GraphQL batchGet returns 'null' from DynamoDB

[mmz15]

This post comes from spending 3 hours with AWS premium support for the past 2 days, in addition to time spent individually debugging. Perhaps I could get some clarity in this forum.

I'm trying to create a GraphQL API that leverages the batchGet functionality. Regardless of configuration, however, I consistently get the following from the AppSync console:

{
  "data": {
    "batchGet": null
  }
}

I'm using this request:

query MyQuery {
  batchGet(ids: ["value5", "value6"]) {
    growth
  }
}

This is my DynamoDB table:

And this is my schema.graphql in React:

type Value @model {
  id: ID!
  result: [[Float]]!
  growth: Float
}

type Query {
  batchGet(ids: [ID]): [Value]
}

I went through the recommended tutorial. Also, I have the proper IAM permissions for batch commands.

Finally, here are the respective request and response mappings, taking from the schema section of the AppSync console:

#set($ids = [])
#foreach($id in ${ctx.args.ids})
    #set($map = {})
    $util.qr($map.put("id", $util.dynamodb.toString($id)))
    $util.qr($ids.add($map))
#end

{
    "version" : "2018-05-29",
    "operation" : "BatchGetItem",
    "tables" : {
        "Value-ctwvdp7ygfhyjhq25uvkfzftfy-devtwo": {
            "keys": $util.toJson($ids),
            "consistentRead": true
        }
    }
}

$util.toJson($ctx.result.data.Value)

After days of trying to solve this, I'm beginning to suspect that it's an AppSync bug rather than an error in my code. That said, hopefully I'll stand corrected.

[kyptov]

Result returns by table name. $util.toJson($ctx.result.data.get("Value-ctwvdp7ygfhyjhq25uvkfzftfy-devtwo"))

P.s. Also I advice to enable debug logging to cloudwatch - it helps a lot