Expose merge request entity for pipelines

Add preload

Fix

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test only postgresql

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add more test
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Fix

3 files changed, 28 insertions, 0 deletions

diff --git a/app/serializers/merge_request_for_pipeline_entity.rb b/app/serializers/merge_request_for_pipeline_entity.rb
new file mode 100644
index 00000000000..7779ddfd65a
--- /dev/null
+++ b/app/serializers/merge_request_for_pipeline_entity.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class MergeRequestForPipelineEntity < Grape::Entity
+  include RequestAwareEntity
+
+  expose :iid
+
+  expose :path do |merge_request|
+    project_merge_request_path(merge_request.project, merge_request)
+  end
+
+  expose :title
+  expose :source_branch
+  expose :source_branch_path
+  expose :target_branch
+  expose :target_branch_path
+end
diff --git a/app/serializers/pipeline_entity.rb b/app/serializers/pipeline_entity.rb
index c2990cb5159..5ac1e590d39 100644
--- a/app/serializers/pipeline_entity.rb
+++ b/app/serializers/pipeline_entity.rb
@@ -28,6 +28,7 @@ class PipelineEntity < Grape::Entity
     expose :can_retry?, as: :retryable
     expose :can_cancel?, as: :cancelable
     expose :failure_reason?, as: :failure_reason
+    expose :detached_merge_request_pipeline?, as: :detached
   end
 
   expose :details do
@@ -36,6 +37,10 @@ class PipelineEntity < Grape::Entity
     expose :finished_at
   end
 
+  expose :merge_request, if: -> (*) { has_presentable_merge_request? }, with: MergeRequestForPipelineEntity do |pipeline|
+    pipeline.merge_request.present(current_user: request.current_user)
+  end
+
   expose :ref do
     expose :name do |pipeline|
       pipeline.ref
@@ -81,6 +86,11 @@ class PipelineEntity < Grape::Entity
       pipeline.cancelable?
   end
 
+  def has_presentable_merge_request?
+    pipeline.triggered_by_merge_request? &&
+      can?(request.current_user, :read_merge_request, pipeline.merge_request)
+  end
+
   def detailed_status
     pipeline.detailed_status(request.current_user)
   end
diff --git a/app/serializers/pipeline_serializer.rb b/app/serializers/pipeline_serializer.rb
index 7451433a841..dbbeca9431d 100644
--- a/app/serializers/pipeline_serializer.rb
+++ b/app/serializers/pipeline_serializer.rb
@@ -15,6 +15,7 @@ class PipelineSerializer < BaseSerializer
         :manual_actions,
         :scheduled_actions,
         :artifacts,
+        :merge_request,
         {
           pending_builds: :project,
           project: [:route, { namespace: :route }],