Return serializable hash from a represented serializer

app/serializers/base_serializer.rb

@@ -6,6 +6,7 @@ class BaseSerializer
   def represent(resource, opts = {})
     self.class.entity_class
       .represent(resource, opts.merge(request: @request))
+      .as_json
   end
 
   def self.entity(entity_class)

spec/serializers/analytics_build_serializer_spec.rb

 require 'spec_helper'
 
 describe AnalyticsBuildSerializer do
-  let(:serializer) do
-    described_class
-      .new.represent(resource)
-  end
-
-  let(:json) { serializer.as_json }
   let(:resource) { create(:ci_build) }
 
+  subject { described_class.new.represent(resource) }
+
   context 'when there is a single object provided' do
     it 'contains important elements of analyticsBuild' do
-      expect(json)
+      expect(subject)
         .to include(:name, :branch, :short_sha, :date, :total_time, :url, :author)
     end
   end

spec/serializers/analytics_issue_serializer_spec.rb

 require 'spec_helper'
 
 describe AnalyticsIssueSerializer do
-  let(:serializer) do
+  subject do
     described_class
       .new(project: project, entity: :merge_request)
       .represent(resource)
   end
 
   let(:user) { create(:user) }
-  let(:json) { serializer.as_json }
   let(:project) { create(:project) }
   let(:resource) do
     {
@@ -23,7 +22,7 @@ describe AnalyticsIssueSerializer do
 
   context 'when there is a single object provided' do
     it 'contains important elements of the issue' do
-      expect(json).to include(:title, :iid, :created_at, :total_time, :url, :author)
+      expect(subject).to include(:title, :iid, :created_at, :total_time, :url, :author)
     end
   end
 end

spec/serializers/analytics_merge_request_serializer_spec.rb

 require 'spec_helper'
 
 describe AnalyticsMergeRequestSerializer do
-  let(:serializer) do
+  subject do
     described_class
       .new(project: project, entity: :merge_request)
       .represent(resource)
   end
 
   let(:user) { create(:user) }
-  let(:json) { serializer.as_json }
   let(:project) { create(:project) }
   let(:resource) do
     {
@@ -24,7 +23,7 @@ describe AnalyticsMergeRequestSerializer do
 
   context 'when there is a single object provided' do
     it 'contains important elements of the merge request' do
-      expect(json).to include(:title, :iid, :created_at, :total_time, :url, :author, :state)
+      expect(subject).to include(:title, :iid, :created_at, :total_time, :url, :author, :state)
     end
   end
 end

spec/serializers/analytics_stage_serializer_spec.rb

 require 'spec_helper'
 
 describe AnalyticsStageSerializer do
-  let(:serializer) do
-    described_class
-      .new.represent(resource)
+  subject do
+    described_class.new.represent(resource)
   end
 
-  let(:json) { serializer.as_json }
-  let(:resource) { Gitlab::CycleAnalytics::CodeStage.new(project: double, options: {}) }
+  let(:resource) do
+    Gitlab::CycleAnalytics::CodeStage.new(project: double, options: {})
+  end
 
   before do
     allow_any_instance_of(Gitlab::CycleAnalytics::BaseStage).to receive(:median).and_return(1.12)
@@ -15,10 +15,10 @@ describe AnalyticsStageSerializer do
   end
 
   it 'it generates payload for single object' do
-    expect(json).to be_kind_of Hash
+    expect(subject).to be_kind_of Hash
   end
 
   it 'contains important elements of AnalyticsStage' do
-    expect(json).to include(:title, :description, :value)
+    expect(subject).to include(:title, :description, :value)
   end
 end

spec/serializers/analytics_summary_serializer_spec.rb

 require 'spec_helper'
 
 describe AnalyticsSummarySerializer do
-  let(:serializer) do
-    described_class
-      .new.represent(resource)
+  subject do
+    described_class.new.represent(resource)
   end
 
-  let(:json) { serializer.as_json }
   let(:project) { create(:empty_project) }
   let(:user) { create(:user) }
+
   let(:resource) do
-    Gitlab::CycleAnalytics::Summary::Issue.new(project: double,
-                                               from: 1.day.ago,
-                                               current_user: user)
+    Gitlab::CycleAnalytics::Summary::Issue
+      .new(project: double, from: 1.day.ago, current_user: user)
   end
 
   before do
-    allow_any_instance_of(Gitlab::CycleAnalytics::Summary::Issue).to receive(:value).and_return(1.12)
+    allow_any_instance_of(Gitlab::CycleAnalytics::Summary::Issue)
+      .to receive(:value).and_return(1.12)
   end
 
   it 'it generates payload for single object' do
-    expect(json).to be_kind_of Hash
+    expect(subject).to be_kind_of Hash
   end
 
   it 'contains important elements of AnalyticsStage' do
-    expect(json).to include(:title, :value)
+    expect(subject).to include(:title, :value)
   end
 end

spec/serializers/environment_serializer_spec.rb

 require 'spec_helper'
 
 describe EnvironmentSerializer do
-  let(:serializer) do
+  let(:user) { create(:user) }
+  let(:project) { create(:project) }
+
+  let(:json) do
     described_class
       .new(user: user, project: project)
       .represent(resource)
   end
 
-  let(:json) { serializer.as_json }
-  let(:user) { create(:user) }
-  let(:project) { create(:project) }
-
   context 'when there is a single object provided' do
     before do
       create(:ci_build, :manual, name: 'manual1',

spec/serializers/pipeline_serializer_spec.rb

@@ -7,11 +7,7 @@ describe PipelineSerializer do
     described_class.new(user: user)
   end
 
-  let(:entity) do
-    serializer.represent(resource)
-  end
-
-  subject { entity.as_json }
+  subject { serializer.represent(resource) }
 
   describe '#represent' do
     context 'when used without pagination' do