Flamegraph middleware that tracks requests

Flame-Graph-Middleware.py

class FlamegraphMiddleware(object):
    def __init__(self):
        import os, socket, datetime
        arguments = os.getpid(), socket.gethostname()
        filename = '/tmp/flamegraph.%s.%s.log' % arguments

        self.profiler = self.create_profiler(filename)
        print('FlameGraph started: %s' % filename)

    def __del__(self):
        self.profiler.stop()
        self.profiler.join()
        print('FlameGraph finished')

    def create_profiler(self, filename):
        import time
        from flamegraph import flamegraph

        class ProfileThread(flamegraph.ProfileThread):
            u"""
                ProfilerThread that supports pausing.
            """
            @property
            def _keeprunning(self):
                while getattr(self, '__paused', False):
                    time.sleep(0.001)
                return self.__keeprunning

            @_keeprunning.setter
            def _keeprunning(self, value):
                self.__keeprunning = value

            def watch(self):
                self.__paused = True

            def sleep(self):
                self.__paused = False

        flamegraph.ProfileThread = ProfileThread

        return flamegraph.start_profile_thread(fd=open(filename, 'w'))

    def process_request(self, request):
        self.profiler.watch()

    def process_exception(self, request, exception):
        self.profiler.sleep()