wsgi/__init__.py
author Rémi Cardona <remi.cardona@logilab.fr>
Wed, 19 Nov 2014 12:13:32 +0100
changeset 10090 0aebb1c0f849
parent 9735 b71158815bc8
child 10594 6a55853f14c9
permissions -rw-r--r--
[utils] Add a '_cwtracehtml' GET parameter to trace self._cw.w() calls (closes #4601327) The core of this patch is in UStringIO.write(). When tracing is enabled, write() doesn't just append the 'value' argument to the underlying list. Instead, a stack trace is recorded and a special HTML "source" is formatted. The output with tracing enabled is an HTML page, with the original HTML escaped, and made clickable to show the stack trace when the write() call was done. This allows answering the recurring question: "who wrote this tag here?!"

# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""This package contains all WSGI specific code for cubicweb

NOTE: this package borrows a lot of code to Django
      (http://www.djangoproject.com) and to the wsgiref module
      of the python2.5's stdlib.

WSGI corresponding PEP: http://www.python.org/dev/peps/pep-0333/

"""
__docformat__ = "restructuredtext en"

from email import message, message_from_string
from Cookie import SimpleCookie
from StringIO import StringIO
from cgi import parse_header
from pprint import pformat as _pformat


def pformat(obj):
    """pretty prints `obj` if possible"""
    try:
        return _pformat(obj)
    except Exception:
        return u'<could not parse>'

def normalize_header(header):
    """returns a normalized header name

    >>> normalize_header('User_Agent')
    'User-agent'
    """
    return header.replace('_', '-').capitalize()

def safe_copyfileobj(fsrc, fdst, length=16*1024, size=0):
    """
    THIS COMES FROM DJANGO
    A version of shutil.copyfileobj that will not read more than 'size' bytes.
    This makes it safe from clients sending more than CONTENT_LENGTH bytes of
    data in the body.
    """
    if not size:
        return
    while size > 0:
        buf = fsrc.read(min(length, size))
        if not buf:
            break
        fdst.write(buf)
        size -= len(buf)