Add usage counter for DependencyList

Make DependencyListUsageCounter similar as PodLogsUsageCounter.
Extract similar tests to shared examples.

ee/app/controllers/ee/projects/environments_controller.rb

@@ -15,7 +15,7 @@ module EE
         respond_to do |format|
           format.html
           format.json do
-            ::Gitlab::PodLogsUsageCounter.increment(project.id)
+            ::Gitlab::UsageCounters::PodLogs.increment(project.id)
             ::Gitlab::PollingInterval.set_header(response, interval: 3_000)
 
             render json: {

ee/app/controllers/projects/security/dependencies_controller.rb

@@ -8,6 +8,8 @@ module Projects
       def index
         respond_to do |format|
           format.json do
+            ::Gitlab::UsageCounters::DependencyList.increment(project.id)
+
             render json: ::DependencyListSerializer.new(project: project)
                            .represent(paginated_dependencies, build: build)
           end
@@ -17,7 +19,10 @@ module Projects
       private
 
       def build
-        @build ||= pipeline.builds.latest
+        return unless pipeline
+        return @build if @build
+
+        @build = pipeline.builds.latest
                   .with_reports(::Ci::JobArtifact.dependency_list_reports)
                   .last
       end

ee/changelogs/unreleased/11759-dependency-list-usage-ping.yml

+---
+title: Count usage of DependencyList endpoint
+merge_request: 13962
+author:
+type: added

ee/lib/ee/gitlab/usage_data.rb

@@ -132,7 +132,8 @@ module EE
             projects_with_packages: count(::Packages::Package.select('distinct project_id')),
             projects_with_tracing_enabled: count(ProjectTracingSetting),
             projects_enforcing_code_owner_approval: count(::Project.without_deleted.non_archived.requiring_code_owner_approval),
-            operations_dashboard: operations_dashboard_usage
+            operations_dashboard: operations_dashboard_usage,
+            dependency_list_usages_total: ::Gitlab::UsageCounters::DependencyList.usage_totals[:total]
           }).merge(service_desk_counts).merge(security_products_usage)
 
           # MySql does not support recursive queries so we can't retrieve epics relationship depth
@@ -145,9 +146,9 @@ module EE
 
         override :usage_counters
         def usage_counters
-          super.merge(
-            pod_logs_usages: ::Gitlab::PodLogsUsageCounter.usage_totals
-          )
+          super.merge({
+            pod_logs_usages: ::Gitlab::UsageCounters::PodLogs.usage_totals
+          })
         end
 
         override :jira_usage

ee/lib/gitlab/pod_logs_usage_counter.rb

-# frozen_string_literal: true
-
-module Gitlab
-  module PodLogsUsageCounter
-    BASE_KEY = "POD_LOGS_USAGE_COUNTS"
-
-    class << self
-      def increment(project_id)
-        Gitlab::Redis::SharedState.with { |redis| redis.hincrby(BASE_KEY, project_id, 1) }
-      end
-
-      def usage_totals
-        Gitlab::Redis::SharedState.with do |redis|
-          total_sum = 0
-
-          totals = redis.hgetall(BASE_KEY).each_with_object({}) do |(project_id, count), result|
-            total_sum += result[project_id.to_i] = count.to_i
-          end
-
-          totals[:total] = total_sum
-          totals
-        end
-      end
-    end
-  end
-end

ee/lib/gitlab/usage_counters/common.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module UsageCounters
+    class Common
+      class << self
+        def increment(project_id)
+          Gitlab::Redis::SharedState.with { |redis| redis.hincrby(base_key, project_id, 1) }
+        end
+
+        def usage_totals
+          Gitlab::Redis::SharedState.with do |redis|
+            total_sum = 0
+
+            totals = redis.hgetall(base_key).each_with_object({}) do |(project_id, count), result|
+              total_sum += result[project_id.to_i] = count.to_i
+            end
+
+            totals[:total] = total_sum
+            totals
+          end
+        end
+
+        def base_key
+          raise NotImplementedError
+        end
+      end
+    end
+  end
+end

ee/lib/gitlab/usage_counters/dependency_list.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module UsageCounters
+    class DependencyList < Common
+      def self.base_key
+        'DEPENDENCY_LIST_USAGE_COUNTER'
+      end
+    end
+  end
+end

ee/lib/gitlab/usage_counters/pod_logs.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module UsageCounters
+    class PodLogs < Common
+      def self.base_key
+        'POD_LOGS_USAGE_COUNTS'
+      end
+    end
+  end
+end

ee/spec/controllers/projects/environments_controller_spec.rb

@@ -119,7 +119,7 @@ describe Projects::EnvironmentsController do
       end
 
       it 'registers a usage of the endpoint' do
-        expect(::Gitlab::PodLogsUsageCounter).to receive(:increment).with(project.id)
+        expect(::Gitlab::UsageCounters::PodLogs).to receive(:increment).with(project.id)
 
         get :logs, params: environment_params(pod_name: pod_name, format: :json)
       end

ee/spec/controllers/projects/security/dependencies_controller_spec.rb

@@ -22,6 +22,12 @@ describe Projects::Security::DependenciesController do
           stub_licensed_features(dependency_list: true)
         end
 
+        it 'counts usage of the feature' do
+          expect(::Gitlab::UsageCounters::DependencyList).to receive(:increment).with(project.id)
+
+          get :index, params: params, format: :json
+        end
+
         context 'with existing report' do
           let!(:pipeline) { create(:ee_ci_pipeline, :with_dependency_list_report, project: project) }
 

ee/spec/lib/gitlab/usage_counters/dependency_list_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::UsageCounters::DependencyList, :clean_gitlab_redis_shared_state do
+  it_behaves_like 'a usage counter'
+end

ee/spec/lib/gitlab/usage_counters/pod_logs_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::UsageCounters::PodLogs, :clean_gitlab_redis_shared_state do
+  it_behaves_like 'a usage counter'
+end

ee/spec/lib/gitlab/usage_data_spec.rb

@@ -82,6 +82,7 @@ describe Gitlab::UsageData do
         projects_jira_dvcs_server_active
         feature_flags
         operations_dashboard
+        dependency_list_usages_total
       ))
 
       expect(count_data[:projects_with_prometheus_alerts]).to eq(2)

ee/spec/lib/gitlab/pod_logs_usage_counter_spec.rb → ee/spec/support/shared_examples/lib/gitlab/usage_counters/usage_counter_shared_examples.rb

 # frozen_string_literal: true
 
-require 'spec_helper'
-
-describe Gitlab::PodLogsUsageCounter, :clean_gitlab_redis_shared_state do
+RSpec.shared_examples 'a usage counter' do
   describe '.increment' do
+    let(:project_id) { 12 }
+
     it 'intializes and increments the counter for the project by 1' do
       expect do
-        described_class.increment(12)
-      end.to change { described_class.usage_totals[12] }.from(nil).to(1)
+        described_class.increment(project_id)
+      end.to change { described_class.usage_totals[project_id] }.from(nil).to(1)
     end
   end
 
   describe '.usage_totals' do
+    let(:usage_totals) { described_class.usage_totals }
+
     context 'when the feature has not been used' do
       it 'returns the total counts and counts per project' do
-        expect(described_class.usage_totals.keys).to eq([:total])
-        expect(described_class.usage_totals[:total]).to eq(0)
+        expect(usage_totals.keys).to eq([:total])
+        expect(usage_totals[:total]).to eq(0)
       end
     end
 
     context 'when the feature has been used in multiple projects' do
+      let(:project1_id) { 12 }
+      let(:project2_id) { 16 }
+
       before do
-        described_class.increment(12)
-        described_class.increment(16)
+        described_class.increment(project1_id)
+        described_class.increment(project2_id)
       end
 
       it 'returns the total counts and counts per project' do
-        expect(described_class.usage_totals[12]).to eq(1)
-        expect(described_class.usage_totals[16]).to eq(1)
-        expect(described_class.usage_totals[:total]).to eq(2)
+        expect(usage_totals[project1_id]).to eq(1)
+        expect(usage_totals[project2_id]).to eq(1)
+        expect(usage_totals[:total]).to eq(2)
       end
     end
   end