[Mattj] Fix connection to facebook server that don't understand ver="" in roster query. Fixes #5600

src/common/connection_handlers.py

@@ -636,9 +636,14 @@ class ConnectionVcard:
             else:
                 if iq_obj.getErrorCode() not in ('403', '406', '404'):
                     self.private_storage_supported = False
+
             # We can now continue connection by requesting the roster
-            version = gajim.config.get_per('accounts', self.name,
+            version = None
+            if con.Stream.features.getTag('ver',
+            namespace=common.xmpp.NS_ROSTER_VER):
+                version = gajim.config.get_per('accounts', self.name,
                     'roster_version')
+
             iq_id = self.connection.initRoster(version=version)
             self.awaiting_answers[iq_id] = (ROSTER_ARRIVED, )
         elif self.awaiting_answers[id_][0] == ROSTER_ARRIVED:

src/common/xmpp/protocol.py

@@ -96,6 +96,7 @@ NS_PUBSUB_OWNER ='http://jabber.org/protocol/pubsub#owner'
 NS_REGISTER      ='jabber:iq:register'
 NS_ROSTER          ='jabber:iq:roster'
 NS_ROSTERX        ='http://jabber.org/protocol/rosterx'                            # XEP-0144
+NS_ROSTER_VER    ='urn:xmpp:features:rosterver'               # XEP-0273
 NS_RPC            ='jabber:iq:rpc'                                                                              # XEP-0009
 NS_SASL          ='urn:ietf:params:xml:ns:xmpp-sasl'
 NS_SEARCH          ='jabber:iq:search'

src/common/xmpp/roster_nb.py

@@ -38,7 +38,7 @@ class NonBlockingRoster(PlugIn):
     internal representation of contacts in roster
     """
 
-    def __init__(self, version=''):
+    def __init__(self, version=None):
         """
         Init internal variables
         """
@@ -60,7 +60,8 @@ class NonBlockingRoster(PlugIn):
             return
 
         iq = Iq('get', NS_ROSTER)
-        iq.setTagAttr('query', 'ver', self.version)
+        if self.version is not None:
+            iq.setTagAttr('query', 'ver', self.version)
         id_ = self._owner.getAnID()
         iq.setID(id_)
         self._owner.send(iq)