Azure Function Webhook 请求内容异常处理与健壮性优化

import os
import base64
import json
import jwt
from hashlib import md5
from datetime import datetime, timedelta
import azure.functions as func
import logging
import requests
from http.client import IncompleteRead # 导入 IncompleteRead 异常

def webhook_decoder_baas(req: func.HttpRequest) -> func.HttpResponse:
    try:
        # ... (省略私钥、公钥等初始化代码)
        private_key = os.environ["private_key_baas"]
        private_key_baas = base64.b64decode(private_key).decode("utf-8")
        qi_public_key = '''-----BEGIN PUBLIC KEY-----
        ... :)
        -----END PUBLIC KEY-----'''

        authorization = req.headers.get("AUTHORIZATION")

        if not authorization:
            logging.error("AUTHORIZATION header not provided.")
            return func.HttpResponse("AUTHORIZATION header not provided.", status_code=400)

        # 优化请求体处理部分
        try:
            body = req.get_body() # 获取原始字节流
            if body is None or len(body) == 0:
                logging.error("Empty or missing request body.")
                return func.HttpResponse("Empty or missing request body.", status_code=400)

            body_json = json.loads(body) # 显式解析 JSON
        except ValueError as json_error:
            # 捕获 JSON 解析错误
            logging.error(f"Error parsing JSON: {str(json_error)}")
            return func.HttpResponse("Error parsing JSON", status_code=400)
        except IncompleteRead as incomplete_read_error:
            # 捕获请求内容不完整错误
            logging.error(f"Incomplete read error: {str(incomplete_read_error)}")
            return func.HttpResponse("Incomplete read error", status_code=400)

        # JWT 解码和断言验证
        decoded_header = jwt.decode(token=authorization, key=qi_public_key)

        # 使用断言进行数据验证，并提供清晰的错误信息
        assert decoded_header.get("method") == "POST", "Error in the sending method, a different method than POST was used."
        assert decoded_header.get("payload_md5") == md5(json.dumps(body_json).encode()).hexdigest(), "Payload hash does not match the expected one."
        assert (datetime.utcnow() - timedelta(minutes=5)) < datetime.strptime(decoded_header.get("timestamp"), "%Y-%m-%dT%H:%M:%S.%fZ") < (datetime.utcnow() + timedelta(minutes=5)), "Error in sending timestamp, outside the 10-minute limit."

        # ... (原有业务逻辑：数据提取、创建新 JSON、发送 POST 请求等)
        payload_string = json.dumps(body_json)
        objeto_payload = json.loads(payload_string) # 这一步实际上是多余的，body_json已经是Python对象

        if (
            objeto_payload.get("webhook_type") == "bank_slip.status_change" and 
            (objeto_payload.get("status") == "payment_notice" or objeto_payload.get("status") == "notary_office_payment_notice")
        ):
            bank_slip_key = objeto_payload.get("data", {}).get("bank_slip_key")
            paid_amount = objeto_payload.get("data", {}).get("paid_amount")

            payload_output = {
                key: objeto_payload[key] for key in ["status"]
            }
            payload_output['Paid amount'] = paid_amount
            payload_output['Query key of the title'] = bank_slip_key

            url = "https://nerowebhooks.azurewebsites.net/api/information/send"
            token = jwt.encode(payload_output, private_key_baas, algorithm='ES512')
            headers = {'SIGNATURE': token}
            response = requests.post(url, headers=headers, json=payload_output)

            logging.info(f"Received webhook: {payload_output}")
            return func.HttpResponse("Webhook received successfully!", status_code=200)
        else:
            logging.info("Webhook received successfully, but it won't be handled at the moment!")
            return func.HttpResponse("Webhook received successfully, but it won't be handled at the moment!")

    # 集中处理 JWT 相关的错误
    except jwt.JWTError as jwt_error:
        logging.error(f"Token error: {str(jwt_error)}")
        return func.HttpResponse(f"Token error: {str(jwt_error)}", status_code=400)
    # 集中处理断言错误
    except AssertionError as assertion_error:
        logging.error(f"Assertion error: {str(assertion_error)}")
        return func.HttpResponse(str(assertion_error), status_code=400)
    # 捕获所有其他未预料的内部错误
    except Exception as e:
        logging.error(f"Internal error while processing the webhook: {str(e)}")
        return func.HttpResponse(f"Internal error while processing the webhook: {str(e)}", status_code=500)