Add Travis-API-Version tracking specs

Author: BanzaiMan

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

@@ -18,7 +18,7 @@ class UserAgentTracker < Middleware
       attr_reader :metrik_prefix
 
       before do
-        @metrik_prefix = if version = request.env['HTTP_TRAVIS_API_VERSION']
+        @metrik_prefix = if version = request.env['HTTP_TRAVIS_API_VERSION'].to_s.match(/^\d+(\.\d+)*/)
           "api.v#{version}"
         else
           "api.v2"

spec/unit/middleware/user_agent_tracker_spec.rb

@@ -90,6 +90,18 @@ def get(env = {}, path = '/')
       expect_meter("api.v2.user_agent.script.ruby.travis.version.1.6.8")
       get
     end
+
+    context 'Travis-API-Version header' do
+      specify "with Travis-API-Version: 3" do
+        expect_meter("api.v3.user_agent.script.ruby.travis.version.1.6.8")
+        get('HTTP_TRAVIS_API_VERSION' => '3')
+      end
+
+      specify "with Travis-API-Version: 1.7f" do
+        expect_meter("api.v1.7.user_agent.script.ruby.travis.version.1.6.8")
+        get('HTTP_TRAVIS_API_VERSION' => '1.7')
+      end
+    end
   end
 
   context 'Travis CLI' do