twilio-communications

Twilio 通信

模式

SMS 发送模式

使用 Twilio 发送 SMS 消息的基本模式。 涵盖核心内容：电话号码格式、消息投递 和投递状态回调。

关键注意事项：

• 电话号码必须采用 E.164 格式（+1234567890）
• 默认速率限制：每秒 80 条消息（MPS）
• 超过 160 个字符的消息会被拆分（费用也会更高）
• 运营商过滤可能会拦截消息（尤其是发送至美国号码时）

适用场景：['向用户发送通知', '事务性消息（订单确认、发货通知）', '警报和提醒']

from twilio.rest import Client
from twilio.base.exceptions import TwilioRestException
import os
import re

class TwilioSMS:
    """
    SMS sending with proper error handling and validation.
    """

    def __init__(self):
        self.client = Client(
            os.environ["TWILIO_ACCOUNT_SID"],
            os.environ["TWILIO_AUTH_TOKEN"]
        )
        self.from_number = os.environ["TWILIO_PHONE_NUMBER"]

    def validate_e164(self, phone: str) -> bool:
        """Validate phone number is in E.164 format."""
        pattern = r'^\+[1-9]\d{1,14}$'
        return bool(re.match(pattern, phone))

    def send_sms(
        self,
        to: str,
        body: str,
        status_callback: str = None
    ) -> dict:
        """
        Send an SMS message.

        Args:
            to: Recipient phone number in E.164 format
            body: Message text (160 chars = 1 segment)
            status_callback: URL for delivery status webhooks

        Returns:
            Message SID and status
        """
        # Validate phone number format
        if not self.validate_e164(to):
            return {
                "success": False,
                "error": "Phone number must be in E.164 format (+1234567890)"
            }

        # Check message length (warn about segmentation)
        segment_count = (len(body) + 159) // 160
        if segment_count > 1:
            print(f"Warning: Message will be sent as {segment_count} segments")

        try:
            message = self.client.messages.create(
                to=to,
                from_=self.from_number,
                body=body,
                status_callback=status_callback
            )

            return {
                "success": True,
                "message_sid": message.sid,
                "status": message.status,
                "segments": segment_count
            }

        except TwilioRestException as e:
            return self._handle_error(e)

    def _handle_error(self, error: Twilio

Twilio Verify 模式（2FA/OTP）

使用 Twilio Verify 进行电话号码验证和 2FA。 负责处理验证码生成、发送、速率限制和欺诈防范。

相比自行实现 OTP 的主要优势：

• Twilio 负责管理验证码的生成和过期
• 内置欺诈防范（已帮助客户节省超过 8200 万美元，拦截 7.47 亿次尝试）
• 自动处理速率限制
• 支持多种渠道：SMS、语音、电子邮件、推送、WhatsApp

Google 发现，SMS 2FA 可拦截“100% 的自动化机器人、96% 的批量 网络钓鱼攻击，以及 76% 的定向攻击。”

适用场景：['用户注册时验证电话号码', '双重身份验证（2FA）', '密码重置验证', '高价值交易确认']

from twilio.rest import Client
from twilio.base.exceptions import TwilioRestException
import os
from enum import Enum
from typing import Optional

class VerifyChannel(Enum):
    SMS = "sms"
    CALL = "call"
    EMAIL = "email"
    WHATSAPP = "whatsapp"

class TwilioVerify:
    """
    Phone verification with Twilio Verify.
    Never store OTP codes - Twilio handles it.
    """

    def __init__(self, verify_service_sid: str = None):
        self.client = Client(
            os.environ["TWILIO_ACCOUNT_SID"],
            os.environ["TWILIO_AUTH_TOKEN"]
        )
        # Create a Verify Service in Twilio Console first
        self.service_sid = verify_service_sid or os.environ["TWILIO_VERIFY_SID"]

    def send_verification(
        self,
        to: str,
        channel: VerifyChannel = VerifyChannel.SMS,
        locale: str = "en"
    ) -> dict:
        """
        Send verification code to phone/email.

        Args:
            to: Phone number (E.164) or email
            channel: SMS, call, email, or whatsapp
            locale: Language code for message

        Returns:
            Verification status
        """
        try:
            verification = self.client.verify \
                .v2 \
                .services(self.service_sid) \
                .verifications \
                .create(
                    to=to,
                    channel=channel.value,
                    locale=locale
                )

            return {
                "success": True,
                "status": verification.status,  # "pending"
                "channel": channel.value,
                "valid": verification.valid
            }

        except TwilioRestException as e:
            return self._handle_verify_error(e)

    def check_verification(self, to: str, code: str) -> dict:
        """
        Check if verification code is correct.

        Args:
            to: Phone number or email that received code
            code: The code entered by user

        R

TwiML IVR 模式

使用 TwiML 构建交互式语音应答（IVR）系统。 TwiML（Twilio 标记语言）是一种 XML，用于告知 Twilio 接到来电时 应执行的操作。

核心 TwiML 动词：

• ：文本转语音
• ：播放音频文件
• ：收集按键或语音输入
• ：连接到另一个号码
• ：录制来电者的语音
• ：跳转到另一个 TwiML 端点

关键要点：Twilio 会向你的 webhook 发起 HTTP 请求，你返回 TwiML，Twilio 随即执行。由于此过程无状态，因此请使用 URL 参数或会话。

适用场景：['电话菜单系统（按 1 联系销售……）', '自动化客户支持', '带确认功能的预约提醒', '语音信箱系统']

from flask import Flask, request, Response
from twilio.twiml.voice_response import VoiceResponse, Gather
from twilio.request_validator import RequestValidator
import os

app = Flask(__name__)

def validate_twilio_request(f):
    """Decorator to validate requests are from Twilio."""
    def wrapper(*args, **kwargs):
        validator = RequestValidator(os.environ["TWILIO_AUTH_TOKEN"])

        # Get request details
        url = request.url
        params = request.form.to_dict()
        signature = request.headers.get("X-Twilio-Signature", "")

        if not validator.validate(url, params, signature):
            return "Invalid request", 403

        return f(*args, **kwargs)
    wrapper.__name__ = f.__name__
    return wrapper

@app.route("/voice/incoming", methods=["POST"])
@validate_twilio_request
def incoming_call():
    """Handle incoming call with IVR menu."""
    response = VoiceResponse()

    # Gather digits with timeout
    gather = Gather(
        num_digits=1,
        action="/voice/menu-selection",
        method="POST",
        timeout=5
    )
    gather.say(
        "Welcome to Acme Corp. "
        "Press 1 for sales. "
        "Press 2 for support. "
        "Press 3 to leave a message."
    )
    response.append(gather)

    # If no input, repeat
    response.redirect("/voice/incoming")

    return Response(str(response), mimetype="text/xml")

@app.route("/voice/menu-selection", methods=["POST"])
@validate_twilio_request
def menu_selection():
    """Route based on menu selection."""
    response = VoiceResponse()
    digit = request.form.get("Digits", "")

    if digit == "1":
        # Transfer to sales
        response.say("Connecting you to sales.")
        response.dial(os.environ["SALES_PHONE"])

    elif digit == "2":
        # Transfer to support
        response.say("Connecting you to support.")
        response.dial(os.environ["SUPPORT_PHONE"])

    elif digit == "3":
        # Voicemail
        response.say("Please leave a message after 

⚠️ 易踩坑之处

问题	严重程度	解决方案
问题	高	## 在数据库中跟踪退订状态
问题	中	## 为临时故障实现重试逻辑
问题	高	## 注册 A2P 10DLC（美国要求）
问题	严重	## 始终验证签名
问题	高	## 跟踪每位用户的会话窗口
问题	严重	## 切勿将凭据硬编码
问题	中	## 同时实现应用层速率限制