The specs replace the transports the e2e homeserver advertises with each
shape a migrating deployment may produce and record which token endpoints
each side used: a url-only or combined transport on both sides goes
through the CS API alone, a legacy guest joining a url host uses the
legacy endpoint to publish and the CS API to subscribe, a subscriber falls
back to the JWT service when the homeserver lacks MSC4195, a publisher
gets an error instead, a delayed leave delegated through the CS API fires
on disconnect, and subscribers get tokens for a remote homeserver's SFU
over federation.
The JWT service's app service registration has to cover users of the e2e
Synapse's real server name for the get_token flow, and lk-jwt-service
0.8.0 implements the endpoints.
The developer setting that overrode the LiveKit service URL becomes a
JSON transport, so that a `url`-only or combined transport can be tested
against a homeserver that does not advertise one yet. The settings modal
shows each LiveKit room's role instead of a never-populated isLocal flag.
src/livekit/auth now fronts two flows. For a transport with a LiveKit SFU
`url`, tokens come from our own homeserver's MSC4195 get_token endpoint
and delayed leaves are delegated through delegate_delayed_leave, both via
the js-sdk's unstable client methods. Transports with only a
livekit_service_url keep using the OpenID flow against the JWT service.
A transport advertising both shapes lets a subscriber fall back to the
OpenID flow when the homeserver answers get_token with a 404 (Synapse
reports M_UNRECOGNIZED for unknown routes rather than M_NOT_FOUND), so a
client can still join calls hosted on servers that have not deployed
MSC4195 yet. Publishers never fall back: a homeserver that advertises a
`url` but does not implement the endpoints is misconfigured and the
admin should hear about it, so they get NoMatrix2AuthorizationService.
Delegation uses the same flow as the token so that the participant
identity the service computes matches.
The local member only probes a transport's delegate_delayed_leave
endpoint when it has a service URL. The developer settings tab validates
a custom service URL through the same facade.
Temporary, until matrix-org/matrix-js-sdk#5588 merges and this can go
back to a develop bump. The branch only changes the get_token request
body from a member object to a member_id, so this is kept separate from
the code that uses it and can be dropped without touching that code.
A transport with only a LiveKit SFU `url` has to be authenticated through
our own homeserver, which needs to know the name of the server owning the
SFU. Carry that name alongside the transport as a TransportLocator,
derived from the member's user ID for remote transports and from the
client's domain for our own, and key the connection map on the SFU URL,
the service URL and the server name together so that `url`, service URL
and combined transport shapes are deduplicated consistently.
UnstableLivekitTransport covers every shape a homeserver may advertise
while MSC4195 evolves: a LiveKit SFU `url`, a `livekit_service_url`, or
both. Switching to it means a service URL is no longer guaranteed, so the
remaining code that relies on one checks for it explicitly: delegation
probing skips transports without one, the connection map keys transports
by whichever URL they carry, and the OpenID flow rejects transports
without a service URL until the client-server API flow lands.
createConnectionMap$ now returns the behavior of connections and their
participants directly and takes an already resolved local transport
instead of an observable of it. The CallViewModel wraps it with mapScoped
so that a new map is built, in a fresh scope, whenever the local transport
changes, and swallows local transport errors there since the local member
already surfaces them in the UI.
getLocalTransport no longer authenticates with the SFU up front and hands
the resulting config to the connection. Instead the ConnectionManager tags
the connection whose transport equals the local one as the publisher, and
every Connection fetches its own SFU config for its role.
The local member now only joins the MatrixRTC session once its connection
is authenticated, so that the LiveKit room exists before remote members
try to get a subscriber token for it. Subscribers authenticating with the
OpenID flow lack permission to create the room and would otherwise fail
without retrying, causing a cascade of leaves and rejoins at the start of
a call.
The OpenID flow moves to src/livekit/auth/openID.ts with the SFU config
types in a sibling file, takes an options object, and replaces the
MatrixRTC mode with the role we take on the transport plus the session's
slot ID instead of a hard-coded m.call#ROOM.
This changes behaviour: publishers on a livekit_service_url transport
always use the legacy /sfu/get endpoint, so that subscribers can predict
their user:device participant identity, and subscribers always use the
default /get_token endpoint. The MatrixRTC mode no longer influences which
endpoint is used.
The old reducer keyed items by service URL and mutated the accumulator's
entries in place, so a transport without a service URL could not be
represented and items were not safe to compare. Group members by their
Connection object instead and carry the whole transport on the item, which
the audio renderer now receives in place of a URL.
A transport may soon carry a LiveKit SFU `url` instead of, or as well as,
a `livekit_service_url`, so a service URL alone no longer identifies it.
Pass the whole transport to the tiles' debug stats and print it as JSON in
log lines instead of picking out the service URL.
The enum mixed our own lifecycle states with a copy of livekit-client's
connection states, and errors were smuggled through the same observable as
a separate union member. A discriminated union keeps the LiveKit state
nested under "authenticated", carries the error as data, and lets the
local member represent the time before a connection exists as an
"initializing" state instead of null.
A member authenticated through the legacy JWT endpoint publishes under a
`user:device` identity, while one authenticated through the default
endpoint publishes under a hashed identity. Both are listed in the
membership's backend identities, so match against the whole list rather
than only the primary one.
The container IP is not routable from the host when Docker runs in a VM
(colima, Docker Desktop), so calls against the dev stack drop once ICE
fails. Advertising 127.0.0.1 instead lets the browser reach the SFU through
the published ports. Firefox ignores loopback candidates, so this only
works in Chromium-based browsers.
The list reporter is the only progress a hung CI run leaves behind, and a
global timeout under the job's 60 minute limit means a hung run still ends
with a report instead of being cancelled by GitHub.
The SDK now takes `publish` requests and audio output control directly
in the main options object, removing the separate `LocalMediaInputs`
type. Audio output device selection moves from a reactive behavior to an
imperative method on `MatrixRTCClient`, giving hosts direct control over
when devices switch.
The session speaks MatrixRTC and sees media through MediaBackend in
sdk/src/backend/api.ts. Everything LiveKit lives in
sdk/src/backend/livekit/,
the only place in the SDK that imports livekit-client; the import
boundary rule
now enforces that outside sdk/src/backend/ the LiveKit packages appear
in type
imports only.
The seam sits above the connection manager: one connection per transport
url
is the LiveKit multi-SFU strategy, not a MatrixRTC concept, so a
cascading SFU
or full mesh replaces the folder, not the session. A backend prepares
the local
transport the session discovered (the token exchange and the delegation
probe,
reported as canDelegateDelayedLeave), hands the delayed leave over per
delay
id, gives the local member one publish switch plus publish/unpublish,
builds a
remote member's media from its membership and registers that
membership's
transport for as long as the member lives, and reports its connections
for the
transport registry, which keys on the raw transport serialised with
sorted
keys. The backend's context carries no Matrix client (a backend picks
what it
calls in its own options), no membership list, and no js-sdk session:
media
keys arrive as a stream replayed on subscribe, and MatrixKeyProvider
subscribes
to it. The MatrixRTC mode no longer reaches LiveKit; it becomes a
tokenEndpoint
choice made where the default backend is built.
Two behaviour changes ride along. Publishing is one boolean, joined and
homeserver reachable, where before a sync hiccup after leave() resumed
the
upstream of tracks that were meant to stay silent. And
ResolvedConnection keeps
one ResolvedTransport object per fetch, so a state change no longer
reads as a
change of what was fetched.
MatrixRTCClientOptions gains backend?: MediaBackendFactory, defaulting
to
createLivekitBackend built from the client options.
authenticateWithTransport
takes tokenEndpoint instead of matrixRTCMode.
Timo K.