Mutations: create link with graphiql

app/graphql/mutations/base_mutation.rb

@@ -1,8 +1,6 @@
 module Mutations
-  class BaseMutation < GraphQL::Schema::RelayClassicMutation
-    argument_class Types::BaseArgument
-    field_class Types::BaseField
-    input_object_class Types::BaseInputObject
-    object_class Types::BaseObject
+  # This class is used as a parent for all mutations, and it is the place to have common utilities
+  class BaseMutation < GraphQL::Schema::Mutation
+    null false
   end
 end

app/graphql/mutations/create_link.rb

@@ -0,0 +1,17 @@
+module Mutations
+  class CreateLink < BaseMutation
+    # arguments passed to the `resolve` method
+    argument :description, String, required: true
+    argument :url, String, required: true
+
+    # return type from the mutation
+    type Types::LinkType
+
+    def resolve(description: nil, url: nil)
+      Link.create!(
+        description: description,
+        url: url,
+      )
+    end
+  end
+end

app/graphql/types/mutation_type.rb

@@ -1,10 +1,5 @@
 module Types
-  class MutationType < Types::BaseObject
-    # TODO: remove me
-    field :test_field, String, null: false,
-      description: "An example field added by the generator"
-    def test_field
-      "Hello World"
-    end
+  class MutationType < BaseObject
+    field :create_link, mutation: Mutations::CreateLink
   end
 end

test/graphql/mutations/create_link_test.rb

@@ -0,0 +1,18 @@
+require 'test_helper'
+
+class Mutations::CreateLinkTest < ActiveSupport::TestCase
+  def perform(user: nil, **args)
+    Mutations::CreateLink.new(object: nil, field: nil, context: {}).resolve(args)
+  end
+
+  test 'create a new link' do
+    link = perform(
+      url: 'http://example.com',
+      description: 'description',
+    )
+
+    assert link.persisted?
+    assert_equal link.description, 'description'
+    assert_equal link.url, 'http://example.com'
+  end
+end