Fall back to publishing on a remote SFU if possible

Port of edf1feae from johannes/rtc-remote-publish onto the SDK split,
where
the MatrixRTC logic lives in sdk/ rather than src/state/CallViewModel/.

Where the original lands:

- getLocalTransport's remote fallback: the LiveKit backend's new
  findRemotePublishTransport (sdk/src/media-backend/livekit/
  RemotePublishTransport.ts), which tries the candidates from the
  js-sdk's
  getRemoteLivekitPublishCandidates oldest first and keeps the first
  whose
  homeserver issues a token with the publish grant.
  discoverLocalTransport
  asks the backend for it after the host's fallback, with a snapshot of
  the
  session's memberships from RTCParticipation, and throws
  MatrixRTCTransportMissingError where that finds nothing too. Transport
  discovery stays backend neutral: the MSC4195 token check is the
  backend's.
- LocalMember's "no delegation on a remote SFU" and the custom
  transport's
  server_name: LivekitBackend.prepareLocalTransport locates the
  transport on
  the homeserver it names (serverNameOfTransport) and skips the
  delegation
  probe where that is not our own.
- SessionBehaviors' membership.getTransportServerName: the same helper
  in
  LivekitBackend.mediaFor.
- decodeSFUJWTPayload, SFUJWTPayload.video.canPublish and the exported
  isCsApiUnavailable: sdk/src/media-backend/livekit/auth/.
- DeveloperSettingsTab, the widget capabilities, the locale string and
  the
  js-sdk pin (9405287c, 44.0.0): applied as is. The error boundary
  snapshots follow the string.

Tests: the LocalTransport cases go to RemotePublishTransport.test.ts and
LocalTransport.test.ts, the LocalMember remote case and the
SessionBehaviors
server-name case to LivekitBackend.test.ts, plus the memberships
snapshot in
RTCParticipation.test.ts.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
This commit is contained in:
Timo K.
2026-10-14 16:09:11 +02:00
co-authored by Claude Fable 5.1
parent 4b73ce68e3
commit 8638d4f159
20 changed files with 527 additions and 51 deletions
+1 -1
View File
@@ -106,7 +106,7 @@
"insufficient_capacity_description": "The server has reached its maximum capacity and you cannot join the call at this time. Try again later, or contact your server admin if the problem persists.",
"livekit_connection_error": "Failed to connect to Livekit server",
"livekit_connection_error_description": "An error occurred while connecting to the Livekit server (<1>Reason:</1> <2>{{ reason }}</2>).",
"matrix_rtc_transport_missing": "The server is not configured to work with {{brand}}. Please contact your server admin (Domain: {{domain}}, Error Code: {{ errorCode }}).",
"matrix_rtc_transport_missing": "The server is not configured to work with {{brand}} and no other call participant provides a usable transport. Please contact your server admin (Domain: {{domain}}, Error Code: {{ errorCode }}).",
"membership_manager": "Membership Manager Error",
"membership_manager_description": "The Membership Manager had to shut down. This is caused by many consecutive failed network requests.",
"no_matrix_2_authorization_service": "The authorization service for your media server (SFU) is out of date.",