# Recording item interaction events with impressions data
<a name="putevents-including-impressions-data"></a>

If you use the [User-Personalization](native-recipe-new-item-USER_PERSONALIZATION.md) recipe or add the IMPRESSIONS field to your schema for a dataset in a Domain dataset group, you can record impressions data in your PutEvents operation. Impressions are lists of items that were visible to a user when they interacted with (for example, clicked or watched) a particular item. Amazon Personalize uses impressions data to guide exploration, where recommendations include items with less interactions data or relevance. For information on the *implicit* and *explicit* impressions Amazon Personalize can model, see [Impressions data](interactions-datasets.md#interactions-impressions-data). 

**Important**  
If you provide conflicting implicit and explicit impression data in your `PutEvents` requests, Amazon Personalize uses the explicit impressions by default.

To record the Amazon Personalize recommendations you show your user as impressions data, include the `recommendationId` in your [PutEvents](API_UBS_PutEvents.md) request and Amazon Personalize derives the implicit impressions based on your recommendation data.

To manually record impressions data for an event, list the impressions in the [PutEvents](API_UBS_PutEvents.md) command's `impression` input parameter. The following code sample shows how to include a `recommendationId` and an `impression` in a PutEvents operation with either the SDK for Python (Boto3) or the SDK for Java 2.x. If you include both, Amazon Personalize uses the explicit impressions by default.

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#### [ SDK for Python (Boto3) ]

```
import boto3

personalize_events = boto3.client(service_name='personalize-events')

personalize_events.put_events(
    trackingId = 'tracking_id',
    userId= 'userId',
    sessionId = 'sessionId',
    eventList = [{
        'eventId': 'event1',
        'eventType': 'rating',
        'sentAt': 1553631760,
        'itemId': 'item id',
        'recommendationId': 'recommendation id',
        'impression': ['itemId1', 'itemId2', 'itemId3']
        }]
)
```

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#### [ SDK for Java 2.x ]

Use the following `putEvents` method to record an event with impressions data and a recommendationId. For the impressions parameter, pass the list of itemIds as an ArrayList.

```
public static void putEvents(PersonalizeEventsClient personalizeEventsClient, 
                                String trackingId, 
                                String sessionId, 
                                String userId, 
                                String eventType, 
                                Float eventValue, 
                                String itemId,
                                ArrayList<String> impressions,
                                String recommendationId) {

    try { 
        Event event = Event.builder()
            .eventType(eventType)
            .sentAt(Instant.ofEpochMilli(System.currentTimeMillis() + 10 * 60 * 1000))
            .itemId(itemId)
            .eventValue(eventValue)
            .impression(impressions)
            .recommendationId(recommendationId)
            .build();

        PutEventsRequest putEventsRequest = PutEventsRequest.builder()
            .trackingId(trackingId)
            .userId(userId)
            .sessionId(sessionId)
            .eventList(event)
            .build();

        int responseCode = personalizeEventsClient.putEvents(putEventsRequest)
            .sdkHttpResponse()
            .statusCode();
        System.out.println("Response code: " + responseCode);

    } catch (PersonalizeEventsException e) {
        System.out.println(e.awsErrorDetails().errorMessage());
    }
}
```

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