Mutations

Mutation mengubah data — create, update, delete. Seperti POST/PUT/DELETE di REST. Convention: mutations return objek yang diubah.

Create

mutation {
  createUser(input: {
    name: "Budi Santoso"
    email: "[email protected]"
    age: 28
  }) {
    id
    name
    email
  }
}

# Response
{
  "data": {
    "createUser": {
      "id": "456",
      "name": "Budi Santoso",
      "email": "[email protected]"
    }
  }
}

Update

mutation UpdateUser($id: ID!, $input: UpdateUserInput!) {
  updateUser(id: $id, input: $input) {
    id
    name
    email
  }
}

# Variables
{
  "id": "456",
  "input": { "name": "Budi S." }
}

Delete

mutation {
  deleteUser(id: "456")
}
# Returns: { "data": { "deleteUser": true } }

Mutation Response Pattern

# Return union type untuk success/error
type MutationResponse {
  success: Boolean!
  message: String
  user: User
}

type Mutation {
  createUser(input: CreateUserInput!): MutationResponse!
}

# Response bisa berisi error tanpa HTTP error
{
  "data": {
    "createUser": {
      "success": false,
      "message": "Email sudah terdaftar",
      "user": null
    }
  }
}

Best Practice

• Mutation name = verb + noun: createUser, updatePost, deleteComment
• Always return affected object (biar cache bisa di-update)
• Use input types (bukan banyak arguments)
• Mutations run sequentially (not parallel like queries)