GraphQL.md

GraphQL.md

Queries

Basic query

{ 
  status 
}

{ 
  status: 'available' 
}

Nesting

{ 
  hero { 
    name 
    height 
  } 
}

{
  "hero": {
    "name": "Luke Skywalker",
    "height": 1.74
  }
}

Lists

{
  friends {
    name
  }
}

{
  "friends": [
    { "name": "Luke Skywalker" },
    { "name": "Han Solo" },
    { "name": "R2D2" }
  ]
}

GraphQL queries look the same for both single items or lists of items.

Lookups

{
  hero(id: "1000") {
    id
    name
  }
}

{
  "hero": {
    "id": "1000",
    "name": "Luke Skywalker"
  }
}

Aliases

{
  luke: hero(id: "1000") {
    name
  }
  han: hero(id: "1001") {
    name
  }
}

{ 
  "luke": { "name": "Luke Skywalker" }, 
  "han": { "name": "Han Solo" } 
}

Operation names and variables

Query

query FindHero($id: String!) {
  hero(id: $id) {
    name
  }
}

Just to make things less ambiguous. Also, to use variables, you need an operation name.

Variables

{ 
  "id": "1000" 
}

Mutations

Query

{
  createReview($review) {
    id
  }
}

Variables

{
  "review": {
    "stars": 5
  }
}

{ 
  "createReview": { 
    "id": 5291 
  } 
}

Mutations are just fields that do something when queried.

Multiple types

{
  search(q: "john") {
    id
    ... on User {
      name
    }
    ... on Comment {
      body
      author {
        name
      }
    }
  }
}

Great for searching.

Over HTTP

GET

fetch('http://myapi/graphql?query={ me { name } }')

POST

fetch('http://myapi/graphql', {
  body: JSON.stringify({
    query: '...',
    operationName: '...',
    variables: { ... }
  })
})

Schema

Basic schemas

type Query {
  me: User
  users(limit: Int): [User]
}

type User {
  id: ID!
  name: String
}

See: sogko/graphql-shorthand-notation-cheat-sheet

Built in types

Scalar types

| Int | Integer | | Float | Float | | String | String | | Boolean | Boolean | | ID | ID |

Type definitions

| scalar | Scalar type | | type | Object type | | interface | Interface type | | union | Union type | | enum | Enumerable type | | input | Input object type |

Type modifiers

| String | Nullable string | | String! | Required string | | [String] | List of strings | | [String]! | Required list of strings | | [String!]! | Required list of required strings |

Mutations

type Mutation {
  users(params: ListUsersInput) [User]!
}

Interfaces

interface Entity {
  id: ID!
}

type User implements Entity {
  id: ID!
  name: String
}

Enums

enum DIRECTION {
  LEFT
  RIGHT
}

type Root {
  direction: DIRECTION!
}

Unions

type Artist { ··· }
type Album { ··· }

union Result = Artist | Album

type Query {
  search(q: String) [Result]
}