Add usage pings for merge request creating

Code Review Usage Ping for Create SMAU

app/services/merge_requests/create_service.rb

@@ -27,6 +27,7 @@ module MergeRequests
       issuable.cache_merge_request_closes_issues!(current_user)
       create_pipeline_for(issuable, current_user)
       issuable.update_head_pipeline
+      Gitlab::UsageDataCounters::MergeRequestCounter.count(:create)
 
       super
     end

changelogs/unreleased/id-code-review-smau.yml

+---
+title: Add usage pings for merge request creating
+merge_request: 32059
+author:
+type: added

lib/gitlab/usage_data.rb

@@ -142,7 +142,8 @@ module Gitlab
          Gitlab::UsageDataCounters::SnippetCounter,
          Gitlab::UsageDataCounters::SearchCounter,
          Gitlab::UsageDataCounters::CycleAnalyticsCounter,
-         Gitlab::UsageDataCounters::SourceCodeCounter
+         Gitlab::UsageDataCounters::SourceCodeCounter,
+         Gitlab::UsageDataCounters::MergeRequestCounter
         ]
       end
 

lib/gitlab/usage_data_counters/merge_request_counter.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module UsageDataCounters
+    class MergeRequestCounter < BaseCounter
+      KNOWN_EVENTS = %w[create].freeze
+      PREFIX = 'merge_request'
+    end
+  end
+end

spec/lib/gitlab/usage_data_counters/merge_request_counter_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::UsageDataCounters::MergeRequestCounter do
+  it_behaves_like 'a redis usage counter', 'Merge Request', :create
+
+  it_behaves_like 'a redis usage counter with totals', :merge_request, create: 5
+end

spec/lib/gitlab/usage_data_spec.rb

@@ -69,6 +69,7 @@ describe Gitlab::UsageData do
         snippet_update: a_kind_of(Integer),
         snippet_comment: a_kind_of(Integer),
         merge_request_comment: a_kind_of(Integer),
+        merge_request_create: a_kind_of(Integer),
         commit_comment: a_kind_of(Integer),
         wiki_pages_create: a_kind_of(Integer),
         wiki_pages_update: a_kind_of(Integer),

spec/services/merge_requests/create_service_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-describe MergeRequests::CreateService do
+describe MergeRequests::CreateService, :clean_gitlab_redis_shared_state do
   include ProjectForksHelper
 
   let(:project) { create(:project, :repository) }
@@ -285,6 +285,12 @@ describe MergeRequests::CreateService do
           end
         end
       end
+
+      it 'increments the usage data counter of create event' do
+        counter = Gitlab::UsageDataCounters::MergeRequestCounter
+
+        expect { service.execute }.to change { counter.read(:create) }.by(1)
+      end
     end
 
     it_behaves_like 'new issuable record that supports quick actions' do