1 files changed, 90 insertions, 19 deletions
diff --git a/spec/lib/gitlab/optimistic_locking_spec.rb b/spec/lib/gitlab/optimistic_locking_spec.rb
index 0862a9c880e..1d669573b74 100644
--- a/spec/lib/gitlab/optimistic_locking_spec.rb
+++ b/spec/lib/gitlab/optimistic_locking_spec.rb
@@ -5,37 +5,108 @@ require 'spec_helper'
 RSpec.describe Gitlab::OptimisticLocking do
   let!(:pipeline) { create(:ci_pipeline) }
   let!(:pipeline2) { Ci::Pipeline.find(pipeline.id) }
+  let(:histogram) { spy('prometheus metric') }
+
+  before do
+    allow(described_class)
+      .to receive(:retry_lock_histogram)
+      .and_return(histogram)
+  end
 
   describe '#retry_lock' do
-    it 'does not reload object if state changes' do
-      expect(pipeline).not_to receive(:reset)
-      expect(pipeline).to receive(:succeed).and_call_original
+    let(:name) { 'optimistic_locking_spec' }
 
-      described_class.retry_lock(pipeline) do |subject|
-        subject.succeed
+    context 'when state changed successfully without retries' do
+      subject do
+        described_class.retry_lock(pipeline, name: name) do |lock_subject|
+          lock_subject.succeed
+        end
       end
-    end
 
-    it 'retries action if exception is raised' do
-      pipeline.succeed
+      it 'does not reload object' do
+        expect(pipeline).not_to receive(:reset)
+        expect(pipeline).to receive(:succeed).and_call_original
+
+        subject
+      end
+
+      it 'does not create log record' do
+        expect(described_class.retry_lock_logger).not_to receive(:info)
+
+        subject
+      end
 
-      expect(pipeline2).to receive(:reset).and_call_original
-      expect(pipeline2).to receive(:drop).twice.and_call_original
+      it 'adds number of retries to histogram' do
+        subject
 
-      described_class.retry_lock(pipeline2) do |subject|
-        subject.drop
+        expect(histogram).to have_received(:observe).with({}, 0)
       end
     end
 
-    it 'raises exception when too many retries' do
-      expect(pipeline).to receive(:drop).twice.and_call_original
+    context 'when at least one retry happened, the change succeeded' do
+      subject do
+        described_class.retry_lock(pipeline2, name: 'optimistic_locking_spec') do |lock_subject|
+          lock_subject.drop
+        end
+      end
+
+      before do
+        pipeline.succeed
+      end
+
+      it 'completes the action' do
+        expect(pipeline2).to receive(:reset).and_call_original
+        expect(pipeline2).to receive(:drop).twice.and_call_original
+
+        subject
+      end
+
+      it 'creates a single log record' do
+        expect(described_class.retry_lock_logger)
+          .to receive(:info)
+          .once
+          .with(hash_including(:time_s, name: name, retries: 1))
 
-      expect do
-        described_class.retry_lock(pipeline, 1) do |subject|
-          subject.lock_version = 100
-          subject.drop
+        subject
+      end
+
+      it 'adds number of retries to histogram' do
+        subject
+
+        expect(histogram).to have_received(:observe).with({}, 1)
+      end
+    end
+
+    context 'when MAX_RETRIES attempts exceeded' do
+      subject do
+        described_class.retry_lock(pipeline, max_retries, name: name) do |lock_subject|
+          lock_subject.lock_version = 100
+          lock_subject.drop
         end
-      end.to raise_error(ActiveRecord::StaleObjectError)
+      end
+
+      let(:max_retries) { 2 }
+
+      it 'raises an exception' do
+        expect(pipeline).to receive(:drop).exactly(max_retries + 1).times.and_call_original
+
+        expect { subject }.to raise_error(ActiveRecord::StaleObjectError)
+      end
+
+      it 'creates a single log record' do
+        expect(described_class.retry_lock_logger)
+          .to receive(:info)
+          .once
+          .with(hash_including(:time_s, name: name, retries: max_retries))
+
+        expect { subject }.to raise_error(ActiveRecord::StaleObjectError)
+      end
+
+      it 'adds number of retries to histogram' do
+        expect { subject }.to raise_error(ActiveRecord::StaleObjectError)
+
+        expect(histogram).to have_received(:observe).with({}, max_retries)
+      end
     end
   end