andreas · April 22, 2013 07:14 · Apr 22, 2013
diff --git a/gistfile1.rb b/gistfile1.rb
@@ -0,0 +1,33 @@
+class RBLineProfiler
+  WALL_TIME_LIMIT = 10e3 # ms
+
+  def initialize(app)
+    @app = app
+  end
+
+  def call(env)
+    result = nil
+    profile = lineprof(/./) { result = @app.call(env) }
+
+    profile.each do |file, line_samples|
+      file_lines = nil
+
+      line_samples.each_with_index do |(wall_time, calls), num|
+        if wall_time > WALL_TIME_LIMIT
+          if !file_lines
+            file_lines = File.readlines(file)
+            puts file
+          end
+
+          printf "% 8.1fms |  %s", wall_time/1000.0, file_lines[num-1]
+        end
+      end
+    end
+
+    result
+  end
+end
+
+# Add to config/application.rb
+
+config.middleware.use RBLineProfiler