[NOWEB] Delete group not implemented (501)

[omernesh]

Describe the bug

DELETE /api/{session}/groups/{id} returns 501 "Not Implemented" on the NOWEB engine.

WAHA Version: 2026.4.2
Engine: NOWEB
Tier: PLUS

To Reproduce

1. Create a group: POST /api/{session}/groups with {"subject": "Test Group", "participants": []}
2. Attempt to delete: DELETE /api/{session}/groups/{groupId}
3. Response: {"message":"The method is not implemented by 'NOWEB' engine.","error":"Not Implemented","statusCode":501}

Expected behavior

The group should be deleted (or at minimum, all participants removed and the group archived), matching the behavior on the WEBJS engine.

Additional context

WhatsApp allows group admins to delete groups. The endpoint is documented in the OpenAPI spec and works on WEBJS, but returns 501 on NOWEB. As a workaround we use the /leave endpoint, but that only removes the bot — it doesn't delete the group.

[omernesh]

+1 — this is a real gap for us. We run production WhatsApp automation on NOWEB and can't offer group deletion to our users because NOWEB returns 501 for group delete (leaving a group works, deleting doesn't). Would really value DELETE group support on NOWEB. Thanks for the great work on WAHA.

[omernesh]

We dug into this on NOWEB and found the actual blocker is narrower than "delete group not implemented" — and it's fixable with a very small engine addition.

Why a native deleteGroup can't exist on NOWEB: the shipped Baileys socket exposes no group-destroy primitive (Socket/groups: groupCreate, groupLeave, groupUpdateSubject, groupParticipantsUpdate, invite ops… — no delete), which matches the WhatsApp multi-device protocol itself: every official client implements "delete group" client-side as remove participants → leave → delete the chat.

The real gap: the first two steps already work on NOWEB (removeParticipants, /leave). The missing piece is DELETE /api/{session}/chats/{chatId} — deleteChat is only implemented for the browser engines (e.g. WEBJS chat.delete()), while NOWEB falls through to the base-class NotImplementedByEngineError (session.abc). So after kick+leave, the dead group lingers in the chat list forever.

Proposed fix — implement NOWEB deleteChat with the exact idiom chatsPutArchive already uses (chatModify is a first-class Baileys primitive and delete is one of its supported modifications):

// src/core/engines/noweb/session.noweb.core.ts
override async deleteChat(chatId: string) {
  const jid = toJID(chatId);
  const messages = await this.store.getMessagesByJid(jid, {}, { limit: 1 });
  return await this.sock.chatModify(
    { delete: true, lastMessages: messages },
    jid,
  );
}

That's the whole change — same toJID + lastMessages plumbing as the archive/unarchive/unread implementations three methods up, no new routes or webhooks.

With this in place, "delete group" on NOWEB becomes fully achievable for API consumers as removeParticipants → leave → deleteChat (that's what we now do in our application layer, with the deleteChat step tolerated as 501 until this lands). If you're open to it I'm happy to send this as a PR.

One practical note for anyone orchestrating the workaround meanwhile: NOWEB group mutations (create/add/remove participants) routinely take ~90s server-side, so client timeouts below that will abort operations that would have succeeded.