Avoid race condition when expiring artifacts

app/workers/expire_build_instance_artifacts_worker.rb

@@ -2,10 +2,14 @@ class ExpireBuildInstanceArtifactsWorker
   include Sidekiq::Worker
 
   def perform(build_id)
-    build = Ci::Build.with_expired_artifacts.reorder(nil).find_by(id: build_id)
-    return unless build
+    build = Ci::Build
+      .with_expired_artifacts
+      .reorder(nil)
+      .find_by(id: build_id)
 
-    Rails.logger.info "Removing artifacts build #{build.id}..."
+    return unless build.try(:project)
+
+    Rails.logger.info "Removing artifacts for build #{build.id}..."
     build.erase_artifacts!
   end
 end

spec/workers/expire_build_instance_artifacts_worker_spec.rb

@@ -6,28 +6,48 @@ describe ExpireBuildInstanceArtifactsWorker do
   let(:worker) { described_class.new }
 
   describe '#perform' do
-    before { build }
-
-    subject! { worker.perform(build.id) }
+    before do
+      worker.perform(build.id)
+    end
 
     context 'with expired artifacts' do
-      let(:build) { create(:ci_build, :artifacts, artifacts_expire_at: Time.now - 7.days) }
+      let(:artifacts_expiry) { { artifacts_expire_at: Time.now - 7.days } }
 
-      it 'does expire' do
-        expect(build.reload.artifacts_expired?).to be_truthy
-      end
+      context 'when associated project is valid' do
+        let(:build) do
+          create(:ci_build, :artifacts, artifacts_expiry)
+        end
 
-      it 'does remove files' do
-        expect(build.reload.artifacts_file.exists?).to be_falsey
+        it 'does expire' do
+          expect(build.reload.artifacts_expired?).to be_truthy
+        end
+
+        it 'does remove files' do
+          expect(build.reload.artifacts_file.exists?).to be_falsey
+        end
+
+        it 'does nullify artifacts_file column' do
+          expect(build.reload.artifacts_file_identifier).to be_nil
+        end
       end
 
-      it 'does nullify artifacts_file column' do
-        expect(build.reload.artifacts_file_identifier).to be_nil
+      context 'when associated project was removed' do
+        let(:build) do
+          create(:ci_build, :artifacts, artifacts_expiry) do |build|
+            build.project.delete
+          end
+        end
+
+        it 'does not remove artifacts' do
+          expect(build.reload.artifacts_file.exists?).to be_truthy
+        end
       end
     end
 
     context 'with not yet expired artifacts' do
-      let(:build) { create(:ci_build, :artifacts, artifacts_expire_at: Time.now + 7.days) }
+      let(:build) do
+        create(:ci_build, :artifacts, artifacts_expire_at: Time.now + 7.days)
+      end
 
       it 'does not expire' do
         expect(build.reload.artifacts_expired?).to be_falsey