whapd

What it is

In plain terms, whapd is the connector that plugs WhatsApp into arizuko, so the agent can read and reply in WhatsApp chats and groups.

whapd is the WhatsApp channel adapter. It speaks WhatsApp Web through the Baileys socket library (TypeScript / Node, the only non-Go adapter in the core), posts inbound to routd, and sends outbound through the same socket. JID prefix is whatsapp:; per-conversation JIDs are whatsapp:<jid> where jid is the Baileys-native form (phone-number@s.whatsapp.net or group-id@g.us).

Why it exists

WhatsApp has no usable consumer API. The official Cloud API is partner-gated and quota-limited; everyone else uses a WhatsApp Web client. Baileys has no Go port, so whapd lives in TypeScript. Pairing credentials persist in $WHATSAPP_AUTH_DIR/creds.json with an atomic .bak rotation; a fresh install requires pairing.

How it fits

WhatsApp (web.whatsapp.com socket)
        |  Baileys multi-device socket
        v
      whapd     (LISTEN_ADDR=:8080, Node runtime)
        |  POST /v1/messages    (signed by CHANNEL_SECRET)
        v
      routd
        |  POST /send           (callback to whapd)
        v
      whapd     (sock.sendMessage / reactMessage / delete)
        |
        v
      WhatsApp

Wired verbs (whapd/src/server.ts): send (sendMessage(jid, {text}), honours reply_to via Baileys quoted), send_file (image / video / audio / document by mime sniff), typing (composing / paused presence with refresher), like (reaction; emoji selectable via reaction field, default 👍), edit (own messages, 15-min window), delete (own-message redaction), forward (best-effort — synthesizes forwarded text since Baileys only gives source_msg_id). quote, repost, dislike, post are 501-with-hint — dislike redirects to like(reaction='👎').

No fetch_history: Baileys’ history sync is unreliable across the LID/JID translation Meta introduced in 2024; the gateway falls back to its local cache.

Pairing

Two paths, both token-less:

QR code — the default. whapd prints a QR ascii to the container log; scan it from WhatsApp on the phone (Settings → Linked devices → Link a device).
Pairing code — --pair <phone> on the binary, or the self-service flow at /dash/channels/whatsapp/pair (shipped v0.40.2). The operator enters the bot phone number; whapd prints an 8-character code; the operator types it on the phone instead of scanning a QR. Useful for headless deploys.

Lose creds.json and the device is unlinked — re-pair. whapd backs up to creds.json.bak on every save and recovers from it on a crash. The outbound queue is persisted to disk and auto-resumes on reconnect.

Standalone usage

export ROUTER_URL=http://routd:8080
export CHANNEL_SECRET=$(grep ^CHANNEL_SECRET .env | cut -d= -f2)
export LISTEN_ADDR=:8080
export WHATSAPP_AUTH_DIR=/srv/data/store/whatsapp-auth
export DATA_DIR=/srv/data/arizuko_demo
node dist/main.js

GET /health returns 503 while waiting for QR / pairing-code scan and while the Baileys socket is disconnected. The container log carries the QR; sudo docker logs arizuko-<inst>-whapd-1 on the host.

Go deeper

components/channels — cross-adapter verb matrix.
whapd/README.md — verb table, file map, edit/delete window.