rename BackgroundMigration to SidekiqMigration

lib/gitlab/metrics/background_transaction.rb

@@ -1,6 +1,6 @@
 module Gitlab
   module Metrics
-    class SidekiqTransaction < Transaction
+    class BackgroundTransaction < Transaction
       def initialize(worker_class)
         super()
         @worker_class = worker_class

lib/gitlab/metrics/sidekiq_middleware.rb

@@ -5,7 +5,7 @@ module Gitlab
     # This middleware is intended to be used as a server-side middleware.
     class SidekiqMiddleware
       def call(worker, message, queue)
-        trans = SidekiqTransaction.new(worker.class)
+        trans = BackgroundTransaction.new(worker.class)
 
         begin
           # Old gitlad-shell messages don't provide enqueued_at/created_at attributes

spec/lib/gitlab/metrics/background_transaction_spec.rb

@@ -0,0 +1,13 @@
+require 'spec_helper'
+
+describe Gitlab::Metrics::BackgroundTransaction do
+  let(:test_worker_class) { double(:class, name: 'TestWorker') }
+
+  subject { described_class.new(test_worker_class) }
+
+  describe '#action' do
+    it 'returns transaction action name' do
+      expect(subject.action).to eq('TestWorker#perform')
+    end
+  end
+end

spec/lib/gitlab/metrics/rack_middleware_spec.rb

@@ -32,7 +32,7 @@ describe Gitlab::Metrics::RackMiddleware do
     let(:transaction) { middleware.transaction_from_env(env) }
 
     it 'returns a Transaction' do
-      expect(transaction).to be_an_instance_of(Gitlab::Metrics::Transaction)
+      expect(transaction).to be_an_instance_of(Gitlab::Metrics::WebTransaction)
     end
 
     it 'stores the request method and URI in the transaction as values' do

spec/lib/gitlab/metrics/sidekiq_middleware_spec.rb

@@ -5,7 +5,7 @@ describe Gitlab::Metrics::SidekiqMiddleware do
   let(:message) { { 'args' => ['test'], 'enqueued_at' => Time.new(2016, 6, 23, 6, 59).to_f } }
 
   def run(worker, message)
-    expect(Gitlab::Metrics::Transaction).to receive(:new)
+    expect(Gitlab::Metrics::BackgroundTransaction).to receive(:new)
       .with(worker.class)
       .and_call_original