Add abstract route to span name openzipkin#96

lib/zipkin-tracer/application.rb

@@ -11,6 +11,17 @@ def self.routable_request?(path_info, http_method)
       false
     end
 
+    def self.get_route(path_info, http_method)
+      return "" unless defined?(Rails)
+      req = Rack::Request.new("PATH_INFO" => path_info, "REQUEST_METHOD" => http_method)
+      # Returns a string like /some/path/:id
+      Rails.application.routes.router.recognize(req) { |route|
+        return route.path.spec.to_s
+      }
+    rescue
+      ""
+    end
+
     def self.logger
       if defined?(Rails) # If we happen to be inside a Rails app, use its logger
         Rails.logger

lib/zipkin-tracer/rack/zipkin-tracer.rb

@@ -30,7 +30,7 @@ def call(env)
         if !trace_id.sampled? || !routable_request?(env)
           @app.call(env)
         else
-          @tracer.with_new_span(trace_id, env[REQUEST_METHOD].to_s.downcase) do |span|
+          @tracer.with_new_span(trace_id, "#{env[REQUEST_METHOD].to_s.downcase} #{route(env)}".strip) do |span|
             trace!(span, zipkin_env) { @app.call(env) }
           end
         end
@@ -40,7 +40,11 @@ def call(env)
     private
 
     def routable_request?(env)
-      Application.routable_request?(env[PATH_INFO],  env[REQUEST_METHOD])
+      Application.routable_request?(env[PATH_INFO], env[REQUEST_METHOD])
+    end
+
+    def route(env)
+      Application.get_route(env[PATH_INFO], env[REQUEST_METHOD])
     end
 
     def annotate_plugin(span, env, status, response_headers, response_body)

spec/lib/application_spec.rb

@@ -38,6 +38,43 @@ module ZipkinTracer
       end
     end
 
+    describe '.get_route' do
+      subject { Application.get_route("path", "METHOD") }
+
+      context 'Rails available' do
+        before do
+          stub_const('Rails', Class.new)
+        end
+
+        context 'route for /api/v1/messages/123 is found' do
+          before do
+            route = "/api/v1/messages/:id"
+            allow(Rails).to receive_message_chain('application.routes.router.recognize') { route }
+          end
+
+          it 'returns route' do
+            expect(subject).to eq("/api/v1/messages/:id")
+          end
+        end
+
+        context 'route is not found' do
+          before do
+            allow(Rails).to receive_message_chain('application.routes.router.recognize') { nil }
+          end
+
+          it 'returns nil' do
+            expect(subject).to eq(nil)
+          end
+        end
+      end
+
+      context 'Rails not available' do
+        it 'returns empty string' do
+          expect(subject).to eq("")
+        end
+      end
+    end
+
     describe '.logger' do
       subject { Application.logger }