Restructure complexity analyzer

Remove instance variables for class re-use, test individual methods,
use `monotonic_time`

1 files changed, 24 insertions, 16 deletions

diff --git a/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb b/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb
index 3796eefd608..2cebd739a4e 100644
--- a/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb
+++ b/lib/gitlab/graphql/query_analyzers/logger_analyzer.rb
@@ -4,10 +4,6 @@ module Gitlab
   module Graphql
     module QueryAnalyzers
       class LoggerAnalyzer
-        def initialize
-          @info_hash = {}
-        end
-
         # Called before initializing the analyzer.
         # Returns true to run this analyzer, or false to skip it.
         def analyze?(query)
@@ -18,16 +14,20 @@ module Gitlab
         # Returns the initial value for `memo`
         def initial_value(query)
           {
-            time_started: Time.zone.now,
+            time_started: Gitlab::Metrics::System.monotonic_time,
             query_string: query.query_string,
-            variables: query.provided_variables
+            variables: process_variables(query.provided_variables),
+            complexity: nil,
+            depth: nil,
+            duration: nil
           }
         end
 
         # This is like the `reduce` callback.
         # The return value is passed to the next call as `memo`
         def call(memo, visit_type, irep_node)
-          memo
+          memo = set_complexity(memo)
+          set_depth(memo)
         end
 
         # Called when we're done the whole visit.
@@ -35,29 +35,37 @@ module Gitlab
         # Or, you can use this hook to write to a log, etc
         def final_value(memo)
           memo[:duration] = "#{duration(memo[:time_started]).round(1)}ms"
-          set_complexity
-          set_depth
-          GraphqlLogger.info(memo.except!(:time_started).merge(@info_hash))
+          GraphqlLogger.info(memo.except!(:time_started))
           memo
         end
 
         private
 
-        def set_complexity
+        def process_variables(variables)
+          if variables.respond_to?(:to_unsafe_h)
+            variables.to_unsafe_h
+          else
+            variables
+          end
+        end
+
+        def set_complexity(memo)
           GraphQL::Analysis::QueryComplexity.new do |query, complexity_value|
-            @info_hash[:complexity] = complexity_value
+            memo[:complexity] = complexity_value
           end
+          memo
         end
 
-        def set_depth
+        def set_depth(memo)
           GraphQL::Analysis::QueryDepth.new do |query, depth_value|
-            @info_hash[:depth] = depth_value
+            memo[:depth] = depth_value
           end
+          memo
         end
 
         def duration(time_started)
-          nanoseconds = Time.zone.now - time_started
-          nanoseconds / 1000000
+          nanoseconds = Gitlab::Metrics::System.monotonic_time - time_started
+          nanoseconds * 1000000
         end
       end
     end