__init__.py
author Alexandre Fayolle <alexandre.fayolle@logilab.fr>
Sat, 29 May 2010 09:52:31 +0000
branchstable
changeset 5600 a826996875e7
parent 5451 7b2e9f774028
child 5881 57387070f612
permissions -rw-r--r--
[win32 service] activate logging to the configured file as soon as possible since we don't always have access to the system events of the computer running CW it is important to get as much information as possible in the log file, especially startup failure messages.

# copyright 2003-2010 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/>.
"""CubicWeb is a generic framework to quickly build applications which describes
relations between entitites.

"""
__docformat__ = "restructuredtext en"

# ignore the pygments UserWarnings
import warnings
warnings.filterwarnings('ignore', category=UserWarning,
                        message='.*was already imported',
                        module='.*pygments')


import __builtin__
# '_' is available in builtins to mark internationalized string but should
# not be used to do the actual translation
if not hasattr(__builtin__, '_'):
    __builtin__._ = unicode

CW_SOFTWARE_ROOT = __path__[0]

import sys, os, logging
from StringIO import StringIO

from logilab.common.logging_ext import set_log_methods


if os.environ.get('APYCOT_ROOT'):
    logging.basicConfig(level=logging.CRITICAL)
else:
    logging.basicConfig()

from cubicweb.__pkginfo__ import version as __version__


set_log_methods(sys.modules[__name__], logging.getLogger('cubicweb'))

# make all exceptions accessible from the package
from cubicweb._exceptions import *

# convert eid to the right type, raise ValueError if it's not a valid eid
typed_eid = int


#def log_thread(f, w, a):
#    print f.f_code.co_filename, f.f_code.co_name
#import threading
#threading.settrace(log_thread)

class Binary(StringIO):
    """customize StringIO to make sure we don't use unicode"""
    def __init__(self, buf=''):
        assert isinstance(buf, (str, buffer)), \
               "Binary objects must use raw strings, not %s" % buf.__class__
        StringIO.__init__(self, buf)

    def write(self, data):
        assert isinstance(data, (str, buffer)), \
               "Binary objects must use raw strings, not %s" % data.__class__
        StringIO.write(self, data)

# use this dictionary to rename entity types while keeping bw compat
ETYPE_NAME_MAP = {}

# XXX cubic web cube migration map. See if it's worth keeping this mecanism
#     to help in cube renaming
CW_MIGRATION_MAP = {}

def neg_role(role):
    if role == 'subject':
        return 'object'
    return 'subject'

def role(obj):
    try:
        return obj.role
    except AttributeError:
        return neg_role(obj.target)

def target(obj):
    try:
        return obj.target
    except AttributeError:
        return neg_role(obj.role)


class CubicWebEventManager(object):
    """simple event / callback manager.

    Typical usage to register a callback::

      >>> from cubicweb import CW_EVENT_MANAGER
      >>> CW_EVENT_MANAGER.bind('after-registry-reload', mycallback)

    Typical usage to emit an event::

      >>> from cubicweb import CW_EVENT_MANAGER
      >>> CW_EVENT_MANAGER.emit('after-registry-reload')

    emit() accepts an additional context parameter that will be passed
    to the callback if specified (and only in that case)
    """
    def __init__(self):
        self.callbacks = {}

    def bind(self, event, callback, *args, **kwargs):
        self.callbacks.setdefault(event, []).append( (callback, args, kwargs) )

    def emit(self, event, context=None):
        for callback, args, kwargs in self.callbacks.get(event, ()):
            if context is None:
                callback(*args, **kwargs)
            else:
                callback(context, *args, **kwargs)

CW_EVENT_MANAGER = CubicWebEventManager()

def onevent(event, *args, **kwargs):
    """decorator to ease event / callback binding

    >>> from cubicweb import onevent
    >>> @onevent('before-registry-reload')
    ... def mycallback():
    ...     print 'hello'
    ...
    >>>
    """
    def _decorator(func):
        CW_EVENT_MANAGER.bind(event, func, *args, **kwargs)
        return func
    return _decorator