feat(platform): standalone HTTP Bot adapter (server-to-server) (#2274)

* docs(platform): add HTTP Bot adapter design (RFC) Standalone server-to-server HTTP adapter for driving a pipeline from external systems (LangBot Space ticketing et al). Inbound via the existing unified webhook route; outbound via signed callback POSTs. Preserves pipeline-native N->1 aggregation and 1->M multi-reply without a long-lived WebSocket. No core changes required (router/aggregator/pipeline untouched). * feat(platform): add standalone HTTP Bot adapter A first-class, vendor-neutral message-platform adapter (http_bot) for server-to-server integrations (LangBot Space ticketing et al). Drives a pipeline over plain HTTP with no long-lived connection: - Inbound: signed POST to the existing unified webhook route /bots/<uuid>, carrying a caller-defined session_id mapped to the LangBot launcher id via get_launcher_id -> per-session isolation. Preserves pipeline-native N->1 aggregation for free. - Outbound: each reply_message / reply_message_chunk becomes one signed callback POST to the config-only callback_url, delivered in per-session sequence order with retry/backoff -> 1->M multi-reply. - Sub-paths: /reset (drop a session) and /sync (block for the collapsed reply). - Auth: symmetric HMAC-SHA256 both directions (timestamp + replay window), no JWT/Turnstile, no socket. Decisions: callback URL is config-only (SSRF closed); reset + sync shipped; Python + TS reference clients shipped (signing verified byte-identical 3-way). No core changes: the unified webhook router, aggregator, query pool and pipeline are untouched. Adapter is auto-discovered from platform/sources/. Adds: src/langbot/pkg/platform/sources/http_bot.{py,yaml,svg} src/langbot/pkg/platform/sources/http_bot_signing.py docs/platforms/http-bot.md, docs/http-bot-openapi.json examples/http-bot/{client.py,client.ts,README.md} Updates docs/HTTP_BOT_ADAPTER_DESIGN.md (status: implemented). * docs(examples): add interactive HTTP Bot playground (browser debug console) A single-file aiohttp web app (examples/http-bot/playground.py) that lets you chat with a RUNNING http_bot bot from the browser and watch the protocol live: signed inbound POST -> 202 ack -> 1->M signed callbacks streamed back via SSE, with a debug panel showing the signature, HTTP status, and per-callback sequence/verification. Light LangBot-styled UI. On startup it reads the API key + http_bot bot from data/langbot.db and points the bot's callback_url + secrets back at itself via the LangBot API (live reload, no restart). README updated with a playground section. * docs(examples): add Chinese README for http-bot reference clients * style(platform): use </> code icon for http_bot adapter logo * docs(examples): point http-bot guide links to docs.langbot.app * style(platform): make http_bot icon a transparent monochrome </> so WebUI tints it like other adapters * Revert to colorful </> badge for http_bot icon (WebUI renders it as-is)
2026-06-22 13:34:24 +00:00 · 2026-06-22 13:38:00 +08:00
parent 74a18191dd
commit 144bec371c
12 changed files with 2580 additions and 0 deletions
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+#!/usr/bin/env python3
+"""LangBot HTTP Bot adapter — reference client (Python).
+
+Two things in one file:
+
+1. ``push()`` / ``push_sync()`` — send a message into a LangBot ``http_bot`` bot.
+2. A tiny Flask callback receiver that verifies signatures and prints replies,
+   so you can watch N->1 aggregation and 1->M multi-reply working live.
+
+Usage
+-----
+    pip install flask requests
+
+    # Terminal 1 — start the callback receiver (this is your callback_url):
+    python client.py serve --port 8900 --secret SHARED_SECRET
+
+    # Terminal 2 — push a message (async; reply lands on the receiver):
+    python client.py push \
+        --url   https://your-langbot/bots/<BOT_UUID> \
+        --secret SHARED_SECRET \
+        --session ticket-10293 \
+        --text "Export keeps failing on the dashboard."
+
+    # Or push and block for the collapsed reply (sync convenience mode):
+    python client.py sync --url https://your-langbot/bots/<BOT_UUID> \
+        --secret SHARED_SECRET --session ticket-10293 --text "hi"
+
+The signing scheme is HMAC-SHA256 over ``"{timestamp}." + raw_body``; see
+``sign()`` below — it is intentionally tiny and easy to port.
+"""
+
+from __future__ import annotations
+
+import argparse
+import hashlib
+import hmac
+import json
+import sys
+import time
+import uuid
+
+HEADER_TIMESTAMP = 'X-LB-Timestamp'
+HEADER_SIGNATURE = 'X-LB-Signature'
+HEADER_IDEMPOTENCY = 'X-LB-Idempotency-Key'
+REPLAY_WINDOW = 300
+
+
+def sign(secret: str, body: bytes, timestamp: int | None = None) -> tuple[str, str]:
+    """Return (timestamp, signature) for *body*."""
+    ts = str(timestamp if timestamp is not None else int(time.time()))
+    mac = hmac.new(secret.encode(), f'{ts}.'.encode() + body, hashlib.sha256)
+    return ts, 'sha256=' + mac.hexdigest()
+
+
+def verify(secret: str, body: bytes, timestamp: str | None, signature: str | None) -> bool:
+    """Verify an inbound signature (used by the callback receiver)."""
+    if not timestamp or not signature:
+        return False
+    try:
+        if abs(int(time.time()) - int(float(timestamp))) > REPLAY_WINDOW:
+            return False
+    except ValueError:
+        return False
+    _, expected = sign(secret, body, int(float(timestamp)))
+    return hmac.compare_digest(expected, signature)
+
+
+def _post(url: str, secret: str, payload: dict, idempotency: bool = True):
+    import requests
+
+    body = json.dumps(payload, ensure_ascii=False).encode()
+    ts, sig = sign(secret, body)
+    headers = {
+        'Content-Type': 'application/json',
+        HEADER_TIMESTAMP: ts,
+        HEADER_SIGNATURE: sig,
+    }
+    if idempotency:
+        headers[HEADER_IDEMPOTENCY] = uuid.uuid4().hex
+    resp = requests.post(url, data=body, headers=headers, timeout=30)
+    print(f'-> {resp.status_code} {resp.text}')
+    return resp
+
+
+def push(url: str, secret: str, session: str, text: str, session_type: str = 'person'):
+    """Fire-and-collect: returns 202 immediately; reply arrives on your callback."""
+    payload = {
+        'session_id': session,
+        'session_type': session_type,
+        'message': [{'type': 'Plain', 'text': text}],
+    }
+    return _post(url.rstrip('/'), secret, payload)
+
+
+def push_sync(url: str, secret: str, session: str, text: str, session_type: str = 'person'):
+    """Blocking convenience: POST to /sync and get the collapsed reply back."""
+    payload = {
+        'session_id': session,
+        'session_type': session_type,
+        'message': [{'type': 'Plain', 'text': text}],
+    }
+    resp = _post(url.rstrip('/') + '/sync', secret, payload, idempotency=False)
+    return resp
+
+
+def reset(url: str, secret: str, session: str, session_type: str = 'person'):
+    """Reset a session's conversation (next message starts fresh)."""
+    payload = {'session_id': session, 'session_type': session_type}
+    return _post(url.rstrip('/') + '/reset', secret, payload, idempotency=False)
+
+
+def serve(port: int, secret: str):
+    """Run a callback receiver that verifies signatures and prints replies."""
+    from flask import Flask, request
+
+    app = Flask(__name__)
+
+    @app.route('/', methods=['POST'])
+    def recv():
+        raw = request.get_data()
+        ok = verify(secret, raw, request.headers.get(HEADER_TIMESTAMP), request.headers.get(HEADER_SIGNATURE))
+        if not ok:
+            print('!! signature verification FAILED — rejecting')
+            return {'error': 'bad signature'}, 401
+        data = json.loads(raw)
+        text_parts = [c.get('text', '') for c in data.get('message', []) if c.get('type') == 'Plain']
+        marker = 'FINAL' if data.get('is_final') else 'part '
+        print(
+            f'[{marker}] session={data["session_id"]} seq={data["sequence"]} '
+            f'reply_to={data.get("reply_to")}: {" ".join(text_parts)}'
+        )
+        return {'ok': True}
+
+    print(f'callback receiver listening on http://0.0.0.0:{port}/  (Ctrl-C to stop)')
+    app.run(host='0.0.0.0', port=port)
+
+
+def main(argv=None):
+    p = argparse.ArgumentParser(description='LangBot HTTP Bot reference client')
+    sub = p.add_subparsers(dest='cmd', required=True)
+
+    sp = sub.add_parser('serve', help='run the callback receiver')
+    sp.add_argument('--port', type=int, default=8900)
+    sp.add_argument('--secret', required=True)
+
+    for name in ('push', 'sync', 'reset'):
+        c = sub.add_parser(name)
+        c.add_argument('--url', required=True, help='https://host/bots/<BOT_UUID>')
+        c.add_argument('--secret', required=True)
+        c.add_argument('--session', required=True)
+        c.add_argument('--session-type', default='person', choices=['person', 'group'])
+        if name != 'reset':
+            c.add_argument('--text', required=True)
+
+    args = p.parse_args(argv)
+    if args.cmd == 'serve':
+        serve(args.port, args.secret)
+    elif args.cmd == 'push':
+        push(args.url, args.secret, args.session, args.text, args.session_type)
+    elif args.cmd == 'sync':
+        push_sync(args.url, args.secret, args.session, args.text, args.session_type)
+    elif args.cmd == 'reset':
+        reset(args.url, args.secret, args.session, args.session_type)
+
+
+if __name__ == '__main__':
+    sys.exit(main())