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Diffstat (limited to 'python/werkzeug/middleware/profiler.py')
-rw-r--r-- | python/werkzeug/middleware/profiler.py | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/python/werkzeug/middleware/profiler.py b/python/werkzeug/middleware/profiler.py new file mode 100644 index 0000000..32a14d9 --- /dev/null +++ b/python/werkzeug/middleware/profiler.py @@ -0,0 +1,132 @@ +""" +Application Profiler +==================== + +This module provides a middleware that profiles each request with the +:mod:`cProfile` module. This can help identify bottlenecks in your code +that may be slowing down your application. + +.. autoclass:: ProfilerMiddleware + +:copyright: 2007 Pallets +:license: BSD-3-Clause +""" +from __future__ import print_function + +import os.path +import sys +import time +from pstats import Stats + +try: + from cProfile import Profile +except ImportError: + from profile import Profile + + +class ProfilerMiddleware(object): + """Wrap a WSGI application and profile the execution of each + request. Responses are buffered so that timings are more exact. + + If ``stream`` is given, :class:`pstats.Stats` are written to it + after each request. If ``profile_dir`` is given, :mod:`cProfile` + data files are saved to that directory, one file per request. + + The filename can be customized by passing ``filename_format``. If + it is a string, it will be formatted using :meth:`str.format` with + the following fields available: + + - ``{method}`` - The request method; GET, POST, etc. + - ``{path}`` - The request path or 'root' should one not exist. + - ``{elapsed}`` - The elapsed time of the request. + - ``{time}`` - The time of the request. + + If it is a callable, it will be called with the WSGI ``environ`` + dict and should return a filename. + + :param app: The WSGI application to wrap. + :param stream: Write stats to this stream. Disable with ``None``. + :param sort_by: A tuple of columns to sort stats by. See + :meth:`pstats.Stats.sort_stats`. + :param restrictions: A tuple of restrictions to filter stats by. See + :meth:`pstats.Stats.print_stats`. + :param profile_dir: Save profile data files to this directory. + :param filename_format: Format string for profile data file names, + or a callable returning a name. See explanation above. + + .. code-block:: python + + from werkzeug.middleware.profiler import ProfilerMiddleware + app = ProfilerMiddleware(app) + + .. versionchanged:: 0.15 + Stats are written even if ``profile_dir`` is given, and can be + disable by passing ``stream=None``. + + .. versionadded:: 0.15 + Added ``filename_format``. + + .. versionadded:: 0.9 + Added ``restrictions`` and ``profile_dir``. + """ + + def __init__( + self, + app, + stream=sys.stdout, + sort_by=("time", "calls"), + restrictions=(), + profile_dir=None, + filename_format="{method}.{path}.{elapsed:.0f}ms.{time:.0f}.prof", + ): + self._app = app + self._stream = stream + self._sort_by = sort_by + self._restrictions = restrictions + self._profile_dir = profile_dir + self._filename_format = filename_format + + 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(): + app_iter = self._app(environ, catching_start_response) + response_body.extend(app_iter) + + if hasattr(app_iter, "close"): + app_iter.close() + + profile = Profile() + start = time.time() + profile.runcall(runapp) + body = b"".join(response_body) + elapsed = time.time() - start + + if self._profile_dir is not None: + if callable(self._filename_format): + filename = self._filename_format(environ) + else: + filename = self._filename_format.format( + method=environ["REQUEST_METHOD"], + path=( + environ.get("PATH_INFO").strip("/").replace("/", ".") or "root" + ), + elapsed=elapsed * 1000.0, + time=time.time(), + ) + filename = os.path.join(self._profile_dir, filename) + profile.dump_stats(filename) + + if self._stream is not None: + stats = Stats(profile, stream=self._stream) + stats.sort_stats(*self._sort_by) + print("-" * 80, file=self._stream) + print("PATH: {!r}".format(environ.get("PATH_INFO", "")), file=self._stream) + stats.print_stats(*self._restrictions) + print("-" * 80 + "\n", file=self._stream) + + return [body] |