Is there a good object mapper for Amazons dynamodb(through aws sdk) which can be used in nodejs?

Question

Maybe the question does not apply to dynamoDB due to it not being Relational Db. However, I'm looking for a good object mapper which can be used in nodejs and aws sdk to map existing model classes to dynamoDB tables. Does anyone have experience with this issue/question, or have you used such a module/library?

Answer 1

If you are looking for schema:

• https://github.com/clarkie/dynogels (well supported forked from vogels which has been abandoned)
• https://github.com/automategreen/dynamoose (inspired by Mongoose)

If you are looking for something to throw javascript objects (even circular graphs) to:

• https://github.com/aaaristo/dyngodb (alpha)
• https://github.com/aaaristo/angular-gson-express-dyngodb

dyngodb has experimental support for full-text search, and transactions too.

Both are based on aws-sdk.

Answer 2

Also worth considering is simple marshallers, which just translate between the dynamoDB format and regular js objects or JSON.

DynamoDb-Data-Types
https://github.com/kayomarz/dynamodb-data-types
https://www.npmjs.com/package/dynamodb-data-types

"This utility helps represent AWS DynamoDb data types. It maps (marshalls) JavaScript data into the format required by DynamoDb."

dynamoDb-marshaler
https://github.com/CascadeEnergy/dynamoDb-marshaler https://www.npmjs.com/package/dynamodb-marshaler

"Translates sane javascript objects (and JSON) into DynamoDb format and vice versa." [does not support B type.]

Update 2016-06:
Just discovered that the AWS SDK now does this for you. Their documentation is only partially converted so I guess this is a recent addition. Read about it here.

But these marshallers are still useful because there are circumstances where you can't use the new document client, eg. when processing a dynamoDB stream.