@bear-block/callx-livekit

LiveKit media adapter for @bear-block/callx. When a call is answered, from the app, the lock screen, a watch or a car, the adapter joins the call's LiveKit room natively, so audio starts even if JavaScript is not running yet (ADR-0009).

Voice calls only. If your app renders video or participants with LiveKit's own React Native SDK, use @bear-block/callx alone and connect LiveKit yourself when the call is answered.

Install

npm install @bear-block/callx @bear-block/callx-livekit

Expo: add both config plugins, then prebuild.

{
  "expo": {
    "plugins": ["@bear-block/callx/app.plugin", "@bear-block/callx-livekit/app.plugin"]
  }
}

React Native CLI: add CallxLiveKitAdapterFactory to the CallxMediaAdapterFactories array in Info.plist, and JitPack to the Android repositories (LiveKit's AudioSwitch dependency):

maven { url "https://jitpack.io"; content { includeGroup "com.github.davidliu" } }

Callx's native bootstrap (CallxModule.bootstrap on Android, CallxReactNativeHost.bootstrap on iOS) finds the adapter; there is no native code to write. On iOS, LiveKit comes through Swift Package Manager (React Native's spm_dependency).

Configure credentials

import {configureLiveKit, resetLiveKit} from '@bear-block/callx-livekit';

// After sign-in, and whenever the session token changes. It persists, so a call answered
// while the app was killed still gets credentials. Headers are stored encrypted.
await configureLiveKit({
  tokenUrl: 'https://api.example.com/calls/livekit-token',
  headers: {authorization: `Bearer ${sessionToken}`},
});

// On sign-out.
await resetLiveKit();

Your backend receives POST tokenUrl with those headers and {"callId": "..."}. It authenticates the user, checks that they belong to the call, and answers {"url": "wss://your-livekit-host", "token": "<LiveKit access token for room call-<callId>>"}.

Hosts that already hold credentials natively can register a provider before bootstrap instead: CallxLiveKit.setCredentialProvider { callId -> LiveKitCredentials(url, token) } (Kotlin) or CallxLiveKit.setCredentialProvider { callID in LiveKitCredentials(url:token:) } (Swift).

What the adapter does

• One LiveKit room per call, joined on answer and left when the call ends.
• Reports mediaReady when the other party's audio arrives and mediaInterrupted while LiveKit reconnects or no remote audio is heard; it never ends or holds the call.
• Android: Telecom owns audio routing (LiveKit's AudioSwitch is off). iOS: CallKit owns the audio session; LiveKit's engine runs only between didActivate and didDeactivate.
• Without the microphone permission the call stays connected and only listens.