1 #

     2 # Copyright (c) 2008-2015 Thierry Florac <tflorac AT ulthar.net>

     3 # All Rights Reserved.

     4 #

     5 # This software is subject to the provisions of the Zope Public License,

     6 # Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.

     7 # THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED

     8 # WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

     9 # WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS

    10 # FOR A PARTICULAR PURPOSE.

    11 #

    12 

    13 __docformat__ = 'restructuredtext'

    14 

    15 

    16 # import standard library

    17 

    18 # import interfaces

    19 from persistent.interfaces import IPersistent

    20 from transaction.interfaces import ITransactionManager

    21 from ZODB.interfaces import IConnection

    22 

    23 # import packages

    24 from pyams_utils.adapter import adapter_config

    25 

    26 

    27 @adapter_config(context=IPersistent, provides=IConnection)

    28 def get_connection(obj):

    29     """An adapter which gets a ZODB connection of a persistent object.

    30 

    31     We are assuming the object has a parent if it has been created in

    32     this transaction.

    33 

    34     Raises ValueError if it is impossible to get a connection.

    35     """

    36     cur = obj

    37     while not getattr(cur, '_p_jar', None):

    38         cur = getattr(cur, '__parent__', None)

    39         if cur is None:

    40             return None

    41     return cur._p_jar

    42 

    43 

    44 # IPersistent adapters copied from zc.twist package

    45 # also register this for adapting from IConnection

    46 @adapter_config(context=IPersistent, provides=ITransactionManager)

    47 def get_transaction_manager(obj):

    48     conn = IConnection(obj)  # typically this will be

    49                              # zope.app.keyreference.persistent.connectionOfPersistent

    50     try:

    51         return conn.transaction_manager

    52     except AttributeError:

    53         return conn._txn_mgr

    54         # or else we give up; who knows.  transaction_manager is the more

    55         # recent spelling.