[Twilio+Python] 認証コードを読み上げる音声通話認証の実装

mkdir twilio-voice-auth-python
cd twilio-voice-auth-python
python -m venv venv
source venv/bin/activate  # Windows の場合は venv\Scripts\activate

pip install Flask twilio python-dotenv

TWILIO_ACCOUNT_SID=ACXXXXXXXXXXXXXXXXXXXXXXXXXXXX
TWILIO_AUTH_TOKEN=your_auth_token
TWILIO_CALLER_ID=+81XXXXXXXXXX

# app.py
from flask import Flask, request, Response
from twilio.rest import Client
from dotenv import load_dotenv
import os
import random
import threading
import json

load_dotenv()

app = Flask(__name__)
client = Client(os.getenv("TWILIO_ACCOUNT_SID"), os.getenv("TWILIO_AUTH_TOKEN"))

# メモリ上にコードを保持（本番では Redis 推奨）
code_storage = {}

def delete_code(phone):
    code_storage.pop(phone, None)

@app.route("/start-call", methods=["POST"])
def start_call():
    phone = request.json.get("phoneNumber")
    code = str(random.randint(100000, 999999))
    code_storage[phone] = code

    # 5分後に自動削除
    threading.Timer(300, delete_code, [phone]).start()

    spaced = ", ".join(code)
    twiml = f"""
    <Response>
      <Say language="ja-JP" voice="alice">こんにちは。あなたの認証コードは、</Say>
      <Pause length="1"/>
      <Say language="ja-JP" voice="alice">{spaced}</Say>
      <Say language="ja-JP" voice="alice">です。</Say>
    </Response>
    """

    try:
        call = client.calls.create(
            to=phone,
            from_=os.getenv("TWILIO_CALLER_ID"),
            twiml=twiml
        )
        result = {
            "success": True,
            "message": "通話を発信しました。",
            "callSid": call.sid
            # "code": code  # ← デバッグ時は表示してOK
        }
        return Response(json.dumps(result, ensure_ascii=False), mimetype="application/json")
    except Exception as e:
        result = {
            "success": False,
            "message": "通話の発信に失敗しました。",
            "error": str(e)
        }
        return Response(json.dumps(result, ensure_ascii=False), mimetype="application/json"), 500

@app.route("/verify-code", methods=["POST"])
def verify_code():
    phone = request.json.get("phoneNumber")
    input_code = request.json.get("code")
    expected = code_storage.get(phone)

    if not expected:
        result = {"success": False, "message": "コードが期限切れまたは存在しません。"}
        return Response(json.dumps(result, ensure_ascii=False), mimetype="application/json"), 400

    if input_code == expected:
        code_storage.pop(phone, None)
        result = {"success": True, "message": "認証成功"}
        return Response(json.dumps(result, ensure_ascii=False), mimetype="application/json")
    else:
        result = {"success": False, "message": "認証コードが一致しません。"}
        return Response(json.dumps(result, ensure_ascii=False), mimetype="application/json"), 401

if __name__ == "__main__":
    app.run(port=3000)

curl -X POST http://localhost:3000/verify-code \
  -H "Content-Type: application/json" \
  -d '{"phoneNumber": "+81XXXXXXXXXX", "code": "読み上げられた6桁"}'

{ "success": true, "message": "認証成功" }