Mutations

Controlling Mutations

By default, Quail generates create, update, and delete mutations for every resource that declares writable_attributes. You can customize this behavior per resource.

Skipping Mutations

Skip mutations you don’t need:

class ArticleResource
  include Quail::Resource

  attributes :id, :title, :body
  writable_attributes :title, :body

  skip_mutations :delete
end

Overriding Mutations

Override a mutation with your own class:

class ArticleResource
  include Quail::Resource

  attributes :id, :title, :body

  override_mutation :create, CreateArticle
end

app/graphql/mutations/create_article.rb

class CreateArticle < Quail::Mutation
  graphql_name "CreateArticle"

  argument :title, String, required: true
  argument :body, String, required: true

  field :article, ArticleResource.graphql_type, null: true
  field :errors, [String], null: false

  def resolve(title:, body:)
    article = Article.new(title: title, body: body)
    if article.save
      { article: article, errors: [] }
    else
      { article: nil, errors: article.errors.full_messages }
    end
  end
end