From 9e37ff5c8a34db428026fc9e4c56637318b1b7b3 Mon Sep 17 00:00:00 2001
From: Thibaut Courouble <thibaut@me.com>
Date: Sun, 18 Nov 2018 11:29:50 -0500
Subject: [PATCH] Add instrumentation for slow response processing

---
 lib/docs/core/requester.rb                   | 10 +++++++---
 lib/docs/subscribers/requester_subscriber.rb | 13 +++++++++++++
 lib/tasks/docs.thor                          |  2 +-
 3 files changed, 21 insertions(+), 4 deletions(-)
 create mode 100644 lib/docs/subscribers/requester_subscriber.rb

diff --git a/lib/docs/core/requester.rb b/lib/docs/core/requester.rb
index a4657b3a..2e7a8571 100644
--- a/lib/docs/core/requester.rb
+++ b/lib/docs/core/requester.rb
@@ -1,5 +1,7 @@
 module Docs
   class Requester < Typhoeus::Hydra
+    include Instrumentable
+
     attr_reader :request_options
 
     def self.run(urls, options = {}, &block)
@@ -52,9 +54,11 @@ module Docs
     end
 
     def handle_response(response)
-      on_response.each do |callback|
-        result = callback.call(response)
-        result.each { |url| request(url) } if result.is_a? Array
+      instrument 'handle_response.requester', url: response.url do
+        on_response.each do |callback|
+          result = callback.call(response)
+          result.each { |url| request(url) } if result.is_a?(Array)
+        end
       end
     end
   end
diff --git a/lib/docs/subscribers/requester_subscriber.rb b/lib/docs/subscribers/requester_subscriber.rb
new file mode 100644
index 00000000..4629e9f3
--- /dev/null
+++ b/lib/docs/subscribers/requester_subscriber.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Docs
+  class RequesterSubscriber < Subscriber
+    self.namespace = 'requester'
+
+    def handle_response(event)
+      if event.duration > 10_000
+        log "WARN: #{format_url event.payload[:url]} was slow to process (#{(event.duration / 1000).round}s)"
+      end
+    end
+  end
+end
diff --git a/lib/tasks/docs.thor b/lib/tasks/docs.thor
index 7839821e..59fdf9d4 100644
--- a/lib/tasks/docs.thor
+++ b/lib/tasks/docs.thor
@@ -62,7 +62,7 @@ class DocsCLI < Thor
     Docs.rescue_errors = true
     Docs.install_report :store if options[:verbose]
     Docs.install_report :scraper if options[:debug]
-    Docs.install_report :progress_bar, :doc, :image if $stdout.tty?
+    Docs.install_report :progress_bar, :doc, :image, :requester if $stdout.tty?
 
     require 'unix_utils' if options[:package]