Add GraphQL logging feature flag

lib/gitlab/graphql/query_analyzers/logger_analyzer.rb

@@ -7,7 +7,7 @@ module Gitlab
         # Called before initializing the analyzer.
         # Returns true to run this analyzer, or false to skip it.
         def analyze?(query)
-          true # unless there's some reason why we wouldn't log?
+          Feature.enabled?(:graphql_logging, default_enabled: true)
         end
 
         # Called before the visit.

spec/lib/gitlab/graphql/query_analyzers/logger_analyzer_spec.rb

@@ -3,7 +3,6 @@
 require 'spec_helper'
 
 describe Gitlab::Graphql::QueryAnalyzers::LoggerAnalyzer do
-
   subject { described_class.new }
   let(:query_string) { "abc" }
   let(:provided_variables) { { a: 1, b: 2, c: 3 } }
@@ -22,6 +21,24 @@ describe Gitlab::Graphql::QueryAnalyzers::LoggerAnalyzer do
     allow(Gitlab::Metrics::System).to receive(:monotonic_time).and_return(now)
   end
 
+  describe '#analyze?' do
+    context 'feature flag disabled' do
+      before do
+        stub_feature_flags(graphql_logging: false)
+      end
+
+      specify do
+        expect(subject.analyze?(anything)).to be_falsey
+      end
+    end
+
+    context 'feature flag enabled by default' do
+      specify do
+        expect(subject.analyze?(anything)).to be_truthy
+      end
+    end
+  end
+
   describe '#initial_value' do
     it 'assembles a hash with initial values' do
       query = OpenStruct.new(query_string: query_string, provided_variables: provided_variables)