Refactor lobby system to use consistent UUID v4 across lobby
registration and LiveKit token participant identity instead of
generating separate UUIDs.
Maintains synchronized identifiers between lobby cache and LiveKit
participants, simplifying future participant removal operations by
using the same UUID reference across both systems.
Extend LiveKit token creation utility with additional room configuration
and user role parameters to properly adapt room_admin grants and
publish sources based on permission levels.
This creates technical debt in utility function design that should be
refactored into proper service architecture for token
generation operations in future iterations.
Allow any user, anonymous or authenticated, to start subtitling
in a room only if they are an active participant of it.
Subtitling a room consists of starting the multi-user transcriber agent.
This agent forwards all participants' audio to an STT server and returns
transcription segments for any active voice to the room.
User roles in the backend room system cannot be used
to determine subtitle permissions.
The transcriber agent can be triggered multiple times but will only join a
room once. Unicity is managed by the agent itself.
Any user with a valid LiveKit token can initiate subtitles. Feature flag
logic is implemented on the frontend. The frontend ensures the "start
subtitle" action is only available to users who should see it. The backend
does not enforce feature flags in this version.
Authentication in our system does not imply access to a room. The only
valid proof of access is the LiveKit API token issued by the backend.
Security consideration: A LiveKit API token is valid for 6 hours and
cannot be revoked at the end of a meeting. It is important to verify
that the token was issued for the correct room.
Calls to the agent dispatch endpoint must be server-initiated. The backend
proxies these calls, as clients cannot securely contact the agent dispatch
endpoint directly (per LiveKit documentation).
Room ID is passed as a query parameter. There is currently no validation
ensuring that the room exists prior to agent dispatch.
TODO: implement validation or error handling for non-existent rooms.
The backend does not forward LiveKit tokens to the agent. Default API
rate limiting is applied to prevent abuse.
Implement method to process egress limit reached events from LiveKit
webhooks for better recording duration management.
Livekit by default is not notifying the participant of a room when
an egress reached its limit. I needed to proxy it through the back.
Move from lobby service to utils for reuse across services. Method is
generic enough for utility status. Future: create dedicated LiveKit
service to encapsulate all LiveKit-related utilities.
Implemented a service that automatically creates a SIP dispatch rule when
the first WebRTC participant joins a room and removes it when the room
becomes empty.
Why? I don’t want a SIP participant to join an empty room.
The PIN code could be easily leaked, and there is currently no lobby
mechanism available for SIP participants.
A WebRTC participant is still required to create a room.
This behavior is inspired by a proprietary tool. The service uses LiveKit’s
webhook notification system to react to room lifecycle events. This is
a naive implementation that currently supports only a single SIP trunk and
will require refactoring to support multiple trunks. When no trunk is
specified, rules are created by default on a fallback trunk.
@rouja wrote a minimal Helm chart for LiveKit SIP with Asterisk, which
couldn’t be versioned yet due to embedded credentials. I deployed it
locally and successfully tested the integration with a remote
OVH SIP trunk.
One point to note: LiveKit lacks advanced filtering capabilities when
listing dispatch rules. Their recommendation is to fetch all rules and
filter them within your backend logic. I’ve opened a feature request asking
for at least the ability to filter dispatch rules by room, since filtering
by trunk is already supported, room-based filtering feels like a natural
addition.
Until there's an update, I prefer to keep the implementation simple.
It works well at our current scale, and can be refactored when higher load
or multi-trunk support becomes necessary.
While caching dispatch rule IDs could be a performance optimization,
I feel it would be premature and potentially error-prone due to the complexity
of invalidation. If performance becomes an issue, I’ll consider introducing
caching at that point. To handle the edge case where multiple dispatch rules
with different PIN codes are present, the service performs an extensive
cleanup during room creation to ensure SIP routing remains clean and
predictable. This edge case should not happen.
In the 'delete_dispatch_rule' if deleting one rule fails, method would exit
without deleting the other rules. It's okay IMO for a first iteration.
If multiple dispatch rules are often found for room, I would enhance this part.
Handle unhandled exceptions to prevent UX impact. Marketing email operations
are optional and should not disrupt core functionality.
My first implementation was imperfect, raising error in sentry.
Create dedicated utility function for livekit API client initialization.
Centralizes configuration logic including custom session handling for SSL
verification. Improves code reuse across backend components that interact
with LiveKit.
Implement new endpoint allowing admin/owner to invite participants via email.
Provides explicit way to search users and send meeting invitations with
direct links.
In upcoming commits, frontend will call ResourceAccess endpoint to add
invited people as members if they exist in visio, bypassing waiting room
for a smoother experience.
Necessary in cross browser context situation, where we need to
pass data of a room newly created between two different windows.
This happens in Calendar integration.
Improves sendData reliability by preventing execution when the room
doesn’t exist.
This change addresses errors in staging and production where waiting
participants arrive before the room owner creates the room.
In remote environments, the LiveKit Python SDK doesn’t return a clean
Twirp error when the room is missing; instead of a proper "server unknown"
response, it raises a ContentTypeError, as if the LiveKit server weren’t
responding with a JSON payload, even though the code specifies otherwise.
While the issue cannot be reproduced locally,
this should help mitigate production errors.
Part of a broader effort to enhance data transmission reliability.
Importantly, a participant requesting entry to a room before the owner
arrives should not be considered an exception.
Invert operation sequence to first notify people in room before setting
participant in cache. Fixes infinite loop issue caused by 3s cache timeout
for waiting participants when requests take too long. Problem only occurred
when notifications were delayed, as faster notification delivery masked the
race condition.
Create new service that matches received events with their appropriate
handlers. Provides centralized system for event routing and processing
across the application.
If an event has no handler, it would be ignored.
Implement new lobby service method to clear all participant entries from cache.
Lays foundation for upcoming feature where participant permissions reset when
meetings end. Currently introduces only the cache clearing functionality;
event handling for meeting conclusion will be implemented in future commits
Introduce new intermediate access level between public and restricted that
allows authenticated users to join rooms without admin approval. Not making
this the default level yet as current 12hr sessions would create painful
user experience for accessing rooms. Will reconsider default settings after
improving session management.
This access level definition may evolve to become stricter in the future,
potentially limiting access to authenticated users who share the same
organization as the room admin.
Implement lobby service using cache as LiveKit doesn't natively support
secure lobby functionality. Their teams recommended to create our own
system in our app's backend.
The lobby system is totally independant of the DRF session IDs,
making the request_entry endpoint authentication agnostic.
This decoupling prevents future DRF changes from breaking lobby functionality
and makes participant tracking more explicit.
Security audit is needed as current LiveKit tokens have excessive privileges
for unprivileged users. I'll offer more option ASAP for the admin to control
participant privileges.
Race condition handling also requires improvements, but should not be critical
at this point.
A great enhancement, would be to add a webhook, notifying the backend when the
room is closed, to reset cache.
This commit makes redis a prerequesite to run the suite of tests. The readme
and CI will be updated in dedicated commits.
Introduced a MarketingService protocol for typed marketing operations,
allowing easy integration of alternative services.
Implemented a Brevo wrapper following the protocol to decouple
the codebase from the sdk. These implementations are simple and pragmatic.
Feel free to refactor them.
