwner.class);
private AddSecondaryOwner() { }
/**
* Check whether a secondary owner has already been registered for the given VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @param secondaryOwnerId
* The secondary owner to add.
* @return {@code true} if the given secondary owner has already been registered, {@code false} otherwise.
* @throws IllegalStateException if failed to convert VIN to an {@link IonValue}.
*/
public static boolean isSecondaryOwnerForVehicle(final TransactionExecutor txn, final String vin,
final String secondaryOwnerId) {
try {
log.info("Finding secondary owners for vehicle with VIN: {}...", vin);
final String query = "SELECT Owners.SecondaryOwners FROM VehicleRegistration AS v WHERE v.VIN = ?";
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin));
final Result result = txn.execute(query, parameters);
final Iterator itr = result.iterator();
if (!itr.hasNext()) {
return false;
}
final Owners owners = Constants.MAPPER.readValue(itr.next(), Owners.class);
if (null != owners.getSecondaryOwners()) {
for (Owner owner : owners.getSecondaryOwners()) {
if (secondaryOwnerId.equalsIgnoreCase(owner.getPersonId())) {
return true;
}
}
}
return false;
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Adds a secondary owner for the specified VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* Unique VIN for a vehicle.
* @param secondaryOwner
* The secondary owner to add.
* @throws IllegalStateException if failed to convert parameter into an {@link IonValue}.
*/
public static void addSecondaryOwnerForVin(final TransactionExecutor txn, final String vin,
final String secondaryOwner) {
try {
log.info("Inserting secondary owner for vehicle with VIN: {}...", vin);
final String query = String.format("FROM VehicleRegistration AS v WHERE v.VIN = '%s' " +
"INSERT INTO v.Owners.SecondaryOwners VALUE ?", vin);
final IonValue newOwner = Constants.MAPPER.writeValueAsIonValue(new Owner(secondaryOwner));
Result result = txn.execute(query, newOwner);
log.info("VehicleRegistration Document IDs which had secondary owners added: ");
ScanTable.printDocuments(result);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final String vin = SampleData.VEHICLES.get(1).getVin();
final String govId = SampleData.PEOPLE.get(0).getGovId();
ConnectToLedger.getDriver().execute(txn -> {
final String documentId = Person.getDocumentIdByGovId(txn, govId);
if (isSecondaryOwnerForVehicle(txn, vin, documentId)) {
log.info("Person with ID {} has already been added as a secondary owner of this vehicle.", govId);
} else {
addSecondaryOwnerForVin(txn, vin, documentId);
}
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
log.info("Secondary owners successfully updated.");
}
}
```
------
これらの変更を `vehicle-registration` 台帳で確認するには、「[ステップ 6: ドキュメントのリビジョン履歴を表示する](getting-started.java.step-6.md)」を参照してください。
# ステップ 6: ドキュメントのリビジョン履歴を表示する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
前のステップで車両の登録データを変更した後、登録されているすべての所有者とその他の更新されたフィールドの履歴に対してクエリを実行できます。このステップでは、`vehicle-registration` 台帳の `VehicleRegistration` テーブルに含まれているドキュメントのリビジョン履歴のクエリを実行します。
**リビジョン履歴を表示するには**
1. 次のプログラムを確認します (`QueryHistory.java`)。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.io.IOException;
import java.time.Instant;
import java.time.temporal.ChronoUnit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazon.ion.IonValue;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
import software.amazon.qldb.tutorial.model.VehicleRegistration;
/**
* Query a table's history for a particular set of documents.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class QueryHistory {
public static final Logger log = LoggerFactory.getLogger(QueryHistory.class);
private static final int THREE_MONTHS = 90;
private QueryHistory() { }
/**
* In this example, query the 'VehicleRegistration' history table to find all previous primary owners for a VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* VIN to find previous primary owners for.
* @param query
* The query to find previous primary owners.
* @throws IllegalStateException if failed to convert document ID to an {@link IonValue}.
*/
public static void previousPrimaryOwners(final TransactionExecutor txn, final String vin, final String query) {
try {
final String docId = VehicleRegistration.getDocumentIdByVin(txn, vin);
log.info("Querying the 'VehicleRegistration' table's history using VIN: {}...", vin);
final Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(docId));
ScanTable.printDocuments(result);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final String threeMonthsAgo = Instant.now().minus(THREE_MONTHS, ChronoUnit.DAYS).toString();
final String query = String.format("SELECT data.Owners.PrimaryOwner, metadata.version "
+ "FROM history(VehicleRegistration, `%s`) "
+ "AS h WHERE h.metadata.id = ?", threeMonthsAgo);
ConnectToLedger.getDriver().execute(txn -> {
final String vin = SampleData.VEHICLES.get(0).getVin();
previousPrimaryOwners(txn, vin, query);
});
log.info("Successfully queried history.");
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonValue;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.QldbSession;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
import software.amazon.qldb.tutorial.model.VehicleRegistration;
import java.io.IOException;
import java.time.Instant;
import java.time.temporal.ChronoUnit;
import java.util.Collections;
import java.util.List;
/**
* Query a table's history for a particular set of documents.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class QueryHistory {
public static final Logger log = LoggerFactory.getLogger(QueryHistory.class);
private static final int THREE_MONTHS = 90;
private QueryHistory() { }
/**
* In this example, query the 'VehicleRegistration' history table to find all previous primary owners for a VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* VIN to find previous primary owners for.
* @param query
* The query to find previous primary owners.
* @throws IllegalStateException if failed to convert document ID to an {@link IonValue}.
*/
public static void previousPrimaryOwners(final TransactionExecutor txn, final String vin, final String query) {
try {
final String docId = VehicleRegistration.getDocumentIdByVin(txn, vin);
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(docId));
log.info("Querying the 'VehicleRegistration' table's history using VIN: {}...", vin);
final Result result = txn.execute(query, parameters);
ScanTable.printDocuments(result);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
public static void main(final String... args) {
final String threeMonthsAgo = Instant.now().minus(THREE_MONTHS, ChronoUnit.DAYS).toString();
final String query = String.format("SELECT data.Owners.PrimaryOwner, metadata.version "
+ "FROM history(VehicleRegistration, `%s`) "
+ "AS h WHERE h.metadata.id = ?", threeMonthsAgo);
ConnectToLedger.getDriver().execute(txn -> {
final String vin = SampleData.VEHICLES.get(0).getVin();
previousPrimaryOwners(txn, vin, query);
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
log.info("Successfully queried history.");
}
}
```
------
**注記**
以下の構文で組み込みの「[履歴関数](working.history.md#working.history.function)」のクエリを実行することで、ドキュメントのリビジョン履歴を表示できます。
```
SELECT * FROM history( table_name [, `start-time` [, `end-time` ] ] ) AS h
[ WHERE h.metadata.id = 'id' ]
```
*start-time* および *end-time* はいずれもオプションです。これらは、バックティック (``...``) で示すことができる Amazon Ion リテラル値です。詳細については、「[Amazon QLDB での PartiQL による Ion のクエリ](ql-reference.query.md)」を参照してください。
ベストプラクティスとして、履歴クエリは日付範囲 (*start-time* および *end-time*) とドキュメント ID (`metadata.id`) の両方で修飾します。QLDB はトランザクション内の `SELECT` クエリを処理します。これらは、[トランザクションタイムアウト制限](limits.md#limits.fixed)が適用されます。
QLDB 履歴はドキュメント ID によってインデックス付けされるため、現時点では追加の履歴インデックスを作成することはできません。開始時刻と終了時刻を含む履歴クエリでは、日付範囲修飾のメリットが得られます。
1. `QueryHistory.java` プログラムをコンパイルおよび実行して、VIN が `1N4AL11D75C109151` の `VehicleRegistration` ドキュメントのリビジョン履歴をクエリします。
`vehicle-registration` 台帳のドキュメントリビジョンを暗号的に検証するには、「[ステップ 7: 台帳内のドキュメントを検証する](getting-started.java.step-7.md)」に進みます。
# ステップ 7: 台帳内のドキュメントを検証する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
Amazon QLDB では、SHA-256 の暗号的ハッシュを使用して、台帳のジャーナルのドキュメントの整合性を効率的に検証できます。検証と暗号的ハッシュが QLDB でどのように機能するかについては、「[Amazon QLDB でのデータ検証](verification.md)」を参照してください。
このステップでは、`vehicle-registration` 台帳の `VehicleRegistration` テーブルのドキュメントリビジョンを確認します。まず、ダイジェストをリクエストします。ダイジェストは出力ファイルとして返され、台帳の変更履歴全体の署名として機能します。次に、そのダイジェストに関連するリビジョンの証明をリクエストします。この証明を使用して、すべての検証チェックに合格すると、リビジョンの整合性が検証されます。
**ドキュメントのリビジョンを検証するには**
1. 以下の `.java` ファイルを確認します。これらのファイルは、検証に必要な QLDB オブジェクトと、Ion 値および文字列値のヘルパーメソッドを含むユーティリティクラスを表します。
1. `BlockAddress.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import java.util.Objects;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
/**
* Represents the BlockAddress field of a QLDB document.
*/
public final class BlockAddress {
private static final Logger log = LoggerFactory.getLogger(BlockAddress.class);
private final String strandId;
private final long sequenceNo;
@JsonCreator
public BlockAddress(@JsonProperty("strandId") final String strandId,
@JsonProperty("sequenceNo") final long sequenceNo) {
this.strandId = strandId;
this.sequenceNo = sequenceNo;
}
public long getSequenceNo() {
return sequenceNo;
}
public String getStrandId() {
return strandId;
}
@Override
public String toString() {
return "BlockAddress{"
+ "strandId='" + strandId + '\''
+ ", sequenceNo=" + sequenceNo
+ '}';
}
@Override
public boolean equals(final Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
BlockAddress that = (BlockAddress) o;
return sequenceNo == that.sequenceNo
&& strandId.equals(that.strandId);
}
@Override
public int hashCode() {
// CHECKSTYLE:OFF - Disabling as we are generating a hashCode of multiple properties.
return Objects.hash(strandId, sequenceNo);
// CHECKSTYLE:ON
}
}
```
1. `Proof.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.amazon.ion.IonReader;
import com.amazon.ion.IonSystem;
import com.amazon.ion.system.IonSystemBuilder;
import com.amazonaws.services.qldb.model.GetRevisionRequest;
import com.amazonaws.services.qldb.model.GetRevisionResult;
import java.util.ArrayList;
import java.util.List;
/**
* A Java representation of the {@link Proof} object.
* Returned from the {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision(GetRevisionRequest)} api.
*/
public final class Proof {
private static final IonSystem SYSTEM = IonSystemBuilder.standard().build();
private List internalHashes;
public Proof(final List internalHashes) {
this.internalHashes = internalHashes;
}
public List getInternalHashes() {
return internalHashes;
}
/**
* Decodes a {@link Proof} from an ion text String. This ion text is returned in
* a {@link GetRevisionResult#getProof()}
*
* @param ionText
* The ion text representing a {@link Proof} object.
* @return {@link JournalBlock} parsed from the ion text.
* @throws IllegalStateException if failed to parse the {@link Proof} object from the given ion text.
*/
public static Proof fromBlob(final String ionText) {
try {
IonReader reader = SYSTEM.newReader(ionText);
List list = new ArrayList<>();
reader.next();
reader.stepIn();
while (reader.next() != null) {
list.add(reader.newBytes());
}
return new Proof(list);
} catch (Exception e) {
throw new IllegalStateException("Failed to parse a Proof from byte array");
}
}
}
```
1. `QldbIonUtils.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.amazon.ion.IonReader;
import com.amazon.ion.IonValue;
import com.amazon.ionhash.IonHashReader;
import com.amazon.ionhash.IonHashReaderBuilder;
import com.amazon.ionhash.MessageDigestIonHasherProvider;
import software.amazon.qldb.tutorial.Constants;
public class QldbIonUtils {
private static MessageDigestIonHasherProvider ionHasherProvider = new MessageDigestIonHasherProvider("SHA-256");
private QldbIonUtils() {}
/**
* Builds a hash value from the given {@link IonValue}.
*
* @param ionValue
* The {@link IonValue} to hash.
* @return a byte array representing the hash value.
*/
public static byte[] hashIonValue(final IonValue ionValue) {
IonReader reader = Constants.SYSTEM.newReader(ionValue);
IonHashReader hashReader = IonHashReaderBuilder.standard()
.withHasherProvider(ionHasherProvider)
.withReader(reader)
.build();
while (hashReader.next() != null) { }
return hashReader.digest();
}
}
```
1. `QldbStringUtils.java`
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.amazon.ion.IonWriter;
import com.amazon.ion.system.IonReaderBuilder;
import com.amazon.ion.system.IonTextWriterBuilder;
import com.amazonaws.services.qldb.model.GetBlockResult;
import com.amazonaws.services.qldb.model.GetDigestResult;
import com.amazonaws.services.qldb.model.ValueHolder;
import java.io.IOException;
/**
* Helper methods to pretty-print certain QLDB response types.
*/
public class QldbStringUtils {
private QldbStringUtils() {}
/**
* Returns the string representation of a given {@link ValueHolder}.
* Adapted from the AWS SDK autogenerated {@code toString()} method, with sensitive values un-redacted.
* Additionally, this method pretty-prints any IonText included in the {@link ValueHolder}.
*
* @param valueHolder the {@link ValueHolder} to convert to a String.
* @return the String representation of the supplied {@link ValueHolder}.
*/
public static String toUnredactedString(ValueHolder valueHolder) {
StringBuilder sb = new StringBuilder();
sb.append("{");
if (valueHolder.getIonText() != null) {
sb.append("IonText: ");
IonWriter prettyWriter = IonTextWriterBuilder.pretty().build(sb);
try {
prettyWriter.writeValues(IonReaderBuilder.standard().build(valueHolder.getIonText()));
} catch (IOException ioe) {
sb.append("**Exception while printing this IonText**");
}
}
sb.append("}");
return sb.toString();
}
/**
* Returns the string representation of a given {@link GetBlockResult}.
* Adapted from the AWS SDK autogenerated {@code toString()} method, with sensitive values un-redacted.
*
* @param getBlockResult the {@link GetBlockResult} to convert to a String.
* @return the String representation of the supplied {@link GetBlockResult}.
*/
public static String toUnredactedString(GetBlockResult getBlockResult) {
StringBuilder sb = new StringBuilder();
sb.append("{");
if (getBlockResult.getBlock() != null) {
sb.append("Block: ").append(toUnredactedString(getBlockResult.getBlock())).append(",");
}
if (getBlockResult.getProof() != null) {
sb.append("Proof: ").append(toUnredactedString(getBlockResult.getProof()));
}
sb.append("}");
return sb.toString();
}
/**
* Returns the string representation of a given {@link GetDigestResult}.
* Adapted from the AWS SDK autogenerated {@code toString()} method, with sensitive values un-redacted.
*
* @param getDigestResult the {@link GetDigestResult} to convert to a String.
* @return the String representation of the supplied {@link GetDigestResult}.
*/
public static String toUnredactedString(GetDigestResult getDigestResult) {
StringBuilder sb = new StringBuilder();
sb.append("{");
if (getDigestResult.getDigest() != null) {
sb.append("Digest: ").append(getDigestResult.getDigest()).append(",");
}
if (getDigestResult.getDigestTipAddress() != null) {
sb.append("DigestTipAddress: ").append(toUnredactedString(getDigestResult.getDigestTipAddress()));
}
sb.append("}");
return sb.toString();
}
}
```
1. `Verifier.java`
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.ThreadLocalRandom;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazonaws.util.Base64;
import software.amazon.qldb.tutorial.qldb.Proof;
/**
* Encapsulates the logic to verify the integrity of revisions or blocks in a QLDB ledger.
*
* The main entry point is {@link #verify(byte[], byte[], String)}.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class Verifier {
public static final Logger log = LoggerFactory.getLogger(Verifier.class);
private static final int HASH_LENGTH = 32;
private static final int UPPER_BOUND = 8;
/**
* Compares two hashes by their signed byte values in little-endian order.
*/
private static Comparator hashComparator = (h1, h2) -> {
if (h1.length != HASH_LENGTH || h2.length != HASH_LENGTH) {
throw new IllegalArgumentException("Invalid hash.");
}
for (int i = h1.length - 1; i >= 0; i--) {
int byteEqual = Byte.compare(h1[i], h2[i]);
if (byteEqual != 0) {
return byteEqual;
}
}
return 0;
};
private Verifier() { }
/**
* Verify the integrity of a document with respect to a QLDB ledger digest.
*
* The verification algorithm includes the following steps:
*
* 1. {@link #buildCandidateDigest(Proof, byte[])} build the candidate digest from the internal hashes
* in the {@link Proof}.
* 2. Check that the {@code candidateLedgerDigest} is equal to the {@code ledgerDigest}.
*
* @param documentHash
* The hash of the document to be verified.
* @param digest
* The QLDB ledger digest. This digest should have been retrieved using
* {@link com.amazonaws.services.qldb.AmazonQLDB#getDigest}
* @param proofBlob
* The ion encoded bytes representing the {@link Proof} associated with the supplied
* {@code digestTipAddress} and {@code address} retrieved using
* {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}.
* @return {@code true} if the record is verified or {@code false} if it is not verified.
*/
public static boolean verify(
final byte[] documentHash,
final byte[] digest,
final String proofBlob
) {
Proof proof = Proof.fromBlob(proofBlob);
byte[] candidateDigest = buildCandidateDigest(proof, documentHash);
return Arrays.equals(digest, candidateDigest);
}
/**
* Build the candidate digest representing the entire ledger from the internal hashes of the {@link Proof}.
*
* @param proof
* A Java representation of {@link Proof}
* returned from {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}.
* @param leafHash
* Leaf hash to build the candidate digest with.
* @return a byte array of the candidate digest.
*/
private static byte[] buildCandidateDigest(final Proof proof, final byte[] leafHash) {
return calculateRootHashFromInternalHashes(proof.getInternalHashes(), leafHash);
}
/**
* Get a new instance of {@link MessageDigest} using the SHA-256 algorithm.
*
* @return an instance of {@link MessageDigest}.
* @throws IllegalStateException if the algorithm is not available on the current JVM.
*/
static MessageDigest newMessageDigest() {
try {
return MessageDigest.getInstance("SHA-256");
} catch (NoSuchAlgorithmException e) {
log.error("Failed to create SHA-256 MessageDigest", e);
throw new IllegalStateException("SHA-256 message digest is unavailable", e);
}
}
/**
* Takes two hashes, sorts them, concatenates them, and then returns the
* hash of the concatenated array.
*
* @param h1
* Byte array containing one of the hashes to compare.
* @param h2
* Byte array containing one of the hashes to compare.
* @return the concatenated array of hashes.
*/
public static byte[] dot(final byte[] h1, final byte[] h2) {
if (h1.length == 0) {
return h2;
}
if (h2.length == 0) {
return h1;
}
byte[] concatenated = new byte[h1.length + h2.length];
if (hashComparator.compare(h1, h2) < 0) {
System.arraycopy(h1, 0, concatenated, 0, h1.length);
System.arraycopy(h2, 0, concatenated, h1.length, h2.length);
} else {
System.arraycopy(h2, 0, concatenated, 0, h2.length);
System.arraycopy(h1, 0, concatenated, h2.length, h1.length);
}
MessageDigest messageDigest = newMessageDigest();
messageDigest.update(concatenated);
return messageDigest.digest();
}
/**
* Starting with the provided {@code leafHash} combined with the provided {@code internalHashes}
* pairwise until only the root hash remains.
*
* @param internalHashes
* Internal hashes of Merkle tree.
* @param leafHash
* Leaf hashes of Merkle tree.
* @return the root hash.
*/
private static byte[] calculateRootHashFromInternalHashes(final List internalHashes, final byte[] leafHash) {
return internalHashes.stream().reduce(leafHash, Verifier::dot);
}
/**
* Flip a single random bit in the given byte array. This method is used to demonstrate
* QLDB's verification features.
*
* @param original
* The original byte array.
* @return the altered byte array with a single random bit changed.
*/
public static byte[] flipRandomBit(final byte[] original) {
if (original.length == 0) {
throw new IllegalArgumentException("Array cannot be empty!");
}
int alteredPosition = ThreadLocalRandom.current().nextInt(original.length);
int b = ThreadLocalRandom.current().nextInt(UPPER_BOUND);
byte[] altered = new byte[original.length];
System.arraycopy(original, 0, altered, 0, original.length);
altered[alteredPosition] = (byte) (altered[alteredPosition] ^ (1 << b));
return altered;
}
public static String toBase64(byte[] arr) {
return new String(Base64.encode(arr), StandardCharsets.UTF_8);
}
/**
* Convert a {@link ByteBuffer} into byte array.
*
* @param buffer
* The {@link ByteBuffer} to convert.
* @return the converted byte array.
*/
public static byte[] convertByteBufferToByteArray(final ByteBuffer buffer) {
byte[] arr = new byte[buffer.remaining()];
buffer.get(arr);
return arr;
}
/**
* Calculates the root hash from a list of hashes that represent the base of a Merkle tree.
*
* @param hashes
* The list of byte arrays representing hashes making up base of a Merkle tree.
* @return a byte array that is the root hash of the given list of hashes.
*/
public static byte[] calculateMerkleTreeRootHash(List hashes) {
if (hashes.isEmpty()) {
return new byte[0];
}
List remaining = combineLeafHashes(hashes);
while (remaining.size() > 1) {
remaining = combineLeafHashes(remaining);
}
return remaining.get(0);
}
private static List combineLeafHashes(List hashes) {
List combinedHashes = new ArrayList<>();
Iterator it = hashes.stream().iterator();
while (it.hasNext()) {
byte[] left = it.next();
if (it.hasNext()) {
byte[] right = it.next();
byte[] combined = dot(left, right);
combinedHashes.add(combined);
} else {
combinedHashes.add(left);
}
}
return combinedHashes;
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.util.Base64;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.tutorial.qldb.Proof;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.*;
import java.util.concurrent.ThreadLocalRandom;
/**
* Encapsulates the logic to verify the integrity of revisions or blocks in a QLDB ledger.
*
* The main entry point is {@link #verify(byte[], byte[], String)}.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class Verifier {
public static final Logger log = LoggerFactory.getLogger(Verifier.class);
private static final int HASH_LENGTH = 32;
private static final int UPPER_BOUND = 8;
/**
* Compares two hashes by their signed byte values in little-endian order.
*/
private static Comparator hashComparator = (h1, h2) -> {
if (h1.length != HASH_LENGTH || h2.length != HASH_LENGTH) {
throw new IllegalArgumentException("Invalid hash.");
}
for (int i = h1.length - 1; i >= 0; i--) {
int byteEqual = Byte.compare(h1[i], h2[i]);
if (byteEqual != 0) {
return byteEqual;
}
}
return 0;
};
private Verifier() { }
/**
* Verify the integrity of a document with respect to a QLDB ledger digest.
*
* The verification algorithm includes the following steps:
*
* 1. {@link #buildCandidateDigest(Proof, byte[])} build the candidate digest from the internal hashes
* in the {@link Proof}.
* 2. Check that the {@code candidateLedgerDigest} is equal to the {@code ledgerDigest}.
*
* @param documentHash
* The hash of the document to be verified.
* @param digest
* The QLDB ledger digest. This digest should have been retrieved using
* {@link com.amazonaws.services.qldb.AmazonQLDB#getDigest}
* @param proofBlob
* The ion encoded bytes representing the {@link Proof} associated with the supplied
* {@code digestTipAddress} and {@code address} retrieved using
* {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}.
* @return {@code true} if the record is verified or {@code false} if it is not verified.
*/
public static boolean verify(
final byte[] documentHash,
final byte[] digest,
final String proofBlob
) {
Proof proof = Proof.fromBlob(proofBlob);
byte[] candidateDigest = buildCandidateDigest(proof, documentHash);
return Arrays.equals(digest, candidateDigest);
}
/**
* Build the candidate digest representing the entire ledger from the internal hashes of the {@link Proof}.
*
* @param proof
* A Java representation of {@link Proof}
* returned from {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}.
* @param leafHash
* Leaf hash to build the candidate digest with.
* @return a byte array of the candidate digest.
*/
private static byte[] buildCandidateDigest(final Proof proof, final byte[] leafHash) {
return calculateRootHashFromInternalHashes(proof.getInternalHashes(), leafHash);
}
/**
* Get a new instance of {@link MessageDigest} using the SHA-256 algorithm.
*
* @return an instance of {@link MessageDigest}.
* @throws IllegalStateException if the algorithm is not available on the current JVM.
*/
static MessageDigest newMessageDigest() {
try {
return MessageDigest.getInstance("SHA-256");
} catch (NoSuchAlgorithmException e) {
log.error("Failed to create SHA-256 MessageDigest", e);
throw new IllegalStateException("SHA-256 message digest is unavailable", e);
}
}
/**
* Takes two hashes, sorts them, concatenates them, and then returns the
* hash of the concatenated array.
*
* @param h1
* Byte array containing one of the hashes to compare.
* @param h2
* Byte array containing one of the hashes to compare.
* @return the concatenated array of hashes.
*/
public static byte[] dot(final byte[] h1, final byte[] h2) {
if (h1.length == 0) {
return h2;
}
if (h2.length == 0) {
return h1;
}
byte[] concatenated = new byte[h1.length + h2.length];
if (hashComparator.compare(h1, h2) < 0) {
System.arraycopy(h1, 0, concatenated, 0, h1.length);
System.arraycopy(h2, 0, concatenated, h1.length, h2.length);
} else {
System.arraycopy(h2, 0, concatenated, 0, h2.length);
System.arraycopy(h1, 0, concatenated, h2.length, h1.length);
}
MessageDigest messageDigest = newMessageDigest();
messageDigest.update(concatenated);
return messageDigest.digest();
}
/**
* Starting with the provided {@code leafHash} combined with the provided {@code internalHashes}
* pairwise until only the root hash remains.
*
* @param internalHashes
* Internal hashes of Merkle tree.
* @param leafHash
* Leaf hashes of Merkle tree.
* @return the root hash.
*/
private static byte[] calculateRootHashFromInternalHashes(final List internalHashes, final byte[] leafHash) {
return internalHashes.stream().reduce(leafHash, Verifier::dot);
}
/**
* Flip a single random bit in the given byte array. This method is used to demonstrate
* QLDB's verification features.
*
* @param original
* The original byte array.
* @return the altered byte array with a single random bit changed.
*/
public static byte[] flipRandomBit(final byte[] original) {
if (original.length == 0) {
throw new IllegalArgumentException("Array cannot be empty!");
}
int alteredPosition = ThreadLocalRandom.current().nextInt(original.length);
int b = ThreadLocalRandom.current().nextInt(UPPER_BOUND);
byte[] altered = new byte[original.length];
System.arraycopy(original, 0, altered, 0, original.length);
altered[alteredPosition] = (byte) (altered[alteredPosition] ^ (1 << b));
return altered;
}
public static String toBase64(byte[] arr) {
return new String(Base64.encode(arr), StandardCharsets.UTF_8);
}
/**
* Convert a {@link ByteBuffer} into byte array.
*
* @param buffer
* The {@link ByteBuffer} to convert.
* @return the converted byte array.
*/
public static byte[] convertByteBufferToByteArray(final ByteBuffer buffer) {
byte[] arr = new byte[buffer.remaining()];
buffer.get(arr);
return arr;
}
/**
* Calculates the root hash from a list of hashes that represent the base of a Merkle tree.
*
* @param hashes
* The list of byte arrays representing hashes making up base of a Merkle tree.
* @return a byte array that is the root hash of the given list of hashes.
*/
public static byte[] calculateMerkleTreeRootHash(List hashes) {
if (hashes.isEmpty()) {
return new byte[0];
}
List remaining = combineLeafHashes(hashes);
while (remaining.size() > 1) {
remaining = combineLeafHashes(remaining);
}
return remaining.get(0);
}
private static List combineLeafHashes(List hashes) {
List combinedHashes = new ArrayList<>();
Iterator it = hashes.stream().iterator();
while (it.hasNext()) {
byte[] left = it.next();
if (it.hasNext()) {
byte[] right = it.next();
byte[] combined = dot(left, right);
combinedHashes.add(combined);
} else {
combinedHashes.add(left);
}
}
return combinedHashes;
}
}
```
------
1. 2 つの `.java` ファイル (`GetDigest.java` および `GetRevision.java`) を使用して、次の手順を実行します。
+ `vehicle-registration` 台帳に新しいダイジェストをリクエストします。
+ `VehicleRegistration` テーブルにドキュメントの各リビジョンの証明をリクエストします。
+ 返されたダイジェストと証明を使用して、ダイジェストを再計算することで、リビジョンを検証します。
`GetDigest.java` プログラムには、次のコードが含まれています。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.model.GetDigestRequest;
import com.amazonaws.services.qldb.model.GetDigestResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.tutorial.qldb.QldbStringUtils;
/**
* This is an example for retrieving the digest of a particular ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class GetDigest {
public static final Logger log = LoggerFactory.getLogger(GetDigest.class);
public static AmazonQLDB client = CreateLedger.getClient();
private GetDigest() { }
/**
* Calls {@link #getDigest(String)} for a ledger.
*
* @param args
* Arbitrary command-line arguments.
* @throws Exception if failed to get a ledger digest.
*/
public static void main(final String... args) throws Exception {
try {
getDigest(Constants.LEDGER_NAME);
} catch (Exception e) {
log.error("Unable to get a ledger digest!", e);
throw e;
}
}
/**
* Get the digest for the specified ledger.
*
* @param ledgerName
* The ledger to get digest from.
* @return {@link GetDigestResult}.
*/
public static GetDigestResult getDigest(final String ledgerName) {
log.info("Let's get the current digest of the ledger named {}.", ledgerName);
GetDigestRequest request = new GetDigestRequest()
.withName(ledgerName);
GetDigestResult result = client.getDigest(request);
log.info("Success. LedgerDigest: {}.", QldbStringUtils.toUnredactedString(result));
return result;
}
}
```
**注記**
`getDigest` メソッドを使用して、台帳のジャーナルの現在の*ティップ*を含むダイジェストをリクエストします。ジャーナルのティップとは、QLDB がリクエストを受けた時点でコミット済みの最新のブロックのことです。
`GetRevision.java` プログラムには、次のコードが含まれています。
------
#### [ 2.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonReader;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonSystem;
import com.amazon.ion.IonValue;
import com.amazon.ion.IonWriter;
import com.amazon.ion.system.IonReaderBuilder;
import com.amazon.ion.system.IonSystemBuilder;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.model.GetDigestResult;
import com.amazonaws.services.qldb.model.GetRevisionRequest;
import com.amazonaws.services.qldb.model.GetRevisionResult;
import com.amazonaws.services.qldb.model.ValueHolder;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.QldbDriver;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
import software.amazon.qldb.tutorial.qldb.BlockAddress;
import software.amazon.qldb.tutorial.qldb.QldbRevision;
import software.amazon.qldb.tutorial.qldb.QldbStringUtils;
/**
* Verify the integrity of a document revision in a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class GetRevision {
public static final Logger log = LoggerFactory.getLogger(GetRevision.class);
public static AmazonQLDB client = CreateLedger.getClient();
private static final IonSystem SYSTEM = IonSystemBuilder.standard().build();
private GetRevision() { }
public static void main(String... args) throws Exception {
final String vin = SampleData.REGISTRATIONS.get(0).getVin();
verifyRegistration(ConnectToLedger.getDriver(), Constants.LEDGER_NAME, vin);
}
/**
* Verify each version of the registration for the given VIN.
*
* @param driver
* A QLDB driver.
* @param ledgerName
* The ledger to get digest from.
* @param vin
* VIN to query the revision history of a specific registration with.
* @throws Exception if failed to verify digests.
* @throws AssertionError if document revision verification failed.
*/
public static void verifyRegistration(final QldbDriver driver, final String ledgerName, final String vin)
throws Exception {
log.info(String.format("Let's verify the registration with VIN=%s, in ledger=%s.", vin, ledgerName));
try {
log.info("First, let's get a digest.");
GetDigestResult digestResult = GetDigest.getDigest(ledgerName);
ValueHolder digestTipAddress = digestResult.getDigestTipAddress();
byte[] digestBytes = Verifier.convertByteBufferToByteArray(digestResult.getDigest());
log.info("Got a ledger digest. Digest end address={}, digest={}.",
QldbStringUtils.toUnredactedString(digestTipAddress),
Verifier.toBase64(digestBytes));
log.info(String.format("Next, let's query the registration with VIN=%s. "
+ "Then we can verify each version of the registration.", vin));
List documentsWithMetadataList = new ArrayList<>();
driver.execute(txn -> {
documentsWithMetadataList.addAll(queryRegistrationsByVin(txn, vin));
});
log.info("Registrations queried successfully!");
log.info(String.format("Found %s revisions of the registration with VIN=%s.",
documentsWithMetadataList.size(), vin));
for (IonStruct ionStruct : documentsWithMetadataList) {
QldbRevision document = QldbRevision.fromIon(ionStruct);
log.info(String.format("Let's verify the document: %s", document));
log.info("Let's get a proof for the document.");
GetRevisionResult proofResult = getRevision(
ledgerName,
document.getMetadata().getId(),
digestTipAddress,
document.getBlockAddress()
);
final IonValue proof = Constants.MAPPER.writeValueAsIonValue(proofResult.getProof());
final IonReader reader = IonReaderBuilder.standard().build(proof);
reader.next();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
IonWriter writer = SYSTEM.newBinaryWriter(baos);
writer.writeValue(reader);
writer.close();
baos.flush();
baos.close();
byte[] byteProof = baos.toByteArray();
log.info(String.format("Got back a proof: %s", Verifier.toBase64(byteProof)));
boolean verified = Verifier.verify(
document.getHash(),
digestBytes,
proofResult.getProof().getIonText()
);
if (!verified) {
throw new AssertionError("Document revision is not verified!");
} else {
log.info("Success! The document is verified");
}
byte[] alteredDigest = Verifier.flipRandomBit(digestBytes);
log.info(String.format("Flipping one bit in the digest and assert that the document is NOT verified. "
+ "The altered digest is: %s", Verifier.toBase64(alteredDigest)));
verified = Verifier.verify(
document.getHash(),
alteredDigest,
proofResult.getProof().getIonText()
);
if (verified) {
throw new AssertionError("Expected document to not be verified against altered digest.");
} else {
log.info("Success! As expected flipping a bit in the digest causes verification to fail.");
}
byte[] alteredDocumentHash = Verifier.flipRandomBit(document.getHash());
log.info(String.format("Flipping one bit in the document's hash and assert that it is NOT verified. "
+ "The altered document hash is: %s.", Verifier.toBase64(alteredDocumentHash)));
verified = Verifier.verify(
alteredDocumentHash,
digestBytes,
proofResult.getProof().getIonText()
);
if (verified) {
throw new AssertionError("Expected altered document hash to not be verified against digest.");
} else {
log.info("Success! As expected flipping a bit in the document hash causes verification to fail.");
}
}
} catch (Exception e) {
log.error("Failed to verify digests.", e);
throw e;
}
log.info(String.format("Finished verifying the registration with VIN=%s in ledger=%s.", vin, ledgerName));
}
/**
* Get the revision of a particular document specified by the given document ID and block address.
*
* @param ledgerName
* Name of the ledger containing the document.
* @param documentId
* Unique ID for the document to be verified, contained in the committed view of the document.
* @param digestTipAddress
* The latest block location covered by the digest.
* @param blockAddress
* The location of the block to request.
* @return the requested revision.
*/
public static GetRevisionResult getRevision(final String ledgerName, final String documentId,
final ValueHolder digestTipAddress, final BlockAddress blockAddress) {
try {
GetRevisionRequest request = new GetRevisionRequest()
.withName(ledgerName)
.withDigestTipAddress(digestTipAddress)
.withBlockAddress(new ValueHolder().withIonText(Constants.MAPPER.writeValueAsIonValue(blockAddress)
.toString()))
.withDocumentId(documentId);
return client.getRevision(request);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Query the registration history for the given VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* The unique VIN to query.
* @return a list of {@link IonStruct} representing the registration history.
* @throws IllegalStateException if failed to convert parameters into {@link IonValue}
*/
public static List queryRegistrationsByVin(final TransactionExecutor txn, final String vin) {
log.info(String.format("Let's query the 'VehicleRegistration' table for VIN: %s...", vin));
log.info("Let's query the 'VehicleRegistration' table for VIN: {}...", vin);
final String query = String.format("SELECT * FROM _ql_committed_%s WHERE data.VIN = ?",
Constants.VEHICLE_REGISTRATION_TABLE_NAME);
try {
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin));
final Result result = txn.execute(query, parameters);
List list = ScanTable.toIonStructs(result);
log.info(String.format("Found %d document(s)!", list.size()));
return list;
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
}
```
------
#### [ 1.x ]
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazon.ion.IonReader;
import com.amazon.ion.IonStruct;
import com.amazon.ion.IonValue;
import com.amazon.ion.IonWriter;
import com.amazon.ion.system.IonReaderBuilder;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.model.GetDigestResult;
import com.amazonaws.services.qldb.model.GetRevisionRequest;
import com.amazonaws.services.qldb.model.GetRevisionResult;
import com.amazonaws.services.qldb.model.ValueHolder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.QldbSession;
import software.amazon.qldb.Result;
import software.amazon.qldb.TransactionExecutor;
import software.amazon.qldb.tutorial.model.SampleData;
import software.amazon.qldb.tutorial.qldb.BlockAddress;
import software.amazon.qldb.tutorial.qldb.QldbRevision;
import software.amazon.qldb.tutorial.qldb.QldbStringUtils;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* Verify the integrity of a document revision in a QLDB ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class GetRevision {
public static final Logger log = LoggerFactory.getLogger(GetRevision.class);
public static AmazonQLDB client = CreateLedger.getClient();
private GetRevision() { }
public static void main(String... args) throws Exception {
final String vin = SampleData.REGISTRATIONS.get(0).getVin();
try (QldbSession qldbSession = ConnectToLedger.createQldbSession()) {
verifyRegistration(qldbSession, Constants.LEDGER_NAME, vin);
}
}
/**
* Verify each version of the registration for the given VIN.
*
* @param qldbSession
* A QLDB session.
* @param ledgerName
* The ledger to get digest from.
* @param vin
* VIN to query the revision history of a specific registration with.
* @throws Exception if failed to verify digests.
* @throws AssertionError if document revision verification failed.
*/
public static void verifyRegistration(final QldbSession qldbSession, final String ledgerName, final String vin)
throws Exception {
log.info(String.format("Let's verify the registration with VIN=%s, in ledger=%s.", vin, ledgerName));
try {
log.info("First, let's get a digest.");
GetDigestResult digestResult = GetDigest.getDigest(ledgerName);
ValueHolder digestTipAddress = digestResult.getDigestTipAddress();
byte[] digestBytes = Verifier.convertByteBufferToByteArray(digestResult.getDigest());
log.info("Got a ledger digest. Digest end address={}, digest={}.",
QldbStringUtils.toUnredactedString(digestTipAddress),
Verifier.toBase64(digestBytes));
log.info(String.format("Next, let's query the registration with VIN=%s. "
+ "Then we can verify each version of the registration.", vin));
List documentsWithMetadataList = new ArrayList<>();
qldbSession.execute(txn -> {
documentsWithMetadataList.addAll(queryRegistrationsByVin(txn, vin));
}, (retryAttempt) -> log.info("Retrying due to OCC conflict..."));
log.info("Registrations queried successfully!");
log.info(String.format("Found %s revisions of the registration with VIN=%s.",
documentsWithMetadataList.size(), vin));
for (IonStruct ionStruct : documentsWithMetadataList) {
QldbRevision document = QldbRevision.fromIon(ionStruct);
log.info(String.format("Let's verify the document: %s", document));
log.info("Let's get a proof for the document.");
GetRevisionResult proofResult = getRevision(
ledgerName,
document.getMetadata().getId(),
digestTipAddress,
document.getBlockAddress()
);
final IonValue proof = Constants.MAPPER.writeValueAsIonValue(proofResult.getProof());
final IonReader reader = IonReaderBuilder.standard().build(proof);
reader.next();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
IonWriter writer = Constants.SYSTEM.newBinaryWriter(baos);
writer.writeValue(reader);
writer.close();
baos.flush();
baos.close();
byte[] byteProof = baos.toByteArray();
log.info(String.format("Got back a proof: %s", Verifier.toBase64(byteProof)));
boolean verified = Verifier.verify(
document.getHash(),
digestBytes,
proofResult.getProof().getIonText()
);
if (!verified) {
throw new AssertionError("Document revision is not verified!");
} else {
log.info("Success! The document is verified");
}
byte[] alteredDigest = Verifier.flipRandomBit(digestBytes);
log.info(String.format("Flipping one bit in the digest and assert that the document is NOT verified. "
+ "The altered digest is: %s", Verifier.toBase64(alteredDigest)));
verified = Verifier.verify(
document.getHash(),
alteredDigest,
proofResult.getProof().getIonText()
);
if (verified) {
throw new AssertionError("Expected document to not be verified against altered digest.");
} else {
log.info("Success! As expected flipping a bit in the digest causes verification to fail.");
}
byte[] alteredDocumentHash = Verifier.flipRandomBit(document.getHash());
log.info(String.format("Flipping one bit in the document's hash and assert that it is NOT verified. "
+ "The altered document hash is: %s.", Verifier.toBase64(alteredDocumentHash)));
verified = Verifier.verify(
alteredDocumentHash,
digestBytes,
proofResult.getProof().getIonText()
);
if (verified) {
throw new AssertionError("Expected altered document hash to not be verified against digest.");
} else {
log.info("Success! As expected flipping a bit in the document hash causes verification to fail.");
}
}
} catch (Exception e) {
log.error("Failed to verify digests.", e);
throw e;
}
log.info(String.format("Finished verifying the registration with VIN=%s in ledger=%s.", vin, ledgerName));
}
/**
* Get the revision of a particular document specified by the given document ID and block address.
*
* @param ledgerName
* Name of the ledger containing the document.
* @param documentId
* Unique ID for the document to be verified, contained in the committed view of the document.
* @param digestTipAddress
* The latest block location covered by the digest.
* @param blockAddress
* The location of the block to request.
* @return the requested revision.
*/
public static GetRevisionResult getRevision(final String ledgerName, final String documentId,
final ValueHolder digestTipAddress, final BlockAddress blockAddress) {
try {
GetRevisionRequest request = new GetRevisionRequest()
.withName(ledgerName)
.withDigestTipAddress(digestTipAddress)
.withBlockAddress(new ValueHolder().withIonText(Constants.MAPPER.writeValueAsIonValue(blockAddress)
.toString()))
.withDocumentId(documentId);
return client.getRevision(request);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
/**
* Query the registration history for the given VIN.
*
* @param txn
* The {@link TransactionExecutor} for lambda execute.
* @param vin
* The unique VIN to query.
* @return a list of {@link IonStruct} representing the registration history.
* @throws IllegalStateException if failed to convert parameters into {@link IonValue}
*/
public static List queryRegistrationsByVin(final TransactionExecutor txn, final String vin) {
log.info(String.format("Let's query the 'VehicleRegistration' table for VIN: %s...", vin));
log.info("Let's query the 'VehicleRegistration' table for VIN: {}...", vin);
final String query = String.format("SELECT * FROM _ql_committed_%s WHERE data.VIN = ?",
Constants.VEHICLE_REGISTRATION_TABLE_NAME);
try {
final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin));
final Result result = txn.execute(query, parameters);
List list = ScanTable.toIonStructs(result);
log.info(String.format("Found %d document(s)!", list.size()));
return list;
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
}
```
------
**注記**
`getRevision` メソッドから、指定したドキュメントリビジョンの証明が返された後、このプログラムはクライアント側 API を使用してそのリビジョンを検証します。この API で使用されているアルゴリズムの概要については、「[証明を使用したダイジェストの再計算](verification.results.md#verification.results.recalc)」を参照してください。
1. `GetRevision.java` プログラムをコンパイルおよび実行して、VIN が `1N4AL11D75C109151` の `VehicleRegistration` ドキュメントを暗号的に検証します。
`vehicle-registration` 台帳でジャーナルデータをエクスポートして検証するには、「[ステップ 8: 元帳のジャーナルデータをエクスポートして検証する](getting-started.java.step-8.md)」に進みます。
# ステップ 8: 元帳のジャーナルデータをエクスポートして検証する
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
Amazon QLDB では、台帳のジャーナルのコンテンツには、データ保持、分析、監査などのさまざまな目的でアクセスできます。詳細については、「[Amazon QLDB からのジャーナルデータのエクスポート](export-journal.md)」を参照してください。
このステップでは、[ジャーナルブロック](journal-contents.md)を `vehicle-registration` 台帳から Amazon S3 バケットにエクスポートします。次に、エクスポートされたデータを使用して、ジャーナルブロックと各ブロック内の個々のハッシュコンポーネント間のハッシュチェーンを検証します。
使用する AWS Identity and Access Management (IAM) プリンシパルエンティティには、 に Amazon S3 バケットを作成するための十分な IAM アクセス許可が必要です AWS アカウント。詳細については、「[Amazon S3 ユーザーガイド](https://docs.aws.amazon.com/AmazonS3/latest/userguide/access-policy-language-overview.html)」の「**Amazon S3 でのポリシーとアクセス許可」を参照してください。また、QLDB が Simple Storage Service (Amazon S3) バケットにオブジェクトを書き込むことを許可するアクセス許可ポリシーがアタッチされた IAM ロールを作成するアクセス許可も必要です。詳細については、「[IAM ユーザーガイド](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_permissions-required.html)」の「**IAM リソースにアクセスするために必要な許可」を参照してください。
**ジャーナルデータをエクスポートして検証するには**
1. ジャーナルブロックとそのデータ内容を表す以下のファイル (`JournalBlock.java`) を確認します。これには、`verifyBlockHash()` という名前のメソッドが含まれています。これは、ブロックハッシュの各コンポーネントを計算する方法を示しています。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial.qldb;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.fasterxml.jackson.dataformat.ion.IonTimestampSerializers;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.tutorial.Constants;
import software.amazon.qldb.tutorial.Verifier;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.Date;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
import static java.nio.ByteBuffer.wrap;
/**
* Represents a JournalBlock that was recorded after executing a transaction
* in the ledger.
*/
public final class JournalBlock {
private static final Logger log = LoggerFactory.getLogger(JournalBlock.class);
private BlockAddress blockAddress;
private String transactionId;
@JsonSerialize(using = IonTimestampSerializers.IonTimestampJavaDateSerializer.class)
private Date blockTimestamp;
private byte[] blockHash;
private byte[] entriesHash;
private byte[] previousBlockHash;
private byte[][] entriesHashList;
private TransactionInfo transactionInfo;
private RedactionInfo redactionInfo;
private List revisions;
@JsonCreator
public JournalBlock(@JsonProperty("blockAddress") final BlockAddress blockAddress,
@JsonProperty("transactionId") final String transactionId,
@JsonProperty("blockTimestamp") final Date blockTimestamp,
@JsonProperty("blockHash") final byte[] blockHash,
@JsonProperty("entriesHash") final byte[] entriesHash,
@JsonProperty("previousBlockHash") final byte[] previousBlockHash,
@JsonProperty("entriesHashList") final byte[][] entriesHashList,
@JsonProperty("transactionInfo") final TransactionInfo transactionInfo,
@JsonProperty("redactionInfo") final RedactionInfo redactionInfo,
@JsonProperty("revisions") final List revisions) {
this.blockAddress = blockAddress;
this.transactionId = transactionId;
this.blockTimestamp = blockTimestamp;
this.blockHash = blockHash;
this.entriesHash = entriesHash;
this.previousBlockHash = previousBlockHash;
this.entriesHashList = entriesHashList;
this.transactionInfo = transactionInfo;
this.redactionInfo = redactionInfo;
this.revisions = revisions;
}
public BlockAddress getBlockAddress() {
return blockAddress;
}
public String getTransactionId() {
return transactionId;
}
public Date getBlockTimestamp() {
return blockTimestamp;
}
public byte[][] getEntriesHashList() {
return entriesHashList;
}
public TransactionInfo getTransactionInfo() {
return transactionInfo;
}
public RedactionInfo getRedactionInfo() {
return redactionInfo;
}
public List getRevisions() {
return revisions;
}
public byte[] getEntriesHash() {
return entriesHash;
}
public byte[] getBlockHash() {
return blockHash;
}
public byte[] getPreviousBlockHash() {
return previousBlockHash;
}
@Override
public String toString() {
return "JournalBlock{"
+ "blockAddress=" + blockAddress
+ ", transactionId='" + transactionId + '\''
+ ", blockTimestamp=" + blockTimestamp
+ ", blockHash=" + Arrays.toString(blockHash)
+ ", entriesHash=" + Arrays.toString(entriesHash)
+ ", previousBlockHash=" + Arrays.toString(previousBlockHash)
+ ", entriesHashList=" + Arrays.toString(entriesHashList)
+ ", transactionInfo=" + transactionInfo
+ ", redactionInfo=" + redactionInfo
+ ", revisions=" + revisions
+ '}';
}
@Override
public boolean equals(final Object o) {
if (this == o) {
return true;
}
if (!(o instanceof JournalBlock)) {
return false;
}
final JournalBlock that = (JournalBlock) o;
if (!getBlockAddress().equals(that.getBlockAddress())) {
return false;
}
if (!getTransactionId().equals(that.getTransactionId())) {
return false;
}
if (!getBlockTimestamp().equals(that.getBlockTimestamp())) {
return false;
}
if (!Arrays.equals(getBlockHash(), that.getBlockHash())) {
return false;
}
if (!Arrays.equals(getEntriesHash(), that.getEntriesHash())) {
return false;
}
if (!Arrays.equals(getPreviousBlockHash(), that.getPreviousBlockHash())) {
return false;
}
if (!Arrays.deepEquals(getEntriesHashList(), that.getEntriesHashList())) {
return false;
}
if (!getTransactionInfo().equals(that.getTransactionInfo())) {
return false;
}
if (getRedactionInfo() != null ? !getRedactionInfo().equals(that.getRedactionInfo()) : that.getRedactionInfo() != null) {
return false;
}
return getRevisions() != null ? getRevisions().equals(that.getRevisions()) : that.getRevisions() == null;
}
@Override
public int hashCode() {
int result = getBlockAddress().hashCode();
result = 31 * result + getTransactionId().hashCode();
result = 31 * result + getBlockTimestamp().hashCode();
result = 31 * result + Arrays.hashCode(getBlockHash());
result = 31 * result + Arrays.hashCode(getEntriesHash());
result = 31 * result + Arrays.hashCode(getPreviousBlockHash());
result = 31 * result + Arrays.deepHashCode(getEntriesHashList());
result = 31 * result + getTransactionInfo().hashCode();
result = 31 * result + (getRedactionInfo() != null ? getRedactionInfo().hashCode() : 0);
result = 31 * result + (getRevisions() != null ? getRevisions().hashCode() : 0);
return result;
}
/**
* This method validates that the hashes of the components of a journal block make up the block
* hash that is provided with the block itself.
*
* The components that contribute to the hash of the journal block consist of the following:
* - user transaction information (contained in [transactionInfo])
* - user redaction information (contained in [redactionInfo])
* - user revisions (contained in [revisions])
* - hashes of internal-only system metadata (contained in [revisions] and in [entriesHashList])
* - the previous block hash
*
* If any of the computed hashes of user information cannot be validated or any of the system
* hashes do not result in the correct computed values, this method will throw an IllegalArgumentException.
*
* Internal-only system metadata is represented by its hash, and can be present in the form of certain
* items in the [revisions] list that only contain a hash and no user data, as well as some hashes
* in [entriesHashList].
*
* To validate that the hashes of the user data are valid components of the [blockHash], this method
* performs the following steps:
*
* 1. Compute the hash of the [transactionInfo] and validate that it is included in the [entriesHashList].
* 2. Compute the hash of the [redactionInfo], if present, and validate that it is included in the [entriesHashList].
* 3. Validate the hash of each user revision was correctly computed and matches the hash published
* with that revision.
* 4. Compute the hash of the [revisions] by treating the revision hashes as the leaf nodes of a Merkle tree
* and calculating the root hash of that tree. Then validate that hash is included in the [entriesHashList].
* 5. Compute the hash of the [entriesHashList] by treating the hashes as the leaf nodes of a Merkle tree
* and calculating the root hash of that tree. Then validate that hash matches [entriesHash].
* 6. Finally, compute the block hash by computing the hash resulting from concatenating the [entriesHash]
* and previous block hash, and validate that the result matches the [blockHash] provided by QLDB with the block.
*
* This method is called by ValidateQldbHashChain::verify for each journal block to validate its
* contents before verifying that the hash chain between consecutive blocks is correct.
*/
public void verifyBlockHash() {
Set entriesHashSet = new HashSet<>();
Arrays.stream(entriesHashList).forEach(hash -> entriesHashSet.add(wrap(hash).asReadOnlyBuffer()));
byte[] computedTransactionInfoHash = computeTransactionInfoHash();
if (!entriesHashSet.contains(wrap(computedTransactionInfoHash).asReadOnlyBuffer())) {
throw new IllegalArgumentException(
"Block transactionInfo hash is not contained in the QLDB block entries hash list.");
}
if (redactionInfo != null) {
byte[] computedRedactionInfoHash = computeRedactionInfoHash();
if (!entriesHashSet.contains(wrap(computedRedactionInfoHash).asReadOnlyBuffer())) {
throw new IllegalArgumentException(
"Block redactionInfo hash is not contained in the QLDB block entries hash list.");
}
}
if (revisions != null) {
revisions.forEach(QldbRevision::verifyRevisionHash);
byte[] computedRevisionsHash = computeRevisionsHash();
if (!entriesHashSet.contains(wrap(computedRevisionsHash).asReadOnlyBuffer())) {
throw new IllegalArgumentException(
"Block revisions list hash is not contained in the QLDB block entries hash list.");
}
}
byte[] computedEntriesHash = computeEntriesHash();
if (!Arrays.equals(computedEntriesHash, entriesHash)) {
throw new IllegalArgumentException("Computed entries hash does not match entries hash provided in the block.");
}
byte[] computedBlockHash = Verifier.dot(computedEntriesHash, previousBlockHash);
if (!Arrays.equals(computedBlockHash, blockHash)) {
throw new IllegalArgumentException("Computed block hash does not match block hash provided in the block.");
}
}
private byte[] computeTransactionInfoHash() {
try {
return QldbIonUtils.hashIonValue(Constants.MAPPER.writeValueAsIonValue(transactionInfo));
} catch (IOException e) {
throw new IllegalArgumentException("Could not compute transactionInfo hash to verify block hash.", e);
}
}
private byte[] computeRedactionInfoHash() {
try {
return QldbIonUtils.hashIonValue(Constants.MAPPER.writeValueAsIonValue(redactionInfo));
} catch (IOException e) {
throw new IllegalArgumentException("Could not compute redactionInfo hash to verify block hash.", e);
}
}
private byte[] computeRevisionsHash() {
return Verifier.calculateMerkleTreeRootHash(revisions.stream().map(QldbRevision::getHash).collect(Collectors.toList()));
}
private byte[] computeEntriesHash() {
return Verifier.calculateMerkleTreeRootHash(Arrays.asList(entriesHashList));
}
}
```
1. 以下のプログラム (`ValidateQldbHashChain.java`) をコンパイルして実行し、次のステップを実行します。
1. 台`vehicle-registration`帳から という名前の Amazon S3 バケットにジャーナルブロックをエクスポートします **qldb-tutorial-journal-export-*111122223333*** ( を自分の AWS アカウント 番号に置き換えます）。
1. `verifyBlockHash()` を呼び出して、各ブロック内の個々のハッシュコンポーネントを検証します。
1. ジャーナルブロック間のハッシュチェーンを検証します。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.services.qldb.model.ExportJournalToS3Result;
import com.amazonaws.services.qldb.model.S3EncryptionConfiguration;
import com.amazonaws.services.qldb.model.S3ObjectEncryptionType;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import java.time.Instant;
import java.util.Arrays;
import java.util.List;
import com.amazonaws.services.securitytoken.AWSSecurityTokenServiceClientBuilder;
import com.amazonaws.services.securitytoken.model.GetCallerIdentityRequest;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.qldb.tutorial.qldb.JournalBlock;
/**
* Validate the hash chain of a QLDB ledger by stepping through its S3 export.
*
* This code accepts an exportId as an argument, if exportId is passed the code
* will use that or request QLDB to generate a new export to perform QLDB hash
* chain validation.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class ValidateQldbHashChain {
public static final Logger log = LoggerFactory.getLogger(ValidateQldbHashChain.class);
private static final int TIME_SKEW = 20;
private ValidateQldbHashChain() { }
/**
* Export journal contents to a S3 bucket.
*
* @return the ExportId of the journal export.
* @throws InterruptedException if the thread is interrupted while waiting for export to complete.
*/
private static String createExport() throws InterruptedException {
String accountId = AWSSecurityTokenServiceClientBuilder.defaultClient()
.getCallerIdentity(new GetCallerIdentityRequest()).getAccount();
String bucketName = Constants.JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX + "-" + accountId;
String prefix = Constants.LEDGER_NAME + "-" + Instant.now().getEpochSecond() + "/";
S3EncryptionConfiguration encryptionConfiguration = new S3EncryptionConfiguration()
.withObjectEncryptionType(S3ObjectEncryptionType.SSE_S3);
ExportJournalToS3Result exportJournalToS3Result =
ExportJournal.createJournalExportAndAwaitCompletion(Constants.LEDGER_NAME,
bucketName, prefix, null, encryptionConfiguration, ExportJournal.DEFAULT_EXPORT_TIMEOUT_MS);
return exportJournalToS3Result.getExportId();
}
/**
* Validates that the chain hash on the {@link JournalBlock} is valid.
*
* @param journalBlocks
* {@link JournalBlock} containing hashes to validate.
* @throws IllegalStateException if previous block hash does not match.
*/
public static void verify(final List journalBlocks) {
if (journalBlocks.size() == 0) {
return;
}
journalBlocks.stream().reduce(null, (previousJournalBlock, journalBlock) -> {
journalBlock.verifyBlockHash();
if (previousJournalBlock == null) { return journalBlock; }
if (!Arrays.equals(previousJournalBlock.getBlockHash(), journalBlock.getPreviousBlockHash())) {
throw new IllegalStateException("Previous block hash doesn't match.");
}
byte[] blockHash = Verifier.dot(journalBlock.getEntriesHash(), previousJournalBlock.getBlockHash());
if (!Arrays.equals(blockHash, journalBlock.getBlockHash())) {
throw new IllegalStateException("Block hash doesn't match entriesHash dot previousBlockHash, the chain is "
+ "broken.");
}
return journalBlock;
});
}
public static void main(final String... args) throws InterruptedException {
try {
String exportId;
if (args.length == 1) {
exportId = args[0];
log.info("Validating QLDB hash chain for exportId: " + exportId);
} else {
log.info("Requesting QLDB to create an export.");
exportId = createExport();
}
List journalBlocks =
JournalS3ExportReader.readExport(DescribeJournalExport.describeExport(Constants.LEDGER_NAME,
exportId), AmazonS3ClientBuilder.defaultClient());
verify(journalBlocks);
} catch (Exception e) {
log.error("Unable to perform hash chain verification.", e);
throw e;
}
}
}
```
`vehicle-registration` 台帳を使用する必要がなくなった場合は、「[ステップ 9 (オプション): リソースをクリーンアップする](getting-started.java.step-9.md)」に進みます。
# ステップ 9 (オプション): リソースをクリーンアップする
**重要**
サポート終了通知: 既存のお客様は、07/31/2025 のサポート終了まで Amazon QLDB を使用できます。詳細については、[「Amazon QLDB 台帳を Amazon Aurora PostgreSQL に移行する](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/)」を参照してください。
`vehicle-registration` 台帳は引き続き使用できます。ただし、不要になった場合は、削除することをお勧めします。
**台帳を削除するには**
1. 次のプログラム (`DeleteLedger.java`) をコンパイルし実行して、`vehicle-registration` 台帳とその内容のすべてを削除します。
```
/*
* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: MIT-0
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package software.amazon.qldb.tutorial;
import com.amazonaws.services.qldb.AmazonQLDB;
import com.amazonaws.services.qldb.model.DeleteLedgerRequest;
import com.amazonaws.services.qldb.model.DeleteLedgerResult;
import com.amazonaws.services.qldb.model.ResourceNotFoundException;
import com.amazonaws.services.qldb.model.UpdateLedgerRequest;
import com.amazonaws.services.qldb.model.UpdateLedgerResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Delete a ledger.
*
* This code expects that you have AWS credentials setup per:
* http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html
*/
public final class DeleteLedger {
public static final Logger log = LoggerFactory.getLogger(DeleteLedger.class);
public static final Long LEDGER_DELETION_POLL_PERIOD_MS = 20_000L;
public static AmazonQLDB client = CreateLedger.getClient();
private DeleteLedger() { }
public static void main(String... args) throws Exception {
try {
setDeletionProtection(Constants.LEDGER_NAME, false);
delete(Constants.LEDGER_NAME);
waitForDeleted(Constants.LEDGER_NAME);
} catch (Exception e) {
log.error("Unable to delete the ledger.", e);
throw e;
}
}
/**
* Send a request to the QLDB database to delete the specified ledger.
*
* @param ledgerName
* Name of the ledger to be deleted.
* @return DeleteLedgerResult.
*/
public static DeleteLedgerResult delete(final String ledgerName) {
log.info("Attempting to delete the ledger with name: {}...", ledgerName);
DeleteLedgerRequest request = new DeleteLedgerRequest().withName(ledgerName);
DeleteLedgerResult result = client.deleteLedger(request);
log.info("Success.");
return result;
}
/**
* Wait for the ledger to be deleted.
*
* @param ledgerName
* Name of the ledger being deleted.
* @throws InterruptedException if thread is being interrupted.
*/
public static void waitForDeleted(final String ledgerName) throws InterruptedException {
log.info("Waiting for the ledger to be deleted...");
while (true) {
try {
DescribeLedger.describe(ledgerName);
log.info("The ledger is still being deleted. Please wait...");
Thread.sleep(LEDGER_DELETION_POLL_PERIOD_MS);
} catch (ResourceNotFoundException ex) {
log.info("Success. The ledger is deleted.");
break;
}
}
}
public static UpdateLedgerResult setDeletionProtection(String ledgerName, boolean deletionProtection) {
log.info("Let's set deletionProtection to {} for the ledger with name {}", deletionProtection, ledgerName);
UpdateLedgerRequest request = new UpdateLedgerRequest()
.withName(ledgerName)
.withDeletionProtection(deletionProtection);
UpdateLedgerResult result = client.updateLedger(request);
log.info("Success. Ledger updated: {}", result);
return result;
}
}
```
**注記**
台帳に対して削除保護が有効になっている場合は、QLDB API を使用して台帳を削除する前に、まず無効にする必要があります。
1. [前のステップ](getting-started.java.step-8.md)でジャーナルデータをエクスポートした場合、不要になったら Simple Storage Service (Amazon S3) コンソールを使用して S3 バケットを削除します。
[https://console.aws.amazon.com/s3/](https://console.aws.amazon.com/s3/) で Amazon S3 コンソールを開きます。