XEP-0424: Add an event for message retraction

+ update the integration test

itests/test_retract.py

@@ -22,7 +22,7 @@ class TestRetract(SlixIntegration):
             id='toto',
             fallback_text='Twas a mistake',
         )
-        msg = await self.clients[1].wait_until('message')
+        msg = await self.clients[1].wait_until('message_retract')
         self.assertEqual(msg['apply_to']['id'], 'toto')
         self.assertTrue(msg['apply_to']['retract'])
 

slixmpp/plugins/xep_0424/retraction.py

@@ -9,6 +9,8 @@ from typing import Optional
 
 from slixmpp import JID, Message
 from slixmpp.exceptions import IqError, IqTimeout
+from slixmpp.xmlstream.matcher import StanzaPath
+from slixmpp.xmlstream.handler import Callback
 from slixmpp.plugins import BasePlugin
 from slixmpp.plugins.xep_0424 import stanza
 
@@ -30,6 +32,11 @@ class XEP_0424(BasePlugin):
 
     def plugin_init(self) -> None:
         stanza.register_plugins()
+        self.xmpp.register_handler(Callback(
+            "Message Retracted",
+            StanzaPath("message/apply_to/retract"),
+            self._handle_retract_message,
+        ))
 
     def session_bind(self, jid):
         self.xmpp.plugin['xep_0030'].add_feature(feature=stanza.NS)
@@ -37,6 +44,10 @@ class XEP_0424(BasePlugin):
     def plugin_end(self):
         self.xmpp.plugin['xep_0030'].del_feature(feature=stanza.NS)
 
+    def _handle_retract_message(self, message: Message):
+        if message['type'] != 'groupchat':
+            self.xmpp.event('message_retract', message)
+
     def send_retraction(self, mto: JID, id: str, mtype: str = 'chat',
                         include_fallback: bool = True,
                         fallback_text: Optional[str] = None, *,