Merge branch '330894-determine-the-right-file-size-limit-for-highlighting-files' into 'master'

Add an additional metric for determine the right file size limit for highlighting files

See merge request gitlab-org/gitlab!63579

lib/gitlab/highlight.rb

@@ -70,6 +70,8 @@ module Gitlab
     end
 
     def highlight_rich(text, continue: true)
+      add_highlight_attempt_metric
+
       tag = lexer.tag
       tokens = lexer.lex(text, continue: continue)
       Timeout.timeout(timeout_time) { @formatter.format(tokens, context.merge(tag: tag)).html_safe }
@@ -90,12 +92,25 @@ module Gitlab
       Gitlab::DependencyLinker.link(blob_name, text, highlighted_text)
     end
 
+    def add_highlight_attempt_metric
+      return unless Feature.enabled?(:track_highlight_timeouts)
+
+      highlighting_attempt.increment(source: (@language || "undefined"))
+    end
+
     def add_highlight_timeout_metric
       return unless Feature.enabled?(:track_highlight_timeouts)
 
       highlight_timeout.increment(source: Gitlab::Runtime.sidekiq? ? "background" : "foreground")
     end
 
+    def highlighting_attempt
+      @highlight_attempt ||= Gitlab::Metrics.counter(
+        :file_highlighting_attempt,
+        'Counts the times highlighting has been attempted on a file'
+      )
+    end
+
     def highlight_timeout
       @highlight_timeout ||= Gitlab::Metrics.counter(
         :highlight_timeout,

spec/lib/gitlab/highlight_spec.rb

@@ -143,9 +143,21 @@ RSpec.describe Gitlab::Highlight do
     end
 
     describe 'highlight timeouts' do
-      context 'when there is a timeout error while highlighting' do
-        let(:result) { described_class.highlight(file_name, content) }
+      let(:result) { described_class.highlight(file_name, content, language: "ruby") }
+
+      context 'when there is an attempt' do
+        it "increments the attempt counter with a defined language" do
+          expect { result }.to change { highlight_attempt_total("ruby") }
+        end
+
+        it "increments the attempt counter with an undefined language" do
+          expect do
+            described_class.highlight(file_name, content)
+          end.to change { highlight_attempt_total("undefined") }
+        end
+      end
 
+      context 'when there is a timeout error while highlighting' do
         before do
           allow(Timeout).to receive(:timeout).twice.and_raise(Timeout::Error)
           # This is done twice because it's rescued first and then
@@ -177,6 +189,12 @@ RSpec.describe Gitlab::Highlight do
       .get(source: source)
   end
 
+  def highlight_attempt_total(source)
+    Gitlab::Metrics
+      .counter(:file_highlighting_attempt, 'Counts the times highlighting has been attempted on a file')
+      .get(source: source)
+  end
+
   def over_highlight_size_limit(source)
     Gitlab::Metrics
       .counter(:over_highlight_size_limit,