pyatspi/base.py

   1 #Copyright (C) 2008 Codethink Ltd
   2
   3 #This library is free software; you can redistribute it and/or
   4 #modify it under the terms of the GNU Lesser General Public
   5 #License version 2 as published by the Free Software Foundation.
   6
   7 #This program is distributed in the hope that it will be useful,
   8 #but WITHOUT ANY WARRANTY; without even the implied warranty of
   9 #MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10 #GNU General Public License for more details.
  11 #You should have received a copy of the GNU Lesser General Public License
  12 #along with this program; if not, write to the Free Software
  13 #Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  14
  15 import dbus
  16 from dbus.proxies import Interface
  17 from dbus.exceptions import *
  18
  19 import interfaces
  20
  21 __all__ = [
  22            "AccessibleObjectNoLongerExists",
  23            "AccessibleObjectNotAvailable",
  24            "Enum",
  25            "BaseProxy",
  26           ]
  27
  28 class AccessibleObjectNoLongerExists(Exception):
  29         pass
  30
  31 class AccessibleObjectNotAvailable(Exception):
  32         pass
  33
  34 #------------------------------------------------------------------------------
  35
  36 class Enum(uint):
  37         def __str__(self):
  38                 return self._enum_lookup[int(self)]
  39
  40 #------------------------------------------------------------------------------
  41
  42
  43 class BaseProxyMeta(type):
  44         def __new__(meta, *args, **kwargs):
  45                 cls = type.__new__(meta, *args, **kwargs)
  46
  47                 queryable_interfaces = {
  48                         'Accessible':interfaces.ATSPI_ACCESSIBLE,
  49                         'Action':interfaces.ATSPI_ACTION,
  50                         'Application':interfaces.ATSPI_APPLICATION,
  51                         'Collection':interfaces.ATSPI_COLLECTION,
  52                         'Component':interfaces.ATSPI_COMPONENT,
  53                         'Desktop':interfaces.ATSPI_DESKTOP,
  54                         'Document':interfaces.ATSPI_DOCUMENT,
  55                         'EditableText':interfaces.ATSPI_EDITABLE_TEXT,
  56                         'Hypertext':interfaces.ATSPI_HYPERTEXT,
  57                         'Hyperlink':interfaces.ATSPI_HYPERLINK,
  58                         'Image':interfaces.ATSPI_IMAGE,
  59                         'Selection':interfaces.ATSPI_SELECTION,
  60                         'StreamableContent':interfaces.ATSPI_STREAMABLE_CONTENT,
  61                         'Table':interfaces.ATSPI_TABLE,
  62                         'Text':interfaces.ATSPI_TEXT,
  63                         'Value':interfaces.ATSPI_VALUE,
  64                 }
  65
  66                 def return_query(interface):
  67                         def new_query(self):
  68                                 return self.queryInterface(interface)
  69                         return new_query
  70
  71                 for interface in queryable_interfaces.keys():
  72                         name = 'query%s' % interface
  73                         setattr(cls, name, return_query(queryable_interfaces[interface]))
  74
  75                 return cls
  76
  77 #------------------------------------------------------------------------------
  78
  79 class BaseProxy(object):
  80         """
  81         The base D-Bus proxy for a remote object that implements one or more
  82         of the AT-SPI interfaces.
  83         """
  84
  85         __metaclass__ = BaseProxyMeta
  86
  87         def __init__(self, app_name, acc_path, cache, interface, dbus_object=None):
  88                 """
  89                 Create a D-Bus Proxy for an ATSPI interface.
  90
  91                 cache - ApplicationCache, where the cached data for the accessible can be obtained.
  92                 app_name - D-Bus bus name of the application this accessible belongs to.
  93                 acc_path - D-Bus object path of the server side accessible object.
  94                 parent - Parent accessible.
  95                 dbus_object(kwarg) - The D-Bus proxy object used by the accessible for D-Bus method calls.
  96                 """
  97                 self._cache = cache
  98                 self._app_name = app_name
  99                 self._acc_path = acc_path
 100                 self._dbus_interface = interface
 101
 102                 if not dbus_object:
 103                         dbus_object = cache.connection.get_object(self._app_name,
 104                                                                   self._acc_path,
 105                                                                   introspect=False)
 106                 self._dbus_object = dbus_object
 107
 108                 self._pgetter = self.get_dbus_method("Get",
 109                                                      dbus_interface="org.freedesktop.DBus.Properties")
 110                 self._psetter = self.get_dbus_method("Set",
 111                                                      dbus_interface="org.freedesktop.DBus.Properties")
 112
 113         def __str__(self):
 114                     try:
 115                               return '[%s | %s]' % (self.getRoleName(), self.name)
 116                     except Exception:
 117                               return '[DEAD]'
 118
 119         def __eq__(self, other):
 120                 if other is None:
 121                         return False
 122                 try:
 123                         if self._app_name == other._app_name and \
 124                            self._acc_path == other._acc_path:
 125                                 return True
 126                         else:
 127                                 return False
 128                 except AttributeError:
 129                         return False
 130
 131         def __ne__(self, other):
 132                 return not self.__eq__(other)
 133
 134         def __hash__(self):
 135                 return hash(self._app_name + self._acc_path)
 136
 137         def get_dbus_method(self, *args, **kwargs):
 138                 method =  self._dbus_object.get_dbus_method(*args, **kwargs)
 139
 140                 def dbus_method_func(*iargs, **ikwargs):
 141                         # TODO Need to throw an AccessibleObjectNoLongerExists exception
 142                         # on D-Bus error of the same type.
 143                         try:
 144                                 return method(*iargs, **ikwargs)
 145                         except UnknownMethodException, e:
 146                                 raise NotImplementedError(e)
 147                         except DBusException, e:
 148                                 raise LookupError(e)
 149
 150                 return dbus_method_func
 151
 152         @property
 153         def cached_data(self):
 154                 try:
 155                         return self._cache.get_cache_data(self._app_name, self._acc_path)
 156                 except KeyError:
 157                         raise AccessibleObjectNoLongerExists, \
 158                                 'Cache data cannot be found for path %s in app %s' % (self._acc_path, self._app_name)
 159
 160         @property
 161         def interfaces(self):
 162                 return self.cached_data.interfaces
 163
 164         def queryInterface(self, interface):
 165                 """
 166                 Gets a different accessible interface for this object
 167                 or raises a NotImplemented error if the given interface
 168                 is not supported.
 169                 """
 170                 if interface in self.interfaces:
 171                         return self._cache.create_accessible(self._app_name,
 172                                                              self._acc_path,
 173                                                              interface,
 174                                                              dbus_object=self._dbus_object)
 175                 else:
 176                         raise NotImplementedError(
 177                                 "%s not supported by accessible object at path %s"
 178                                 % (interface, self._acc_path))
 179
 180 #END----------------------------------------------------------------------------