Send results only for external_pipelines

On GitHub integrations we might have multiple pipelines for the
same SHA. One pipeline triggered by the commit and a different
one from the pull request event. On GitHub, we update the status
of the pull request with the status of the pipeline that finishes
last. This commit cancel sending messages if we also have a
external_pull_request_event pipeline for the same sha.

ee/app/models/project_services/github_service.rb

@@ -68,7 +68,7 @@ class GithubService < Service
   end
 
   def execute(data)
-    return if disabled? || invalid?
+    return if disabled? || invalid? || irrelevant_result?(data)
 
     status_message = StatusMessage.from_pipeline_data(project, self, data)
 
@@ -99,6 +99,31 @@ class GithubService < Service
 
   private
 
+  def irrelevant_result?(data)
+    !external_pull_request_pipeline?(data) &&
+      external_pull_request_pipelines_exist_for_sha?(data)
+  end
+
+  def external_pull_request_pipeline?(data)
+    id = data.dig(:object_attributes, :id)
+
+    external_pull_request_pipelines.id_in(id).exists?
+  end
+
+  def external_pull_request_pipelines_exist_for_sha?(data)
+    sha = data.dig(:object_attributes, :sha)
+
+    return false if sha.nil?
+
+    external_pull_request_pipelines.for_sha(sha).exists?
+  end
+
+  def external_pull_request_pipelines
+    @external_pull_request_pipelines ||= project
+      .ci_pipelines
+      .external_pull_request_event
+  end
+
   def remote_project
     RemoteProject.new(repository_url)
   end

ee/changelogs/unreleased/24089-github-integration-sends-status-from-multiple-pipelines-when-usi.yml

+---
+title: Prefer sending external pull request pipeline statuses over general statuses
+  to GitHub
+merge_request: 20364
+author:
+type: fixed

ee/spec/models/project_services/github_service_spec.rb

@@ -230,6 +230,50 @@ describe GithubService do
       end
     end
 
+    context 'when an external pull request pipeline exists' do
+      let(:external_pr) { create(:external_pull_request, project: project) }
+
+      let!(:external_pipeline) do
+        create(:ci_pipeline,
+          source: :external_pull_request_event,
+          external_pull_request: external_pr,
+          project: project)
+      end
+
+      it 'does not send notification' do
+        expect(subject).not_to receive(:update_status)
+        expect(GithubService::StatusMessage).not_to receive(:from_pipeline_data)
+
+        expect(subject.execute(pipeline_sample_data)).to be_nil
+      end
+
+      it 'sends notification if the sha is not present' do
+        pipeline_sample_data[:object_attributes].delete(:sha)
+
+        expect(subject).to receive(:update_status)
+        expect(GithubService::StatusMessage).to receive(:from_pipeline_data)
+
+        subject.execute(pipeline_sample_data)
+      end
+    end
+
+    context 'when the pipeline is an external pull request pipeline' do
+      let(:external_pr) { create(:external_pull_request, project: project) }
+
+      before do
+        pipeline.update!(
+          source: :external_pull_request_event,
+          external_pull_request: external_pr)
+      end
+
+      it 'sends notification' do
+        expect(subject).to receive(:update_status)
+        expect(GithubService::StatusMessage).to receive(:from_pipeline_data)
+
+        subject.execute(pipeline_sample_data)
+      end
+    end
+
     context 'without a license' do
       it 'does nothing' do
         stub_licensed_features(github_project_service_integration: false)