How to convert DynamoDBEvent images to DynamoDBv2.Document ?

[Dreamescaper]

I have a lambda subscribed to dynamoDb events. I want to convert event's records to regular JSON, currently we use something like that:

public async Task FunctionHandler(DynamoDBEvent input, ILambdaContext context)
{
        foreach (var record in input.Records)
        {
                var image = record.Dynamodb.NewImage;
                var document = Document.FromAttributeMap(image);
                var json = document.ToJson();
                /*   ....    */
        }
}

However, it doesn't work after the #1648 is merged.
Could anyone suggest what is the easiest way to do same after the update?

[dscpinheiro]

It's related to that change, we'll take a look.

Curious: What are you using the regular JSON for? Are you saving it to a separate DynamoDB table?

[dscpinheiro]

Got it, thanks for the explanation. We missed this use case when doing the major version bump.

I talked to @normj and we should create an alternative ToJson method in the new event class. I'll convert this to an issue so we can better track it.

If you weren't impacted by the IsSet methods in the AttributeValue class (which is the reason we removed the SDK dependency), you should be able to keep using version 2.3.0 of Amazon.Lambda.DynamoDBEvents (there are no other functional differences between that and 3.0.0).

[CriggerMarg]

Can you please post link to the issue here so I can track it too?

[CriggerMarg]

Also, we are simulating dynamo db event in our unit tests and with 3.0.0 we are no longer able to use DynamoDBContext.ToDocument(DTO).ToAttributeMap() method as another AttributeValue class is used in dynamoDbEvent.

[dscpinheiro]

@CriggerMarg The corresponding issue is #1657

[ashovlin]

Replied over on #1657 , but commenting here too that we just released version 3.1.0 which adds ToJson/ToJsonPretty which can be used with DynamoDBEvent. This allows one to convert the event to JSON, which can then be used to convert again to the SDK's document type then an object persistence class.