Rails+GraphiQL을 사용하여 API 만들기

각 버전

ruby: 2.7.1
rails: 6.0.3.4
graphql-ruby: 1.11.6

GraphQL Ruby

graphiql-rails

환경 구조

gem 'graphql'
gem 'graphiql-rails' # 今回は先に入れました

$ rails generate graphql:install
      create  app/graphql/types
      create  app/graphql/types/.keep
      create  app/graphql/app_schema.rb
      create  app/graphql/types/base_object.rb
      create  app/graphql/types/base_argument.rb
      create  app/graphql/types/base_field.rb
      create  app/graphql/types/base_enum.rb
      create  app/graphql/types/base_input_object.rb
      create  app/graphql/types/base_interface.rb
      create  app/graphql/types/base_scalar.rb
      create  app/graphql/types/base_union.rb
      create  app/graphql/types/query_type.rb
add_root_type  query
      create  app/graphql/mutations
      create  app/graphql/mutations/.keep
      create  app/graphql/mutations/base_mutation.rb
      create  app/graphql/types/mutation_type.rb
add_root_type  mutation
      create  app/controllers/graphql_controller.rb
       route  post "/graphql", to: "graphql#execute"
     gemfile  graphiql-rails
       route  graphiql-rails

Rails.application.routes.draw do

  # GraphQL
  if Rails.env.development?
    mount GraphiQL::Rails::Engine, at: '/graphiql', graphql_path: '/graphql'
  end

  post '/graphql', to: 'graphql#execute'
end

이루어지다

Query 만들기

create_table :users do |t|
  t.string :name, null: false
  t.string :email
  t.timestamps
end

$ bundle exec rails g graphql:object User id:ID! name:String! email:String

$ bundle exec rails g graphql:object User

module Types
  class UserType < Types::BaseObject
    field :id, ID, null: false
    field :name, String, null: false
    field :email, String, null: true
    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
  end
end

    field :users, [Types::UserType], null: false
    def users
      User.all
    end

{
  users {
    id
    name
    email
  }
}

Mutation 만들기

$ bundle exec rails g graphql:mutation CreateUser

module Mutations
  class CreateUser < BaseMutation
    field :user, Types::UserType, null: true

    argument :name, String, required: true
    argument :email, String, required: false

    def resolve(**args)
      user = User.create!(args)
      {
        user: user
      }
    end
  end
end

module Types
  class MutationType < Types::BaseObject
    field :createUser, mutation: Mutations::CreateUser # 追記
  end
end

mutation {
  createUser(
    input:{
      name: "user"
      email: "[email protected]"
    }
  ){
    user {
      id
      name 
      email
    }
  }
}

Association

module Types
  class LabelType < Types::BaseObject
    field :id, ID, null: false
    field :name, String, null: false
    ...
  end
end

module Types
  class PostType < Types::BaseObject
    field :label, LabelType, null: true
  end
end

{
  posts {
    id
    label {
      id
      name
    }
  }
}

module Types
  class PostType < Types::BaseObject
    field :id, ID, null: false
    field :label, LabelType, null: true
  end
end

module Types
  class UserType < Types::BaseObject
    field :posts, [PostType], null: false
  end
end

{
  user(id: 1234) {
    id
    posts {
      id
      label {
        id
        name
      }
    }
  }
}

graphql-batch

gem 'graphql-batch'

module Loaders
  class RecordLoader < GraphQL::Batch::Loader
    def initialize(model)
      @model = model
    end

    def perform(ids)
      @model.where(id: ids).each { |record| fulfill(record.id, record) }
      ids.each { |id| fulfill(id, nil) unless fulfilled?(id) }
    end
  end
end

module Types
  class PostType < Types::BaseObject
    field :label, LabelType, null: true
    def label
      Loaders::RecordLoader.for(Label).load(object.label_id)
    end
  end
end

module Loaders
  class AssociationLoader < GraphQL::Batch::Loader
    def self.validate(model, association_name)
      new(model, association_name)
      nil
    end

    def initialize(model, association_name)
      @model = model
      @association_name = association_name
      validate
    end

    def load(record)
      raise TypeError, "#{@model} loader can't load association for #{record.class}" unless record.is_a?(@model)
      return Promise.resolve(read_association(record)) if association_loaded?(record)
      super
    end

    # We want to load the associations on all records, even if they have the same id
    def cache_key(record)
      record.object_id
    end

    def perform(records)
      preload_association(records)
      records.each { |record| fulfill(record, read_association(record)) }
    end

    private

    def validate
      unless @model.reflect_on_association(@association_name)
        raise ArgumentError, "No association #{@association_name} on #{@model}"
      end
    end

    def preload_association(records)
      ::ActiveRecord::Associations::Preloader.new.preload(records, @association_name)
    end

    def read_association(record)
      record.public_send(@association_name)
    end

    def association_loaded?(record)
      record.association(@association_name).loaded?
    end
  end
end

module Types
  class UserType < Types::BaseObject
    field :posts, [PostType], null: false
    def posts
      Loaders::AssociationLoader.for(User, :posts).load(object)
    end
  end
end

모드 파일에서 문서 생성

gem 'graphdoc-ruby'

RUN set -ex \
    && wget -qO- https://deb.nodesource.com/setup_10.x | bash - \
    && apt-get update \
    && apt-get install -y \
                 ...
                 --no-install-recommends \
    && rm -rf /var/lib/apt/lists/* \
    && npm install -g yarn \
    && npm install -g @2fd/graphdoc # インストールしとく

Rails.application.routes.draw do
  mount GraphdocRuby::Application, at: 'graphdoc'
end

GraphdocRuby.configure do |config|
  config.endpoint = 'http://0.0.0.0:3000/api/v1/graphql'
end

방독 기술

Sprockets::Rails::Helper::AssetNotPrecompiled in GraphiQL::Rails::Editors#show

//= link graphiql/rails/application.css
//= link graphiql/rails/application.js

gem 'sprockets', '~> 3.7.2'  [#1098:  slowdev/knowledge/ios/FirebaseをCarthageで追加する](/posts/1098) 

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