Do not meter on /uptime

Metering on heartbeat URL will poison the metrics.

Author: BanzaiMan

lib/travis/api/app/middleware/user_agent_tracker.rb

@@ -11,6 +11,10 @@ class UserAgentTracker < Middleware
         "Opera", "Mozilla"
       ]
 
+      PATHS_IGNORED = [
+        '/uptime'
+      ]
+
       attr_reader :metrik_prefix
 
       before do
@@ -22,11 +26,13 @@ class UserAgentTracker < Middleware
       end
 
       before(agent: /^$/) do
+        return if PATHS_IGNORED.include?(request.path)
         ::Metriks.meter("#{metrik_prefix}.user_agent.missing").mark
         halt(400, "error" => "missing User-Agent header") if Travis::Features.feature_active?(:require_user_agent)
       end
 
       before(agent: /^.+$/) do
+        return if PATHS_IGNORED.include?(request.path)
         agent = UserAgent.parse(request.user_agent)
         case agent.browser
         when *WEB_BROWSERS

spec/unit/middleware/user_agent_tracker_spec.rb

@@ -3,16 +3,17 @@
     mock_app do
       use Travis::Api::App::Middleware::UserAgentTracker
       get('/') { 'ok' }
+      get('/uptime') { 'OK' }
     end
   end
 
   def expect_meter(name)
     allow(Metriks).to receive(:meter).with(name).and_return(double("meter", mark: nil))
   end
 
-  def get(env = {})
+  def get(env = {}, path = '/')
     env['HTTP_USER_AGENT'] ||= agent if agent
-    super('/', {}, env)
+    super(path, {}, env)
   end
 
   context 'missing User-Agent' do
@@ -99,4 +100,12 @@ def get(env = {})
       get
     end
   end
+
+  context 'get /uptime' do
+    let(:agent) { 'Travis/1.6.8 (Mac OS X 10.9.2 like Darwin; Ruby 2.1.1p42; RubyGems 2.0.14) Faraday/0.8.9 Typhoeus/0.6.7' }
+    specify do
+      expect(Metriks).to_not receive(:meter)
+      get({}, '/uptime')
+    end
+  end
 end