python/rox/session.py

   1 """Contact ROX-Session via the DBus or XMLRPC interface.  Using get_session()
   2 will return a proxy object on which you can make remote calls to control
   3 the session.  Similarly get_settings() will return an object to control
   4 session settings, e.g.
   5
   6   try:
   7     settings = session.get_settings()
   8     type, value = settings.GetSetting('Gtk/KeyThemeName')
   9   except:
  10     # No ROX-Session available, do something else
  11
  12 In addition the Setting class is provided which derives from rox.options.Option
  13 but has two important differences: it is not saved to the options file and
  14 it is synchronized with a value of the same name in the ROX-Session settings.
  15 """
  16
  17 import rox
  18 import rox.xxmlrpc
  19 # import gobject
  20
  21 try:
  22     import dbus
  23     dbus_ok=(dbus.version>=(0, 42, 0))
  24 except:
  25     dbus_ok=False
  26
  27 if dbus_ok:
  28     bus = dbus.Bus(dbus.Bus.TYPE_SESSION)
  29 else:
  30     bus = None
  31
  32 session_service = "net.sf.rox.Session"
  33 control_object = '/Session'
  34 control_interface = 'net.sf.rox.Session.Control'
  35 settings_interface = 'net.sf.rox.Session.Settings'
  36 settings_object = '/Settings'
  37
  38 def _dbus_get_proxy(bus, service_name, object_name, interface_name):
  39     """For internal use. Do not call this, call get_proxy() instead."""
  40     try:
  41         service = bus.get_service(service_name)
  42         obj = service.get_object(object_name, interface_name)
  43         proxy = obj
  44     except AttributeError:
  45         obj = bus.get_object(service_name, object_name)
  46         iface = dbus.Interface(obj, interface_name)
  47         proxy = iface
  48     return proxy
  49
  50 class _caller:
  51     """For internal use."""
  52     def __init__(self, method):
  53         self.method=method
  54
  55     def __call__(self, *params):
  56         client=self.method(*params)
  57         return client.get_response()
  58
  59 class _RPCProxy:
  60     """For internal use."""
  61     def __init__(self, obj):
  62         self.obj=obj
  63
  64     def __getattr__(self, method):
  65         invoke=self.obj.__getattr__(method)
  66         return _caller(invoke)
  67
  68 def _xxmlrpc_get_proxy(service_name, object_name, interface_name):
  69     """For internal use. Do not call this, call get_proxy() instead."""
  70     proxy=rox.xxmlrpc.XXMLProxy(service_name)
  71     return _RPCProxy(proxy.get_object(object_name))
  72
  73 def get_proxy(service_name, object_name, interface_name):
  74     """Get a proxy object for the required service, object path and interface.
  75     This selects an appropriate transport for you, either DBus or XMLRPC."""
  76     if dbus_ok and bus:
  77         return _dbus_get_proxy(bus, service_name, object_name, interface_name)
  78     return _xxmlrpc_get_proxy(service_name, object_name, interface_name)
  79
  80 def get_session():
  81     """Return a proxy object for the ROX-Session settings interface"""
  82     return get_proxy(session_service, control_object,
  83                      control_interface)
  84
  85 def get_settings():
  86     """Return a proxy object for the ROX-Session control interface"""
  87     return get_proxy(session_service, settings_object,
  88                      settings_interface)
  89
  90 def running():
  91     """Return True if ROX-Session is detected as running"""
  92     if not dbus_ok or not bus:
  93         proxy=_xxmlrpc_get_proxy(session_service, control_object,
  94                                  control_interface)
  95         return proxy is not None
  96     try:
  97         proxy = get_proxy('org.freedesktop.DBus', '/org/freedesktop/DBus',
  98                           'org.freedesktop.DBus')
  99     except:
 100         return False
 101
 102     try:
 103         services = proxy.ListServices()
 104     except:
 105         services = proxy.ListNames()
 106
 107     return session_service in services
 108
 109 if bus and not running():
 110     bus=None
 111
 112 # Test routine
 113 if __name__=='__main__':
 114     print 'Session running? %s' % running()
 115     settings=get_settings()
 116
 117     def test_get(name):
 118         try:
 119             v=settings.GetSetting(name)
 120             print '%s = %s' % (name, v)
 121         except Exception, exc:
 122             print "Can't get %s: %s" % (name, exc)
 123
 124     test_get('Gtk/KeyThemeName')
 125     test_get('Net/ThemeName')
 126
 127     control=get_session()
 128     control.ShowMessages()