AppSync/Amplify - how to define GraphQL subscriptions

Question

I am using Amplify to auto-generate queries, mutations and subscriptions. and I have this type:

type Message @model {  
  id: ID!
  author: User @connection(name: "UserMessages")
  content: String
}

How do I add authorID as a filter to subscriptions for new messages using Amplify generated schema?

Answer 1

You may add your own subscription fields that are parameterized however you like.

Try this

# Add the authorId explicitly and turn off the generated subscriptions.
type Message @model(subscriptions: null) {  
  id: ID!
  author: User @connection(name: "UserMessages")
  authorId: String
  content: String
}
type Subscription {
  onCreateMessage(authorId: String!): Message @aws_subscribe(mutations: "createMessage")
}

Subscribed clients only get messages with the authorId provided in the subscription query:

subscription SubscribeToNewMessages($id: String!) {
  onCreateMessage(authorId: $id) {
    id
    authorId
    content
  }
}