Allow custom DynamoDB mapper with AttributeTransformer

[micw]

In my use-case I need to encrypt all data in DynamoDB. Fortunately there's a ready-to-use tool from AWS that implements encryption using an AttributeTransformer.
A DynamoDBMapper can be constructed with an AttributeTransformer that is used then. Since spring-data-dynamodb can use a user-provided DynamoDBTemplate it'spossible to inject it at this point.
The problem is that DynamoDBTemplate has no way to set DynamoDBTemplate programmatically nor has it a way to pass an AttributeTransformer. I "fix" this by using reflection but that's not how it should work.

[derjust]

Closed as merged

[ryonday]

Is there a chance we can get this ported to the 4.5.x line and a 4.5.1 released? We are on Spring Boot 1.5.9, and therefore have to use 4.5.0 at the moment. I am in need of using AttributeTransformer and would rather not have to resort to reflection.

Thank you!

[derjust]

@gauravbrills yes this is part of the 5.0.x line

[gauravbrills]

Yes found it thanks

[derjust]

v.4.5.1 is right now publishing to Maven Central

[gauravbrills]

@derjust when running the same get the below error I guess cause of the assert for the dynamoDbMapper , do we need the assert if we supplying the dynamodb mapper with the new constructor provided ?

Caused by: java.lang.AssertionError: null
	at org.socialsignin.spring.data.dynamodb.core.DynamoDBTemplate.<init>(DynamoDBTemplate.java:60)
	at org.socialsignin.spring.data.dynamodb.core.DynamoDBTemplate.<init>(DynamoDBTemplate.java:46)
	at com.wellmanage.wfg.fdps.DynamoDBTestConfig.dynamoDbOperations(DynamoDBTestConfig.java:83)

[gauravbrills]

For now created a custom Dynamodbtemplate to solve this and passing it as a dynamodboperationRef .. had to make the following changes to skip the assert check in DynamoDbTemplate

DynamoDBTemplate(AmazonDynamoDB amazonDynamoDB, DynamoDBMapperConfig dynamoDBMapperConfig,
         DynamoDBMapper dynamoDBMapper)
   {
      this.amazonDynamoDB = amazonDynamoDB;
      if (dynamoDBMapper == null && dynamoDBMapperConfig == null)
      {
         this.dynamoDBMapperConfig = DynamoDBMapperConfig.DEFAULT;
         this.dynamoDBMapper = new DynamoDBMapper(amazonDynamoDB);
        // Mapper must be null as it could not have been constructed without a Config
            assert dynamoDBMapper == null;
      }
      else
      {
         this.dynamoDBMapperConfig = dynamoDBMapperConfig;
         if (dynamoDBMapper == null)
         {
            this.dynamoDBMapper = new DynamoDBMapper(amazonDynamoDB, dynamoDBMapperConfig);
         }
         else
         {
            this.dynamoDBMapper = dynamoDBMapper;
         }
      }
   }

do review this , I guess it needs to be changed or will do a PR . For now have created a custom DybamoDbTemplate with the above code to fix the same

[derjust]

#105 cherry-picked & added unit tests (and fixed a typo) 👍

• merged into master as Follup PR to #105 #106
• merged into v4.5.x as Backport PR #105 #107 - released 4.5.2 to Maven Central

Thanks & happy holidays 🎄 @gauravbrills

[gauravbrills]

Great..Happy holidays 🎄 to you too @derjust 😊

[kpcsuh]

In my case I need both Dynamo Table prefix like (DEV_, QA_, etc) and encrypt all data in DynamoDB.
Right now, DynamoDBTemplate constructor takes either DynamoDBMapperConfig or DynamoDBMapper but not both. Any solution for my problem?

I think below constructor should be public as well? I may be wrong.

DynamoDBTemplate(AmazonDynamoDB amazonDynamoDB, DynamoDBMapperConfig dynamoDBMapperConfig, DynamoDBMapper dynamoDBMapper)