rhodecode.lib.compat

    ~~~~~~~~~~~~~~~~~~~~

    Python backward compatibility functions and common libs

    :created_on: Oct 7, 2011

    :author: marcink

    :copyright: (C) 2009-2010 Marcin Kuzminski <marcin@python-works.com>    

    :license: GPLv3, see COPYING for more details.

"""

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# This program 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 General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

#==============================================================================

# json

#==============================================================================

try:

    import json

except ImportError:

    import simplejson as json

#==============================================================================

# izip_longest

#==============================================================================

try:

    from itertools import izip_longest

except ImportError:

    import itertools

    def izip_longest(*args, **kwds): # noqa

        fillvalue = kwds.get("fillvalue")

        def sentinel(counter=([fillvalue] * (len(args) - 1)).pop):

            yield counter() # yields the fillvalue, or raises IndexError

        fillers = itertools.repeat(fillvalue)

    def as_dict(self):

        return self._dict_impl()(self.items())

    def _repr(self):

        """_repr(): low level repr of the whole data contained in the odict.

        Useful for debugging.

        """

        dict_impl = self._dict_impl()

        form = "odict low level repr lh,lt,data: %r, %r, %s"

        return form % (dict_impl.__getattribute__(self, 'lh'),

                       dict_impl.__getattribute__(self, 'lt'),

                       dict_impl.__repr__(self))

class OrderedDict(_odict, dict):

    def _dict_impl(self):

        return dict

#==============================================================================

# OrderedSet

#==============================================================================

from sqlalchemy.util import OrderedSet

import os

import sys

import time

import errno

from warnings import warn

from multiprocessing.util import Finalize

class LockHeld(Exception):

    pass

class DaemonLock(object):

    """daemon locking

    USAGE:

    try:

        l = DaemonLock(file_='/path/tolockfile',desc='test lock')

        main()

        l.release()

    except LockHeld:

        sys.exit(1)

    """

    def __init__(self, file_=None, callbackfn=None,

                 desc='daemon lock', debug=False):

        self.pidfile = file_ if file_ else os.path.join(

                                                    os.path.dirname(__file__),

                                                    'running.lock')

        self.callbackfn = callbackfn

        self.desc = desc