Add external HTTP request within transactions tracking

lib/gitlab/database/transaction/context.rb

@@ -43,6 +43,11 @@ def track_backtrace(backtrace)
           (@context[:backtraces] ||= []).push(cleaned_backtrace)
         end
 
+        def initialize_external_http_tracking
+          @context[:external_http_count_start] = external_http_requests_count_total
+          @context[:external_http_duration_start] = external_http_requests_duration_total
+        end
+
         def duration
           return unless @context[:start_time].present?
 
@@ -61,6 +66,11 @@ def should_log?
           return false if logged_already?
 
           savepoints_threshold_exceeded? || duration_threshold_exceeded?
+
+          ## TODO
+          #
+          # External requests duration / count exceeded
+          #
         end
 
         def commit
@@ -108,6 +118,8 @@ def log(operation)
             savepoints_count: @context[:savepoints].to_i,
             rollbacks_count: @context[:rollbacks].to_i,
             releases_count: @context[:releases].to_i,
+            transaction_external_http_requests_count: external_http_requests_count,
+            transaction_external_http_requests_duration: external_http_requests_duration,
             sql: queries,
             savepoint_backtraces: backtraces
           }
@@ -118,6 +130,22 @@ def log(operation)
         def application_info(attributes)
           Gitlab::AppJsonLogger.info(attributes)
         end
+
+        def external_http_requests_count
+          @requests_count ||= external_http_requests_count_total - @context[:external_http_count_start].to_i
+        end
+
+        def external_http_requests_duration
+          @requests_duration ||= external_http_requests_duration_total - @context[:external_http_duration_start].to_f
+        end
+
+        def external_http_requests_count_total
+          ::Gitlab::Metrics::Subscribers::ExternalHttp.request_count.to_i
+        end
+
+        def external_http_requests_duration_total
+          ::Gitlab::Metrics::Subscribers::ExternalHttp.duration.to_f
+        end
       end
     end
   end

lib/gitlab/database/transaction/observer.rb

@@ -21,6 +21,7 @@ def self.instrument_transactions(cmd, event)
             context.set_start_time
             context.set_depth(0)
             context.track_sql(event.payload[:sql])
+            context.initialize_external_http_tracking
           elsif cmd.start_with?('SAVEPOINT', 'EXCEPTION')
             context.set_depth(manager.open_transactions)
             context.increment_savepoints

spec/lib/gitlab/database/transaction/observer_spec.rb

@@ -25,7 +25,7 @@
           User.first
 
           expect(transaction_context).to be_a(::Gitlab::Database::Transaction::Context)
-          expect(context.keys).to match_array(%i(start_time depth savepoints queries backtraces))
+          expect(context.keys).to match_array(%i(start_time depth savepoints queries backtraces external_http_count_start external_http_duration_start))
           expect(context[:depth]).to eq(2)
           expect(context[:savepoints]).to eq(1)
           expect(context[:queries].length).to eq(1)
@@ -38,6 +38,18 @@
       expect(context[:backtraces].length).to eq(1)
     end
 
+    it 'tracks external requests duration', :request_store do
+      # TODO add tests!
+      ActiveRecord::Base.transaction do
+        ActiveRecord::Base.transaction(requires_new: true) do
+          User.first
+
+          expect(context[:external_http_count_start]).to eq(0)
+          expect(context[:external_http_duration_start]).to eq(0)
+        end
+      end
+    end
+
     describe '.extract_sql_command' do
       using RSpec::Parameterized::TableSyntax