Example: Container of Items

Creating the Models

First, create the SDL for the first model to be combined

type Ball @createModel(accountRelation: LIST, description: "A ball to display") {
  creator: DID! @accountReference
  red: Int
  green: Int
  blue: Int
  radius: Float
}

You will then save this to a file, such as ball.graphql. You can then add the model and get the id.

composedb composite:create --output ball.json ball.graphql cat ball.json | jq '.models | keys_unsorted[0]'

Now we need a second model that will combine with the first model

type Obstacle @createModel(accountRelation: LIST, description: "An obstacle a ball can collide with") {
  creator: DID! @accountReference
  x: Int
  y: Int
  z: Int
  length: Int
  width: Int
  height: Int
}

Next, we're going to combine the existing models into a new model

type Ball @loadModel(id: "<id of ball>") {
  id: ID!
}

type Obstacle @loadModel(id: "<id of obstacle>"){
  id: ID!
}

type Collision @createModel(accountRelation: LIST, description: "Collision between ball and object") {
  ballID: StreamID! @documentReference(model: "Ball")
  ball: Ball! @relationDocument(property: "ballID")
  obstacleID: StreamID! @documentReference(model: "Obstacle")
  obstacle: Ball! @relationDocument(property: "ballID")
  x: Int
  y: Int
  z: Int
}

Save this to a file and add as above.

We can now merge all of these and deploy them as a composite.

composedb composite:merge ball.json obstacle.json collision.json --output=merged.json composedb composite:deploy merged.json composedb composite:compile merged.json runtime.json

Our composite is now ready to use. We can use it with graphiql

composedb graphql:server --graphiql runtime.json

Inserting Data

We can create an item with mutation

mutation CreateNewBall($i: CreateBallInput!){
  createBall(input: $i){
    document {
      id
      radius
    }
  }
}

and variables

{
  "i": {
    "content": {
      "creator": "<some did key>",
      "radius": 45,
      "red": 10,
      "green": 20,
      "blue": 30
    }
  }
}

We can create a second object with a mutation

mutation CreateNewObstacle($i: CreateObstacleInput!){
  createObstacle(input: $i){
    document {
      id
    }
  }
}

and variables

{
  "i": {
    "content": {
      "creator": "<some did key>"
      "x": 1
      "y": 2
      "z": 3
      "length": 4
      "width": 5
      "height": 6
    }
  }
}

Finally we can define the resultant object from combining items

mutation CreateCollision($i: CreateCollisionInput!){
  createCollision(input: $i){
    document {
      id
    }
  }
}

and variables

{
  "i": {
    "content": {
      "ballID": "<id from ball mutation>",
      "obstacleID": "<id from obstacle mutation>"
    }
  }
}

Query The Data

We can query for the combined item

query {
  collisionIndex(first:5) {
    edges {
      node {
        id
        ball {
          id
          radius
        }
        obstacle {
          id
        }
      }
    }
  }
}