AppSync BatchGetItem issues

Hello,

I have a fairly simple schema (see below), and I try to use BatchGetItem to retrieve several elements from a table. (query allFeedCurrentSequence below).

After hours of trial, I hardcoded parameters in the resolver to understand the issue. My request template is

{
"version" : "2018-05-29",
"operation" : "BatchGetItem",
"tables" : {
"PipeLineResolverFeedTable": {
"keys" : [
{ "UUID" : {"S" : "UUID6"} }
]
}
}
}

And my response template is

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

Whenever I run this query :
query allFeedCurrentSequence {
allFeedCurrentSequence(UUIDs: ["UUID6", "UUID7"]) {
UUID
currentSequence
}
}

I get the following response :

{
"data": {
"allFeedCurrentSequence": null
},
"errors": [
{
"path": [
"allFeedCurrentSequence",
"tricountUUID"
],
"locations": null,
"message": "Cannot return null for non-nullable type: 'String' within parent 'PipeLineResolverFeed' (/allFeedCurrentSequence/UUID)"
}
]
}

The logs are really helpless I must say...

Any idea would be welcome.

j.

SCHEMA

type Mutation {
addFeedEntry(UUID: String!, content: String!): PipeLineResolverFeedEntry
}

type PipeLineResolverFeed {
UUID: String!
currentSequence: Int
}

type PipeLineResolverFeedEntry {
UUID: String!
id: ID!
sequenceInFeed: Int!
content: String
}

type Query {

allFeedCurrentSequence(UUIDs: \[String]): PipeLineResolverFeed  
  

}

schema {
query: Query
mutation: Mutation
}

Edited by: JonathanFallon on Oct 4, 2019 4:47 AM