Add fixture guard spec for SQL metric queries

This commit adds a guard spec that compares SQL metric queries to a
fixture file in order to catch any arbitrary changes to the queries.

The fixture file can be regenerated using a rake task.

Timestamps are freezed for and a stable set of Devise omniauth providers
is used to make queries that rely on them deterministic and not change
every time the fixture file is regenerated.

ee/spec/lib/ee/gitlab/usage/service_ping_report_spec.rb

@@ -26,4 +26,65 @@ RSpec.describe Gitlab::Usage::ServicePingReport, :use_clean_rails_memory_store_c
       end
     end
   end
+
+  # The fixture for this spec is generated automatically by
+  #   RAILS_ENV=test bin/rake gitlab:usage_data:generate_sql_metrics_fixture
+  #
+  # Do not edit it manually!
+  describe 'guard SQL queries against arbitrary changes' do
+    # These metrics have SQL queries that rely on particular record IDs in
+    # the database, or are otherwise unreliable.
+    let(:ignored_metric_key_paths) do
+      %w(
+        counts.alert_bot_incident_issues
+        counts.issues_created_gitlab_alerts
+        counts.issues_created_manually_from_alerts
+        counts.service_desk_issues
+        counts_monthly.aggregated_metrics.xmau_plan
+        counts_monthly.aggregated_metrics.xmau_project_management
+        counts_monthly.aggregated_metrics.users_work_items
+        counts_weekly.aggregated_metrics.xmau_plan
+        counts_weekly.aggregated_metrics.xmau_project_management
+        counts_weekly.aggregated_metrics.users_work_items
+        topology.duration_s
+        usage_activity_by_stage_monthly.plan.service_desk_issues
+        usage_activity_by_stage.plan.service_desk_issues
+        uuid
+      ).freeze
+    end
+
+    let(:stored_queries_fixture) do
+      fixture_file('lib/gitlab/usage/sql_metrics_queries.json')
+    end
+
+    let(:stored_queries_hash) do
+      Gitlab::Json.parse(stored_queries_fixture).with_indifferent_access
+    end
+
+    before do
+      stub_usage_data_connections
+      stub_object_store_settings
+      stub_prometheus_queries
+      remove_ignored_metrics!(stored_queries_hash)
+
+      allow(License).to receive(:current).and_return(nil)
+    end
+
+    it 'does not change SQL metric queries' do
+      report = Timecop.freeze(2021, 1, 1) do
+        described_class.for(output: :metrics_queries).with_indifferent_access
+      end
+
+      remove_ignored_metrics!(report)
+
+      expect(report).to eq(stored_queries_hash)
+    end
+
+    def remove_ignored_metrics!(hash)
+      ignored_metric_key_paths.each do |key_path|
+        *keys, last_key = key_path.split('.')
+        keys.inject(hash, :fetch)[last_key] = nil
+      end
+    end
+  end
 end

lib/gitlab/usage_data_queries.rb

@@ -50,7 +50,7 @@ module Gitlab
 
       def alt_usage_data(value = nil, fallback: FALLBACK, &block)
         if block_given?
-          { alt_usage_data_block: block.to_s }
+          { alt_usage_data_block: "non-SQL usage data block" }
         else
           { alt_usage_data_value: value }
         end
@@ -58,9 +58,9 @@ module Gitlab
 
       def redis_usage_data(counter = nil, &block)
         if block_given?
-          { redis_usage_data_block: block.to_s }
+          { redis_usage_data_block: "non-SQL usage data block" }
         elsif counter.present?
-          { redis_usage_data_counter: counter }
+          { redis_usage_data_counter: counter.to_s }
         end
       end
 
@@ -74,6 +74,11 @@ module Gitlab
       def epics_deepest_relationship_level
         { epics_deepest_relationship_level: 0 }
       end
+
+      # Do not include Devise omniauth providers for consistency between local and CI-run specs
+      def auth_providers
+        AuthenticationEvent::STATIC_PROVIDERS
+      end
     end
   end
 end

lib/tasks/gitlab/usage_data.rake

@@ -51,6 +51,15 @@ namespace :gitlab do
       File.write(Gitlab::UsageDataCounters::CiTemplateUniqueCounter::KNOWN_EVENTS_FILE_PATH, banner + YAML.dump(all_includes).gsub(/ *$/m, ''))
     end
 
+    desc 'GitLab | UsageDataMetrics | Generate raw SQL metrics queries fixture for RSpec'
+    task generate_sql_metrics_fixture: :environment do
+      queries = Timecop.freeze(2021, 1, 1) do
+        Gitlab::Usage::ServicePingReport.for(output: :metrics_queries)
+      end
+
+      File.write('spec/fixtures/lib/gitlab/usage/sql_metrics_queries.json', Gitlab::Json.pretty_generate(queries))
+    end
+
     def ci_template_includes_hash(source, template_directory = nil)
       Gitlab::UsageDataCounters::CiTemplateUniqueCounter.ci_templates("lib/gitlab/ci/templates/#{template_directory}").map do |template|
         expanded_template_name = Gitlab::UsageDataCounters::CiTemplateUniqueCounter.expand_template_name("#{template_directory}/#{template}")

spec/lib/gitlab/usage_data_queries_spec.rb

@@ -34,14 +34,14 @@ RSpec.describe Gitlab::UsageDataQueries do
   describe '.redis_usage_data' do
     subject(:redis_usage_data) { described_class.redis_usage_data { 42 } }
 
-    it 'returns a class for redis_usage_data with a counter call' do
+    it 'returns a stringified class for redis_usage_data with a counter call' do
       expect(described_class.redis_usage_data(Gitlab::UsageDataCounters::WikiPageCounter))
-        .to eq(redis_usage_data_counter: Gitlab::UsageDataCounters::WikiPageCounter)
+        .to eq(redis_usage_data_counter: "Gitlab::UsageDataCounters::WikiPageCounter")
     end
 
-    it 'returns a stringified block for redis_usage_data with a block' do
+    it 'returns a placeholder string for redis_usage_data with a block' do
       is_expected.to include(:redis_usage_data_block)
-      expect(redis_usage_data[:redis_usage_data_block]).to start_with('#<Proc:')
+      expect(redis_usage_data[:redis_usage_data_block]).to eq('non-SQL usage data block')
     end
   end
 
@@ -53,8 +53,8 @@ RSpec.describe Gitlab::UsageDataQueries do
         .to eq(alt_usage_data_value: 1)
     end
 
-    it 'returns a stringified block for alt_usage_data with a block' do
-      expect(alt_usage_data[:alt_usage_data_block]).to start_with('#<Proc:')
+    it 'returns a placeholder string for alt_usage_data with a block' do
+      expect(alt_usage_data[:alt_usage_data_block]).to eq('non-SQL usage data block')
     end
   end