1 files changed, 71 insertions, 0 deletions
diff --git a/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb b/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb
new file mode 100644
index 00000000000..01b55a1667f
--- /dev/null
+++ b/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb
@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Graphql
+    module QueryAnalyzers
+      class LoggerAnalyzer
+        COMPLEXITY_ANALYZER = GraphQL::Analysis::QueryComplexity.new { |query, complexity_value| complexity_value }
+        DEPTH_ANALYZER = GraphQL::Analysis::QueryDepth.new { |query, depth_value| depth_value }
+
+        def analyze?(query)
+          Feature.enabled?(:graphql_logging, default_enabled: true)
+        end
+
+        def initial_value(query)
+          variables = process_variables(query.provided_variables)
+          default_initial_values(query).merge({
+            query_string: query.query_string,
+            variables: variables
+          })
+        rescue => e
+          Gitlab::Sentry.track_exception(e)
+          default_initial_values(query)
+        end
+
+        def call(memo, visit_type, irep_node)
+          memo
+        end
+
+        def final_value(memo)
+          return if memo.nil?
+
+          analyzers = [COMPLEXITY_ANALYZER, DEPTH_ANALYZER]
+          complexity, depth = GraphQL::Analysis.analyze_query(memo[:query], analyzers)
+
+          memo[:depth] = depth
+          memo[:complexity] = complexity
+          memo[:duration] = duration(memo[:time_started]).round(1)
+
+          GraphqlLogger.info(memo.except!(:time_started, :query))
+        rescue => e
+          Gitlab::Sentry.track_exception(e)
+        end
+
+        private
+
+        def process_variables(variables)
+          if variables.respond_to?(:to_s)
+            variables.to_s
+          else
+            variables
+          end
+        end
+
+        def duration(time_started)
+          nanoseconds = Gitlab::Metrics::System.monotonic_time - time_started
+          nanoseconds * 1000000
+        end
+
+        def default_initial_values(query)
+          {
+            time_started: Gitlab::Metrics::System.monotonic_time,
+            query_string: nil,
+            query: query,
+            variables: nil,
+            duration: nil
+          }
+        end
+      end
+    end
+  end
+end