telephony.incoming / web.incoming

import hashlib
import hmac
import json
import os

from fastapi import FastAPI, HTTPException, Request

app = FastAPI()
WEBHOOK_SECRET = os.environ["THUNDERPHONE_WEBHOOK_SECRET"]

def verify(body: bytes, signature: str) -> bool:
    expected = hmac.new(WEBHOOK_SECRET.encode(), body, hashlib.sha256).hexdigest()
    return hmac.compare_digest(expected, signature or "")

@app.post("/thunderphone-webhook")
async def webhook(request: Request):
    body = await request.body()
    if not verify(body, request.headers.get("X-ThunderPhone-Signature", "")):
        raise HTTPException(status_code=401)

    event = json.loads(body)
    if event["type"] == "telephony.incoming":
        caller = event["data"]["from_number"]
        prompt = (
            "Greet the caller as a San Francisco local…"
            if caller.startswith("+1415")
            else "You are a friendly customer support agent…"
        )
        return {
            "prompt": prompt,
            "voice": "john",
            "product": "spark",
        }
    if event["type"] == "web.incoming":
        return {
            "prompt": "You are the website's helpful voice assistant…",
            "voice": "john",
            "product": "spark",
        }
    return {}

import crypto from "node:crypto";
import express from "express";

const app = express();
const SECRET = process.env.THUNDERPHONE_WEBHOOK_SECRET;

function verify(body, signature) {
  const expected = crypto
    .createHmac("sha256", SECRET)
    .update(body)
    .digest("hex");
  return signature &&
    crypto.timingSafeEqual(Buffer.from(expected), Buffer.from(signature));
}

app.post(
  "/thunderphone-webhook",
  express.raw({ type: "application/json" }),
  (req, res) => {
    if (!verify(req.body, req.header("X-ThunderPhone-Signature"))) {
      return res.sendStatus(401);
    }
    const event = JSON.parse(req.body.toString("utf8"));

    if (event.type === "telephony.incoming" || event.type === "web.incoming") {
      const caller = event.data.from_number || "web";
      const prompt = caller.startsWith("+1415")
        ? "Greet the caller as a San Francisco local…"
        : "You are a friendly customer support agent…";
      return res.json({
        prompt,
        voice: "john",
        product: "spark",
      });
    }
    res.json({});
  },
);