TDLib client closes after successful login and keepOnline crashes the server

[shafed]

After successfully authenticating with Telegram, the backend reaches the ready state, but shortly afterwards the underlying tdl client becomes closed.

The keepOnline timer in src/client.ts still tries to call client.invoke(...) on the closed client, which crashes the Node.js server with:

Error: A closed client cannot be reused, create a new client

In my case, :Tg also reports that no chats were found before the backend eventually crashes.

To Reproduce

Steps to reproduce the behavior:

1. Run :Tg, or start the backend manually:

   cd ~/.local/share/nvim/lazy/telegram.nvim
   npx tsx src/server.ts

2. Complete Telegram authentication (phone number, code, and 2FA password if required).

3. Verify that the backend reports:

   TDLib client ready
   

   and:

   curl -s http://localhost:8080/health | jq

   returns:

   {
     "ready": true,
     "auth": {
       "state": "ready",
       "error": null,
       "canInput": false
     }
   }

4. Wait for the keepOnline timer to run.

5. The backend crashes with:

   Error: A closed client cannot be reused, create a new client
       at Client._send (.../node_modules/tdl/dist/client.js:481:19)
       at Client.invoke (.../node_modules/tdl/dist/client.js:228:18)
       at Timeout.keepOnline (.../src/client.ts:147:21)
   

6. When opening Telegram from Neovim, I also get No chats found.

Expected behavior

After successful authentication, the TDLib client should remain usable and :Tg should load the user's chats.

If the TDLib client is closed for some reason, the keepOnline timer should stop instead of calling invoke() on a closed client and crashing the backend.

Ideally, the backend should also log why the TDLib client was closed.

Screenshots / Logs

Backend startup:

TDLib library: /usr/lib/libtdjson.so.1.8.64
HTTP server: http://localhost:8080
WebSocket server: ws://localhost:8081
TDLib version: 1.8.64

After authentication:

{
  "ready": true,
  "auth": {
    "state": "ready",
    "hint": "",
    "error": null,
    "canInput": false
  }
}

Some TDLib messages printed before the crash:

[AttachMenuManager] Have no colors for attachment menu bot icon
[AttachMenuManager] Have icon ... with name android_active_animated
[StickersManager] Trending sticker sets hash mismatch

Crash:

/home/shafed/.local/share/nvim/lazy/telegram.nvim/node_modules/tdl/dist/client.js:481
    throw new Error('A closed client cannot be reused, create a new client');
    ^

Error: A closed client cannot be reused, create a new client
    at Client._send (/home/shafed/.local/share/nvim/lazy/telegram.nvim/node_modules/tdl/dist/client.js:481:19)
    at Client.invoke (/home/shafed/.local/share/nvim/lazy/telegram.nvim/node_modules/tdl/dist/client.js:228:18)
    at Timeout.keepOnline (/home/shafed/.local/share/nvim/lazy/telegram.nvim/src/client.ts:147:21)
    at listOnTimeout (node:internal/timers:685:17)
    at process.processTimers (node:internal/timers:618:7)

Node.js v26.8.1

Environment (please complete):

• OS: Arch Linux
• Neovim version: 0.11.3
• Node.js version: 26.8.1
• TDLib version: 1.8.64
• telegram.nvim version: current main

Additional context

The backend can successfully connect to TDLib and complete authentication. /health reports ready: true before the crash, so the failure happens after authentication.

The immediate crash appears to come from the keepOnline timer continuing to call:

this.client.invoke({
  _: 'setOption',
  name: 'online',
  value: { _: 'optionValueBoolean', value: true }
})

after the underlying tdl client has already been closed.

It may be useful to listen for the client's close event, set _ready = false, cancel _keepOnlineTimer, and log the reason/state transition. This would prevent the secondary crash and make it easier to diagnose why the client is closing in the first place.

[ChuYanLon]

Okay, I have been busy with other things lately. I will reproduce this problem as soon as possible and solve it. Please keep an eye on project changes.