Merge lp:~laney/python-dbusmock/introspection-properties into lp:~pitti/python-dbusmock/old-bzr-trunk

[Iain Lane]

The introspection XML currently doesn't include <property> nodes, breaking some things which rely on it such as Qt's property support.

I found an old-ish dbus-python bug about adding this there but it doesn't seem to have gained much traction:

  https://bugs.freedesktop.org/show_bug.cgi?id=26903

Since we already override Introspect(), I figure it's not too bad to add this there even if it is a bit ugly.

One wart:

+ # copy.copy removes one level of variant-ness, which means that the
+ # types get exported in introspection data correctly, but we can't do
+ # this for container types.
+ if not (isinstance(value, dbus.Dictionary) or isinstance(value, dbus.Array)):
+ value = copy.copy(value)

While the support works for properties added via the python library (e.g. in templates) without this, dynamic proeprties added using AddProperty over dbus don't. If you remove this and run the testsuite you'll see what I mean. AddPropert{y,ies} get type 'v' when introspected. We probably want them to have the actual types, so this tries to unpack the variant by one level (you can't just decrement variant_level as the object is immutable; copying it doesn't preseve this). It breaks for container types though, so we don't do this there—again, remove that bit and see what happens to the NM tests. I'd be glad to replace this with something better if you can think of an improved way around.

The test changes are because we now take the XML through a parser which changes the order of the arguments. Shouldn't be anything clients need to worry about.

[Martin Pitt (pitti)]

Thanks a lot for this! That's indeed a long-standing wart. I merged it with some stylistic changes and changing properties to be readwrite.

review: Approve

=== modified file 'dbusmock/mockobject.py'
--- dbusmock/mockobject.py	2013-11-29 09:22:03 +0000
+++ dbusmock/mockobject.py	2013-12-13 10:44:10 +0000
@@ -12,10 +12,12 @@
 __copyright__ = '(c) 2012 Canonical Ltd.'
 __license__ = 'LGPL 3+'
 
+import copy
 import time
 import sys
 import types
 import importlib
+import xml.etree.ElementTree as ET
 
 # we do not use this ourselves, but mock methods often want to use this
 import os
@@ -367,6 +369,13 @@
         except KeyError:
             # this is what we expect
             pass
+
+        # copy.copy removes one level of variant-ness, which means that the
+        # types get exported in introspection data correctly, but we can't do
+        # this for container types.
+        if not (isinstance(value, dbus.Dictionary) or isinstance(value, dbus.Array)):
+            value = copy.copy(value)
+
         self.props.setdefault(interface, {})[name] = value
 
     @dbus.service.method(MOCK_IFACE,
@@ -613,6 +622,29 @@
 
         xml = dbus.service.Object.Introspect(self, object_path, connection)
 
+        tree = ET.fromstring(xml)
+
+        for name in self.props:
+            # We might have properties for new interfaces we don't know about
+            # yet. Try to find an existing <interface> node named after our
+            # interface to append to, and create one if we can't.
+            interface = tree.find(".//interface[@name='%s']" % name)
+            if interface is None:
+                interface = ET.Element("interface", {"name": name})
+                tree.append(interface)
+
+            for prop in self.props[name]:
+                elem = ET.Element("property", {
+                    "name": prop,
+                    # We don't store the signature anywhere, so guess it.
+                    "type": dbus.lowlevel.Message.guess_signature(self.props[name][prop]),
+                    # Assume read-only.
+                    "access": "read"})
+
+                interface.append(elem)
+
+        xml = ET.tostring(tree, encoding='utf8', method='xml').decode('utf8')
+
         # restore original class table
         self._dbus_class_table[cls] = orig_interfaces
 

=== modified file 'tests/test_api.py'
--- tests/test_api.py	2013-12-12 08:14:35 +0000
+++ tests/test_api.py	2013-12-13 10:44:10 +0000
@@ -305,24 +305,25 @@
         self.assertFalse(xml_empty == xml_method, 'No change from empty XML')
         self.assertTrue('<interface name="org.freedesktop.Test.Main">' in xml_method, xml_method)
         self.assertTrue('''<method name="Do">
-      <arg direction="in"  type="s" name="arg1" />
-      <arg direction="in"  type="ai" name="arg2" />
-      <arg direction="in"  type="v" name="arg3" />
+      <arg direction="in" name="arg1" type="s" />
+      <arg direction="in" name="arg2" type="ai" />
+      <arg direction="in" name="arg3" type="v" />
       <arg direction="out" type="i" />
     </method>''' in xml_method, xml_method)
 
     # properties in introspection are not supported by dbus-python right now
-    #def test_introspection_properties(self):
-    #    '''dynamically added properties appear in introspection'''
-
-    #    self.dbus_mock.AddProperty('', 'Color', 'yellow')
-    #    self.dbus_mock.AddProperty('org.freedesktop.Test.Sub', 'Count', 5)
-
-    #    xml = self.obj_test.Introspect(dbus_interface=dbus.INTROSPECTABLE_IFACE)
-    #    self.assertTrue('<interface name="org.freedesktop.Test.Main">' in xml, xml)
-    #    self.assertTrue('<interface name="org.freedesktop.Test.Sub">' in xml, xml)
-    #    self.assertTrue('<property name="Color" type="s" access="read" />' in xml, xml)
-    #    self.assertTrue('<property name="Count" type="i" access="read" />' in xml, xml)
+    def test_introspection_properties(self):
+        '''dynamically added properties appear in introspection'''
+
+        self.dbus_mock.AddProperty('', 'Color', 'yellow')
+        self.dbus_mock.AddProperty('org.freedesktop.Test.Sub', 'Count', 5)
+
+        xml = self.obj_test.Introspect()
+
+        self.assertTrue('<interface name="org.freedesktop.Test.Main">' in xml, xml)
+        self.assertTrue('<interface name="org.freedesktop.Test.Sub">' in xml, xml)
+        self.assertTrue('<property access="read" name="Color" type="s" />' in xml, xml)
+        self.assertTrue('<property access="read" name="Count" type="i" />' in xml, xml)
 
     def test_objects_map(self):
         '''access global objects map'''
@@ -635,8 +636,8 @@
         xml = dbus_objmgr.Introspect()
         self.assertIn('<interface name="org.freedesktop.DBus.ObjectManager">', xml)
         self.assertIn('<method name="GetManagedObjects">', xml)
-        self.assertIn('<node name="Thing1"/>', xml)
-        self.assertIn('<node name="Thing2"/>', xml)
+        self.assertIn('<node name="Thing1" />', xml)
+        self.assertIn('<node name="Thing2" />', xml)
 
     def test_reset(self):
         '''Reset() puts the template back to pristine state'''