"""Profiler tools for CherryPy.
CherryPy users
==============
You can profile any of your pages as follows::
from cherrypy.lib import profiler
class Root:
p = profiler.Profiler("/path/to/profile/dir")
@cherrypy.expose
def index(self):
self.p.run(self._index)
def _index(self):
return "Hello, world!"
cherrypy.tree.mount(Root())
You can also turn on profiling for all requests
using the ``make_app`` function as WSGI middleware.
CherryPy developers
===================
This module can be used whenever you make changes to CherryPy,
to get a quick sanity-check on overall CP performance. Use the
``--profile`` flag when running the test suite. Then, use the ``serve()``
function to browse the results in a web browser. If you run this
module from the command line, it will call ``serve()`` for you.
"""
import io
import os
import os.path
import sys
import warnings
import cherrypy
try:
import profile
import pstats
[docs]
def new_func_strip_path(func_name):
"""Add ``__init__`` modules' parents.
This makes the profiler output more readable.
"""
filename, line, name = func_name
if filename.endswith('__init__.py'):
return (
os.path.basename(filename[:-12]) + filename[-12:],
line,
name,
)
return os.path.basename(filename), line, name
pstats.func_strip_path = new_func_strip_path
except ImportError:
profile = None
pstats = None
_count = 0
[docs]
class Profiler(object):
"""A profiling app."""
def __init__(self, path=None):
"""Prepare the profiling app resources."""
if not path:
path = os.path.join(os.path.dirname(__file__), 'profile')
self.path = path
if not os.path.exists(path):
os.makedirs(path)
[docs]
def run(self, func, *args, **params):
"""Dump profile data into self.path."""
global _count
c = _count = _count + 1
path = os.path.join(self.path, 'cp_%04d.prof' % c)
prof = profile.Profile()
result = prof.runcall(func, *args, **params)
prof.dump_stats(path)
return result
[docs]
def statfiles(self):
"""Compose a list of statistics file names.
:returns: A list of available profiles.
:rtype: list[str]
"""
return [f for f in os.listdir(self.path)
if f.startswith('cp_') and f.endswith('.prof')]
[docs]
def stats(self, filename, sortby='cumulative'):
"""Generate statistics from given profile.
:returns: The sorted stats index printout.
:rtype: str
"""
sio = io.StringIO()
if sys.version_info >= (2, 5):
s = pstats.Stats(os.path.join(self.path, filename), stream=sio)
s.strip_dirs()
s.sort_stats(sortby)
s.print_stats()
else:
# pstats.Stats before Python 2.5 didn't take a 'stream' arg,
# but just printed to stdout. So re-route stdout.
s = pstats.Stats(os.path.join(self.path, filename))
s.strip_dirs()
s.sort_stats(sortby)
oldout = sys.stdout
try:
sys.stdout = sio
s.print_stats()
finally:
sys.stdout = oldout
response = sio.getvalue()
sio.close()
return response
[docs]
@cherrypy.expose
def index(self):
"""Render the profiling viewer index page."""
return """<html>
<head><title>CherryPy profile data</title></head>
<frameset cols='200, 1*'>
<frame src='menu' />
<frame name='main' src='' />
</frameset>
</html>
"""
[docs]
@cherrypy.expose
def report(self, filename):
"""Render a statistics report."""
cherrypy.response.headers['Content-Type'] = 'text/plain'
return self.stats(filename)
[docs]
class ProfileAggregator(Profiler):
"""A profiling aggregator app."""
def __init__(self, path=None):
"""Prepare the profiling aggregator app resources."""
Profiler.__init__(self, path)
global _count
self.count = _count = _count + 1
self.profiler = profile.Profile()
[docs]
def run(self, func, *args, **params):
"""Dump aggeregated profile data into ``self.path``."""
path = os.path.join(self.path, 'cp_%04d.prof' % self.count)
result = self.profiler.runcall(func, *args, **params)
self.profiler.dump_stats(path)
return result
[docs]
class make_app:
"""Profiling WSGI middleware wrapper."""
def __init__(self, nextapp, path=None, aggregate=False):
"""Make a WSGI middleware app which wraps 'nextapp' with profiling.
nextapp
the WSGI application to wrap, usually an instance of
cherrypy.Application.
path
where to dump the profiling output.
aggregate
if True, profile data for all HTTP requests will go in
a single file. If False (the default), each HTTP request will
dump its profile data into a separate file.
"""
if profile is None or pstats is None:
msg = ('Your installation of Python does not have a profile '
"module. If you're on Debian, try "
'`sudo apt-get install python-profiler`. '
'See http://www.cherrypy.org/wiki/ProfilingOnDebian '
'for details.')
warnings.warn(msg)
self.nextapp = nextapp
self.aggregate = aggregate
if aggregate:
self.profiler = ProfileAggregator(path)
else:
self.profiler = Profiler(path)
def __call__(self, environ, start_response):
"""Process a WSGI request."""
def gather():
result = []
for line in self.nextapp(environ, start_response):
result.append(line)
return result
return self.profiler.run(gather)
[docs]
def serve(path=None, port=8080):
"""Serve the web app with profiler activated."""
if profile is None or pstats is None:
msg = ('Your installation of Python does not have a profile module. '
"If you're on Debian, try "
'`sudo apt-get install python-profiler`. '
'See http://www.cherrypy.org/wiki/ProfilingOnDebian '
'for details.')
warnings.warn(msg)
cherrypy.config.update({'server.socket_port': int(port),
'server.thread_pool': 10,
'environment': 'production',
})
cherrypy.quickstart(Profiler(path))
if __name__ == '__main__':
serve(*tuple(sys.argv[1:]))
