plugin XEP-0353, XEP-0234, jingle: WebRTC data channel signaling implementation: Implement XEP-0343: Signaling WebRTC Data Channels in Jingle. The current version of the XEP (0.3.1) has no implementation and contains some flaws. After discussing this on xsf@, Daniel (from Conversations) mentioned that they had a sprint with Larma (from Dino) to work on another version and provided me with this link: https://gist.github.com/iNPUTmice/6c56f3e948cca517c5fb129016d99e74 . I have used it for my implementation. This implementation reuses work done on Jingle A/V call (notably XEP-0176 and XEP-0167 plugins), with adaptations. When used, XEP-0234 will not handle the file itself as it normally does. This is because WebRTC has several implementations (browser for web interface, GStreamer for others), and file/data must be handled directly by the frontend. This is particularly important for web frontends, as the file is not sent from the backend but from the end-user's browser device. Among the changes, there are: - XEP-0343 implementation. - `file_send` bridge method now use serialised dict as output. - New `BaseTransportHandler.is_usable` method which get content data and returns a boolean (default to `True`) to tell if this transport can actually be used in this context (when we are initiator). Used in webRTC case to see if call data are available. - Support of `application` media type, and everything necessary to handle data channels. - Better confirmation message, with file name, size and description when available. - When file is accepted in preflight, it is specified in following `action_new` signal for actual file transfer. This way, frontend can avoid the display or 2 confirmation messages. - XEP-0166: when not specified, default `content` name is now its index number instead of a UUID. This follows the behaviour of browsers. - XEP-0353: better handling of events such as call taken by another device. - various other updates. rel 441

--- a/libervia/backend/plugins/plugin_xep_0176.py	Sat Apr 06 12:21:04 2024 +0200
+++ b/libervia/backend/plugins/plugin_xep_0176.py	Sat Apr 06 12:57:23 2024 +0200
@@ -53,6 +53,8 @@
 
 
 class XEP_0176(BaseTransportHandler):
+    namespace = NS_JINGLE_ICE_UDP
+
     def __init__(self, host):
         log.info(f"plugin {PLUGIN_INFO[C.PI_NAME]!r} initialization")
         self.host = host
@@ -282,6 +284,15 @@
                     content_name,
                     context_elt=transport_elt,
                 )
+                self.host.trigger.point(
+                    "XEP-0176_jingle_handler_send_buffer",
+                    client,
+                    session,
+                    content_name,
+                    content_data,
+                    transport_elt,
+                    iq_elt
+                )
                 await iq_elt.send()
 
         elif action == self._j.A_START:
@@ -370,6 +381,8 @@
         """
         session = self._j.get_session(client, session_id)
         iq_elt: Optional[domish.Element] = None
+        content_name: str|None = None
+        content_data: dict|None = None
 
         for media_type, new_ice_data in media_ice_data.items():
             if session["state"] == self._j.STATE_PENDING:
@@ -420,7 +433,12 @@
             )
 
         if iq_elt is not None:
+            assert content_name is not None and content_data is not None
             try:
+                self.host.trigger.point(
+                    "XEP-0176_ice_candidate_send", client, session, media_ice_data,
+                    content_name, content_data, iq_elt
+                )
                 await iq_elt.send()
             except Exception as e:
                 log.warning(f"Could not send new ICE candidates: {e}")