Webhookでイベントに対応する

{  "event": "endpoint.verification",  "nonce": "9f2c1e642b1a4b0e9f1a2c7d5e8a1b3c",  "timestamp": "2026-08-25T14:32:10Z"}

import base64import hashlibimport hmacimport os from flask import Flask, abort, request app = Flask(__name__)SECRET = os.environ["LISTINGSAPI_WEBHOOK_SECRET"].encode()  def signature_is_valid(raw_body: bytes, header: str | None) -> bool:  digest = hmac.new(SECRET, raw_body, hashlib.sha256).digest()  expected = "sha256=" + base64.b64encode(digest).decode()  return hmac.compare_digest(header or "", expected)  @app.post("/webhooks/listingsapi")def webhooks():  raw = request.get_data()  # raw bytes, exactly as received  if not signature_is_valid(raw, request.headers.get("X-ListingsAPI-Signature")):      abort(401)   body = request.get_json(silent=True) or {}   # One-time handshake: hex digest of the nonce, not the body.  if body.get("event") == "endpoint.verification":      return hmac.new(SECRET, body["nonce"].encode(), hashlib.sha256).hexdigest(), 200   # Real event: durable write first, then acknowledge. Swap for your queue.  inbox.put(raw)  # must be committed before the 200 goes out  return {"received": True}, 200

import crypto from 'crypto';import express from 'express'; const app = express();const SECRET = process.env.LISTINGSAPI_WEBHOOK_SECRET as string; // express.raw keeps req.body as the untouched Buffer the HMAC covers.app.post('/webhooks/listingsapi', express.raw({ type: '*/*' }), async (req, res) => {const raw: Buffer = req.body;const digest = crypto.createHmac('sha256', SECRET).update(raw).digest('base64');const expected = Buffer.from('sha256=' + digest);const given = Buffer.from(req.get('X-ListingsAPI-Signature') ?? '');if (given.length !== expected.length || !crypto.timingSafeEqual(given, expected)) {  return res.status(401).send('bad signature');} const body = JSON.parse(raw.toString('utf8')); // One-time handshake: hex digest of the nonce, not the body.if (body.event === 'endpoint.verification') {  const answer = crypto.createHmac('sha256', SECRET).update(body.nonce).digest('hex');  return res.status(200).send(answer);} // Real event: durable write first, then acknowledge. Swap for your queue.await inbox.put(raw); // must be committed before the 200 goes outreturn res.status(200).json({ received: true });});

{  "event": "connection.location_connected",  "timestamp": "2026-08-25T14:32:10Z",  "account_id": 11073,  "location_id": "279381",  "data": { "platform": "google", "connected_account_id": "ba03bc4b-9f8c-4d3b-8e93-9628034c63cc" }}

import hashlibimport time SEEN: dict[str, float] = {}  # use Redis with a TTL in productionWINDOW_SECONDS = 600 def is_duplicate(raw_body: bytes) -> bool:  key = hashlib.sha256(raw_body).hexdigest()  now = time.time()  for k, seen_at in list(SEEN.items()):      if now - seen_at > WINDOW_SECONDS:          del SEEN[k]  if key in SEEN:      return True  SEEN[key] = now  return False