D-Bus Bridge: use inspection to name attribute + fix asynchronous calls for dynamically added method, it now use deferred return value instead of callback/errback attributes

src/bridge/bridge_constructor/dbus_core_template.py

@@ -24,6 +24,7 @@ from bridge import Bridge
 import dbus
 import dbus.service
 import dbus.mainloop.glib
+import inspect
 from logging import debug, info, error
 from twisted.internet.defer import Deferred
 
@@ -82,7 +83,7 @@ class DbusObject(dbus.service.Object):
             if not isinstance(result, Deferred):
                 error("Asynchronous method [%s] does not return a Deferred." % name)
                 raise AsyncNotDeferred
-            result.addCallback(callback)
+            result.addCallback(lambda result: callback() if result==None else callback(result))
             result.addErrback(lambda err:errback(GenericException(err)))
         else:
             if isinstance(result, Deferred):
@@ -142,17 +143,32 @@ class DbusObject(dbus.service.Object):
             i+=1
         return attr
 
-    def addMethod(self, name, int_suffix, in_sign, out_sign, async=False, doc={}):
+    def addMethod(self, name, int_suffix, in_sign, out_sign, method, async=False):
         """Dynamically add a method to Dbus Bridge"""
-        _attributes = self.__attributes(in_sign)
+        inspect_args = inspect.getargspec(method)
+
+        _attributes = inspect_args.args
+        _defaults = list(inspect_args.defaults or [])
+        
+        if inspect.ismethod(method):
+            #if we have a method, we don't want the first argument (usually 'self')
+            del(_attributes[0])
 
         if async:
             _attributes.extend(['callback','errback'])
+            _defaults.extend(['callback', 'errback'])
         
         attributes = ', '.join(_attributes)
+        
+        #now we create a second list with default values
+        for i in range(1, len(_defaults)+1):
+            _attributes[-i] = "%s = %s" % (_attributes[-i], repr(_defaults[-i]))
 
-        code = compile ('def '+name+' (self,'+attributes+'): return self.cb["'+name+'"]('+attributes+')', '<DBus bridge>','exec')
-        exec (code)
+        attributes_defaults =  ', '.join(_attributes)
+
+        code = compile ('def %(name)s (self,%(attributes_defaults)s): return self.cb["%(name)s"](%(attributes)s)' %
+                        {'name':name, 'attributes_defaults':attributes_defaults, 'attributes':attributes}, '<DBus bridge>','exec')
+        exec (code) #FIXME: to the same thing in a cleaner way, without compile/exec
         method = locals()[name]
         async_callbacks = ('callback', 'errback') if async else None
         setattr(DbusObject, name, dbus.service.method(
@@ -165,6 +181,7 @@ class DbusObject(dbus.service.Object):
     def addSignal(self, name, int_suffix, signature, doc={}):
         """Dynamically add a signal to Dbus Bridge"""
         attributes = ', '.join(self.__attributes(signature))
+        #TODO: use doc parameter to name attributes
 
         #code = compile ('def '+name+' (self,'+attributes+'): debug ("'+name+' signal")', '<DBus bridge>','exec') #XXX: the debug is too annoying with xmllog
         code = compile ('def '+name+' (self,'+attributes+'): pass', '<DBus bridge>','exec')
@@ -193,8 +210,9 @@ class DBusBridge(Bridge):
 
     def addMethod(self, name, int_suffix, in_sign, out_sign, method, async=False, doc={}):
         """Dynamically add a method to Dbus Bridge"""
+        #FIXME: doc parameter is kept only temporary, the time to remove it from calls
         print ("Adding method [%s] to DBus bridge" % name)
-        self.dbus_bridge.addMethod(name, int_suffix, in_sign, out_sign, async, doc)
+        self.dbus_bridge.addMethod(name, int_suffix, in_sign, out_sign, method, async)
         self.register(name, method)
 
     def addSignal(self, name, int_suffix, signature, doc={}):