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            "Enum",
  24            "BaseProxy",
  25           ]
  26
  27 class AccessibleObjectNoLongerExists(Exception):
  28         pass
  29
  30 #------------------------------------------------------------------------------
  31
  32 class Enum(int):
  33         def __str__(self):
  34                 return self._enum_lookup[int(self)]
  35
  36 #------------------------------------------------------------------------------
  37
  38
  39 class BaseProxyMeta(type):
  40         def __new__(meta, *args, **kwargs):
  41                 cls = type.__new__(meta, *args, **kwargs)
  42
  43                 queryable_interfaces = {
  44                         'Accessible':interfaces.ATSPI_ACCESSIBLE,
  45                         'Action':interfaces.ATSPI_ACTION,
  46                         'Application':interfaces.ATSPI_APPLICATION,
  47                         'Collection':interfaces.ATSPI_COLLECTION,
  48                         'Component':interfaces.ATSPI_COMPONENT,
  49                         'Desktop':interfaces.ATSPI_DESKTOP,
  50                         'Document':interfaces.ATSPI_DOCUMENT,
  51                         'EditableText':interfaces.ATSPI_EDITABLE_TEXT,
  52                         'Hypertext':interfaces.ATSPI_HYPERTEXT,
  53                         'Hyperlink':interfaces.ATSPI_HYPERLINK,
  54                         'Image':interfaces.ATSPI_IMAGE,
  55                         'Selection':interfaces.ATSPI_SELECTION,
  56                         'StreamableContent':interfaces.ATSPI_STREAMABLE_CONTENT,
  57                         'Table':interfaces.ATSPI_TABLE,
  58                         'Text':interfaces.ATSPI_TEXT,
  59                         'Value':interfaces.ATSPI_VALUE,
  60                 }
  61
  62                 def return_query(interface):
  63                         def new_query(self):
  64                                 return self.queryInterface(interface)
  65                         return new_query
  66
  67                 for interface in queryable_interfaces.keys():
  68                         name = 'query%s' % interface
  69                         setattr(cls, name, return_query(queryable_interfaces[interface]))
  70
  71                 return cls
  72
  73 #------------------------------------------------------------------------------
  74
  75 class BaseProxy(object):
  76         """
  77         The base D-Bus proxy for a remote object that implements one or more
  78         of the AT-SPI interfaces.
  79         """
  80
  81         __metaclass__ = BaseProxyMeta
  82
  83         def __init__(self, app_name, acc_path, cache, interface, dbus_object=None):
  84                 """
  85                 Create a D-Bus Proxy for an ATSPI interface.
  86
  87                 cache - ApplicationCache, where the cached data for the accessible can be obtained.
  88                 app_name - D-Bus bus name of the application this accessible belongs to.
  89                 acc_path - D-Bus object path of the server side accessible object.
  90                 parent - Parent accessible.
  91                 dbus_object(kwarg) - The D-Bus proxy object used by the accessible for D-Bus method calls.
  92                 """
  93                 self._cache = cache
  94                 self._app_name = app_name
  95                 self._acc_path = acc_path
  96                 self._dbus_interface = interface
  97
  98                 if not dbus_object:
  99                         dbus_object = cache.connection.get_object(self._app_name,
 100                                                                   self._acc_path,
 101                                                                   introspect=False)
 102                 self._dbus_object = dbus_object
 103
 104                 self._pgetter = self.get_dbus_method("Get",
 105                                                      dbus_interface="org.freedesktop.DBus.Properties")
 106                 self._psetter = self.get_dbus_method("Set",
 107                                                      dbus_interface="org.freedesktop.DBus.Properties")
 108
 109         def __str__(self):
 110                     try:
 111                               return '[%s | %s]' % (self.getRoleName(), self.name)
 112                     except Exception:
 113                               return '[DEAD]'
 114
 115         def __eq__(self, other):
 116                 if other is None:
 117                         return False
 118                 try:
 119                         if self._app_name == other._app_name and \
 120                            self._acc_path == other._acc_path:
 121                                 return True
 122                         else:
 123                                 return False
 124                 except AttributeError:
 125                         return False
 126
 127         def __ne__(self, other):
 128                 return not self.__eq__(other)
 129
 130         def get_dbus_method(self, *args, **kwargs):
 131                 method =  self._dbus_object.get_dbus_method(*args, **kwargs)
 132
 133                 def dbus_method_func(*iargs, **ikwargs):
 134                         # TODO Need to throw an AccessibleObjectNoLongerExists exception
 135                         # on D-Bus error of the same type.
 136                         try:
 137                                 return method(*iargs, **ikwargs)
 138                         except UnknownMethodException, e:
 139                                 raise NotImplementedError(e)
 140                         except DBusException, e:
 141                                 raise LookupError(e)
 142
 143                 return dbus_method_func
 144
 145         @property
 146         def cached_data(self):
 147                 try:
 148                         return self._cache.get_cache_data(self._app_name, self._acc_path)
 149                 except KeyError:
 150                         raise AccessibleObjectNoLongerExists, \
 151                                 'Cache data cannot be found for path %s in app %s' % (self._acc_path, self._app_name)
 152
 153         @property
 154         def interfaces(self):
 155                 return self.cached_data.interfaces
 156
 157         def queryInterface(self, interface):
 158                 """
 159                 Gets a different accessible interface for this object
 160                 or raises a NotImplemented error if the given interface
 161                 is not supported.
 162                 """
 163                 if interface in self.interfaces:
 164                         return self._cache.create_accessible(self._app_name,
 165                                                              self._acc_path,
 166                                                              interface,
 167                                                              dbus_object=self._dbus_object)
 168                 else:
 169                         raise NotImplementedError(
 170                                 "%s not supported by accessible object at path %s"
 171                                 % (interface, self._acc_path))
 172
 173 #END----------------------------------------------------------------------------