Example code for AppSync Subscriptions

Requirements

• terraform
• AWS account
• AWS CLI configured

Deploy

• terraform init
• terraform apply

Use

Basic filtering

Go to the AWS Management Console and subscribe to new Todo items:

subscription MySubscription {
  newTodo(name: "todo1") {
    checked
    created
    name
    id
  }
}

On a separate tab, create a new Todo:

mutation MyMutation {
  addTodo(name: "todo1", userId: "user1") {
    id
    name
    created
    checked
  }
}

There is an event on the first tab. Try again with a different name:

mutation MyMutation {
  addTodo(name: "todo5", userId: "user1") {
    id
    name
    created
    checked
  }
}

No event this time.

Advanced filtering

Subscribe to the other subscription field:

subscription MySubscription {
  todo(userId: "user1") {
    todo {
      checked
      created
      id
      name
    }
  }
}

Create a Todo item:

mutation MyMutation {
  addTodo(name: "todo5", userId: "user1") {
    id
  }
}

There is an event. Notice that the Mutation has fewer fields than the Subscription.

Cleanup

• terraform destroy