add metrics tagging to the sidekiq middleware

app/workers/update_merge_requests_worker.rb

@@ -2,6 +2,12 @@ class UpdateMergeRequestsWorker
   include Sidekiq::Worker
   include DedicatedSidekiqQueue
 
+  attr_reader :targets # for metrics tags
+
+  def initialize
+    @targets = {}
+  end
+
   def perform(project_id, user_id, oldrev, newrev, ref)
     project = Project.find_by(id: project_id)
     return unless project
@@ -9,6 +15,10 @@ class UpdateMergeRequestsWorker
     user = User.find_by(id: user_id)
     return unless user
 
+    @targets = {
+      project_id: project_id,
+      user_id: user_id
+    }
     MergeRequests::RefreshService.new(project, user).execute(oldrev, newrev, ref)
   end
 end

lib/gitlab/metrics/sidekiq_middleware.rb

@@ -11,6 +11,8 @@ module Gitlab
           # Old gitlad-shell messages don't provide enqueued_at/created_at attributes
           trans.set(:sidekiq_queue_duration, Time.now.to_f - (message['enqueued_at'] || message['created_at'] || 0))
           trans.run { yield }
+
+          worker.targets.each { |name, target| trans.add_tag(name, target) } if worker.respond_to?(:targets)
         rescue Exception => error # rubocop: disable Lint/RescueException
           trans.add_event(:sidekiq_exception)
 

spec/lib/gitlab/metrics/sidekiq_middleware_spec.rb

@@ -4,10 +4,7 @@ describe Gitlab::Metrics::SidekiqMiddleware do
   let(:middleware) { described_class.new }
   let(:message) { { 'args' => ['test'], 'enqueued_at' => Time.new(2016, 6, 23, 6, 59).to_f } }
 
-  describe '#call' do
-    it 'tracks the transaction' do
-      worker = double(:worker, class: double(:class, name: 'TestWorker'))
-
+  def run(worker, message)
     expect(Gitlab::Metrics::Transaction).to receive(:new)
       .with('TestWorker#perform')
       .and_call_original
@@ -20,19 +17,17 @@ describe Gitlab::Metrics::SidekiqMiddleware do
     middleware.call(worker, message, :test) { nil }
   end
 
-    it 'tracks the transaction (for messages without `enqueued_at`)' do
+  describe '#call' do
+    it 'tracks the transaction' do
       worker = double(:worker, class: double(:class, name: 'TestWorker'))
 
-      expect(Gitlab::Metrics::Transaction).to receive(:new)
-        .with('TestWorker#perform')
-        .and_call_original
-
-      expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:set)
-        .with(:sidekiq_queue_duration, instance_of(Float))
+      run(worker, message)
+    end
 
-      expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:finish)
+    it 'tracks the transaction (for messages without `enqueued_at`)' do
+      worker = double(:worker, class: double(:class, name: 'TestWorker'))
 
-      middleware.call(worker, {}, :test) { nil }
+      run(worker, {})
     end
 
     it 'tracks any raised exceptions' do
@@ -50,5 +45,18 @@ describe Gitlab::Metrics::SidekiqMiddleware do
       expect { middleware.call(worker, message, :test) }
         .to raise_error(RuntimeError)
     end
+
+    it 'tags the metrics accordingly' do
+      targets = { one: 1, two: 2 }
+      worker = double(:worker, class: double(:class, name: 'TestWorker'))
+      allow(worker).to receive(:targets).and_return(targets)
+
+      targets.each do |tag, value|
+        expect_any_instance_of(Gitlab::Metrics::Transaction).to receive(:add_tag)
+          .with(tag, value)
+      end
+
+      run(worker, message)
+    end
   end
 end