view MoinMoin/support/werkzeug/contrib/profiler.py @ 6111:1fdd537e9d83

SubProcess: reimplement exec_cmd subclassing Popen and overriding some methods isn't pretty. the code we have was written for py 2.4 or so and the py 2.7 Popen looked quite different. this way with the timer should be less problematic.
author Thomas Waldmann <tw AT waldmann-edv DOT de>
date Tue, 06 Sep 2016 04:39:28 +0200
parents 9f12f41504fc
children
line wrap: on
line source
# -*- coding: utf-8 -*-
"""
    werkzeug.contrib.profiler
    ~~~~~~~~~~~~~~~~~~~~~~~~~

    This module provides a simple WSGI profiler middleware for finding
    bottlenecks in web application.  It uses the :mod:`profile` or
    :mod:`cProfile` module to do the profiling and writes the stats to the
    stream provided (defaults to stderr).

    Example usage::

        from werkzeug.contrib.profiler import ProfilerMiddleware
        app = ProfilerMiddleware(app)

    :copyright: (c) 2014 by the Werkzeug Team, see AUTHORS for more details.
    :license: BSD, see LICENSE for more details.
"""
import sys
import time
import os.path
try:
    try:
        from cProfile import Profile
    except ImportError:
        from profile import Profile
    from pstats import Stats
    available = True
except ImportError:
    available = False


class MergeStream(object):

    """An object that redirects `write` calls to multiple streams.
    Use this to log to both `sys.stdout` and a file::

        f = open('profiler.log', 'w')
        stream = MergeStream(sys.stdout, f)
        profiler = ProfilerMiddleware(app, stream)
    """

    def __init__(self, *streams):
        if not streams:
            raise TypeError('at least one stream must be given')
        self.streams = streams

    def write(self, data):
        for stream in self.streams:
            stream.write(data)


class ProfilerMiddleware(object):

    """Simple profiler middleware.  Wraps a WSGI application and profiles
    a request.  This intentionally buffers the response so that timings are
    more exact.

    By giving the `profile_dir` argument, pstat.Stats files are saved to that
    directory, one file per request. Without it, a summary is printed to
    `stream` instead.

    For the exact meaning of `sort_by` and `restrictions` consult the
    :mod:`profile` documentation.

    .. versionadded:: 0.9
       Added support for `restrictions` and `profile_dir`.

    :param app: the WSGI application to profile.
    :param stream: the stream for the profiled stats.  defaults to stderr.
    :param sort_by: a tuple of columns to sort the result by.
    :param restrictions: a tuple of profiling strictions, not used if dumping
                         to `profile_dir`.
    :param profile_dir: directory name to save pstat files
    """

    def __init__(self, app, stream=None,
                 sort_by=('time', 'calls'), restrictions=(), profile_dir=None):
        if not available:
            raise RuntimeError('the profiler is not available because '
                               'profile or pstat is not installed.')
        self._app = app
        self._stream = stream or sys.stdout
        self._sort_by = sort_by
        self._restrictions = restrictions
        self._profile_dir = profile_dir

    def __call__(self, environ, start_response):
        response_body = []

        def catching_start_response(status, headers, exc_info=None):
            start_response(status, headers, exc_info)
            return response_body.append

        def runapp():
            appiter = self._app(environ, catching_start_response)
            response_body.extend(appiter)
            if hasattr(appiter, 'close'):
                appiter.close()

        p = Profile()
        start = time.time()
        p.runcall(runapp)
        body = b''.join(response_body)
        elapsed = time.time() - start

        if self._profile_dir is not None:
            prof_filename = os.path.join(self._profile_dir,
                                         '%s.%s.%06dms.%d.prof' % (
                                             environ['REQUEST_METHOD'],
                                             environ.get('PATH_INFO').strip(
                                                 '/').replace('/', '.') or 'root',
                                             elapsed * 1000.0,
                                             time.time()
                                         ))
            p.dump_stats(prof_filename)

        else:
            stats = Stats(p, stream=self._stream)
            stats.sort_stats(*self._sort_by)

            self._stream.write('-' * 80)
            self._stream.write('\nPATH: %r\n' % environ.get('PATH_INFO'))
            stats.print_stats(*self._restrictions)
            self._stream.write('-' * 80 + '\n\n')

        return [body]


def make_action(app_factory, hostname='localhost', port=5000,
                threaded=False, processes=1, stream=None,
                sort_by=('time', 'calls'), restrictions=()):
    """Return a new callback for :mod:`werkzeug.script` that starts a local
    server with the profiler enabled.

    ::

        from werkzeug.contrib import profiler
        action_profile = profiler.make_action(make_app)
    """
    def action(hostname=('h', hostname), port=('p', port),
               threaded=threaded, processes=processes):
        """Start a new development server."""
        from werkzeug.serving import run_simple
        app = ProfilerMiddleware(app_factory(), stream, sort_by, restrictions)
        run_simple(hostname, port, app, False, None, threaded, processes)
    return action