call-engine-wx

Pure-JS TUICallEngine for WeChat Mini Program. No WASM.

API shape mirrors @trtc/call-engine-lite-wx so that TUICallKit and existing business code can switch over without changing event names or method signatures.

Why?

The legacy SDK ships a C++ core compiled to WASM plus a JS glue layer. That works, but it adds ~hundreds of KB to the WeChat MP package and requires a WASM-capable runtime. For the subset of API actually used in production we can implement the call state machine directly in JS on top of @tencentcloud/lite-chat and @tencentcloud/trtc-cloud-wx, shaving most of the bundle weight.

call-engine-wx is the JS-only reimplementation. This cut implements login / logout / calls plus the event plumbing. The remaining call-signalling APIs (call / accept / reject / hangup / ...) will land in follow-up increments on top of the same lite-chat session.

Note on transport. calls does NOT use lite-chat's createInvitation / onNewInvitationReceived business APIs. It talks directly to the v3 backend service call_engine_srv via chat.callExperimentalAPI('sendCallEngineSSOPacket', ...) — the same mechanism used by the sibling pure-JS package call-engine-wx. The wire protocol is byte-identical to the C++ reference at tuikit_engine/src/pipeline/call/module/v3_call/.

Install

pnpm add call-engine-wx @tencentcloud/lite-chat
# only if you'll call getTRTCCloudInstance() / video features
pnpm add @tencentcloud/trtc-cloud-wx

@tencentcloud/trtc-cloud-wx is declared as an optional peer-dependency. If your use case is "just login / receive offline invites", you do not need to install it.

Quickstart

import TUICallEngine, { TUICallEvent } from 'call-engine-wx';

TUICallEngine.once('ready', async () => {
  const engine = TUICallEngine.createInstance({ SDKAppID });

  engine.on(TUICallEvent.SDK_READY, () => {
    console.log('SDK ready');
  });
  engine.on(TUICallEvent.KICKED_OUT, () => { /* ... */ });
  engine.on(TUICallEvent.onUserSigExpired, () => { /* refresh userSig */ });

  await engine.login({ userID, userSig });
});

With an existing lite-chat instance

import TencentCloudChat from '@tencentcloud/lite-chat';
import TUICallEngine from 'call-engine-wx';

const tim = TencentCloudChat.create({ SDKAppID });
const engine = TUICallEngine.createInstance({ SDKAppID, tim });
await engine.login({ userID, userSig });

API (already implemented)

| Method | Notes | | --- | --- | | TUICallEngine.createInstance(options) | Singleton create / reuse. | | TUICallEngine.once('ready', fn) | Fires on next microtask (no WASM to wait for). | | engine.login({ userID, userSig }) | Calls tim.login, emits SDK_READY. | | engine.logout() | Calls tim.logout. | | engine.destroyInstance() | Logout + unbind + drop singleton. | | engine.on / off / once | Local event bus. | | engine.getTim() | Underlying lite-chat instance. | | engine.getTRTCCloudInstance() | Lazy TRTCCloud.createInstance(). | | engine.setLogLevel(level) | Forwarded to lite-chat. | | engine.calls(params) | Multi-party call. Enters the TRTC room and sends call_engine_srv.start_call. See below. |

engine.calls(params)

const { inviteId, roomId, callResultList } = await engine.calls({
  inviteeList: ['userA', 'userB'],
  mediaType: CallMediaType.VIDEO,    // or CallMediaType.AUDIO
  groupID: 'optional-group-id',
  // roomID: 12345678,               // optional, auto-generated if absent
  timeout: 30,                       // seconds
  userData: 'free-form string',
  // offlinePushInfo: { ... }        // optional, see ICallsParams type
});

The return shape:

| Field | Type | Notes | | --- | --- | --- | | inviteId | string | Server-issued call_id; needed for cancel / accept / hangup. | | roomId | { intRoomId, strRoomId } | The TRTC room actually joined. | | callResultList | Array | Per-callee outcome (SUCCESS / INVITED / LINE_BUSY). |

Side effects emitted on the engine event bus:

• onUserJoin(userId) for each invitee with INVITED (1)
• onUserInviting(userId) for each invitee with SUCCESS (0)
• onUserLineBusy(userId) for each invitee with LINE_BUSY (2)
• onCallNotConnected({ callInfo, userId, reason: LINE_BUSY }) if every invitee returned busy. The TRTC room is left automatically in that case.

If start_call fails (transport error or backend rejection), the engine leaves the TRTC room and rejects the promise with { code, message }.

API (not yet implemented)

call / accept / reject / hangup / inviteUser / switchCallMediaType / openCamera / closeCamera / openMicrophone / closeMicrophone / startRemoteView / stopRemoteView / ...

These will be added on top of the same lite-chat session, using the backend call_engine_srv SSO protocol — no WASM involved.