express.js 中嵌套异步函数中的错误处理

Question

我正在尝试编写一个微服务来向用户发送消息以验证他的电话号码。我正在研究微服务的一部分，其中向端点发送带有正确验证码的消息将触发将他的电话号码添加到 Firebase 的代码。但是，我想为用户满意度和调试目的提供良好的错误处理。我已经阅读了快速文档。起初，我只是在异步函数中抛出了一个错误，但我收到一个警告，即未处理的承诺异常将在未来以非零退出状态终止服务器。如果我使用 express 内置的 next 或 end 函数处理 catch 块中的错误，则代码不会完全终止（即使文档说它确实如此）。这会导致代码运行我的代码，向用户发送成功消息（覆盖我之前的错误消息）。即使我检查是否已发送标头，它仍然不会阻止成功响应覆盖我的消息。

如果您提供正确的信息，该代码将正常工作。重要的是在函数 validateVerificationCode 中抛出一个错误以记录并将正确的错误发送给客户端。当我触发导致以下错误的端点时，我会收到以下信息。

编辑： 以下是人们可能认为的可能解决方案。但是，在 express 中，每个抛出错误的异步函数也必须捕获错误。因此，firebase 查询必须捕获错误。

   public async verifyVerification(
    req: Request,
    res: Response,
    next: NextFunction
  ) {
    const { uid, verificationCode } = req.params;
    await this.validateVerificationCode(uid, verificationCode, res, next)
      .then(() => {
        console.log("Verifying user sms verification code complete");
      })
      .catch(error => {
        res.status(500);
        res.json({ error: error });
      });

    res.json({ success: "success" });

  }

  public async validateVerificationCode(
    uid: string,
    verificationCode: string,
    res: Response,
    next: NextFunction
  ) {
    const query = firestore.collectionGroup("PublicUser");

    const publicUserQuery = query.where("uid", "==", uid);
    publicUserQuery
      .limit(1)
      .get()
      .then((querySnapshot: any) => {
        querySnapshot.forEach((documentSnapshot: any) => {
          const smsVerificationInfo = documentSnapshot.get(
            "smsVerificationInfo"
          );

          if (
            !smsVerificationInfo ||
            smsVerificationInfo.validUntil.seconds <
              Firestore.Timestamp.now().seconds
          ) {
            throw Error(
              "SMS has expired or does not exist. Please send new request"
            );
          } else if (smsVerificationInfo.verificationCode != verificationCode) {
            throw Error("Incorrect verification code");
          }

          documentSnapshot.ref.update({
            smsVerificationInfo: FieldValue.delete()
          });
          documentSnapshot.ref.set(
            {
              verifiedPhoneNumber: smsVerificationInfo.phoneNumber
            },
            { merge: true }
          );
        });
      })
  }





[start:dev] Server is listening on port 4000
[start:dev] Verifying user sms verification code complete
[start:dev] (node:77536) UnhandledPromiseRejectionWarning: Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
[start:dev]     at ServerResponse.setHeader (_http_outgoing.js:535:11)
[start:dev]     at ServerResponse.header (/Users/rahmijamalpruitt/Documents/SideProjects/SonderPhoneMicroService/node_modules/express/lib/response.js:771:10)
[start:dev]     at ServerResponse.send (/Users/rahmijamalpruitt/Documents/SideProjects/SonderPhoneMicroService/node_modules/express/lib/response.js:170:12)
[start:dev]     at ServerResponse.json (/Users/rahmijamalpruitt/Documents/SideProjects/SonderPhoneMicroService/node_modules/express/lib/response.js:267:15)
[start:dev]     at ServerResponse.send (/Users/rahmijamalpruitt/Documents/SideProjects/SonderPhoneMicroService/node_modules/express/lib/response.js:158:21)
[start:dev]     at /Users/rahmijamalpruitt/Documents/SideProjects/SonderPhoneMicroService/dist/controllers/smsVerificationController.js:149:25
[start:dev]     at processTicksAndRejections (internal/process/task_queues.js:97:5)
[start:dev] (node:77536) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
[start:dev] (node:77536) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Response {
   "status": 200,
   "success": "success"
}

Answer 1

为了解决发送冲突响应的问题。我将响应处理完全排除在 verifyVerification 函数之外。我在 response.locals 对象中传递响应。

router.get(
  "/verify/:uid/:verificationCode",
  async (req: Request, res: Response, next: NextFunction) => {
    await smsVerificationController.verifyVerification(req, res, next);

    if (res.locals.error) {
      res.status(404).send({ error: res.locals.error.toString() });
    } else {
      res.status(200).json({
        success: "success"
      });
    }
  }
);

此外，我结合了该功能以获得更好的可读性。但是，此方法也适用于深度嵌套的异步函数。

public async verifyVerification(
    req: Request,
    res: Response,
    next: NextFunction
  ) {
    const { uid, verificationCode } = req.params;

    const query = firestore
      .collectionGroup("PublicUser")
      .where("uid", "==", uid)
      .limit(1)
      .get();

    await query
      .then((snapshot: any) => {
        snapshot.forEach((documentSnapshot: any) => {
          const smsVerificationInfo = documentSnapshot.get(
            "smsVerificationInfo"
          );

          if (
            !smsVerificationInfo ||
            smsVerificationInfo.validUntil.seconds <
              Firestore.Timestamp.now().seconds
          ) {
            throw Error(
              "SMS has expired or does not exist. Please send new request"
            );
          } else if (smsVerificationInfo.verificationCode != verificationCode) {
            throw Error("Incorrect verification code");
          }

          documentSnapshot.ref.update({
            smsVerificationInfo: FieldValue.delete()
          });

          documentSnapshot.ref.set(
            {
              verifiedPhoneNumber: smsVerificationInfo.phoneNumber
            },
            { merge: true }
          );
        });
      })
      .catch((error: Error) => {
        res.locals.error = error;
        next(error);
      });
  }

Answer 2

它会抛出错误，因为您发送了两次响应。 第一个在validateVerificationCode，第二个在verifyVerification。

你不应该把 async 和 promise 结合起来。

public async verifyVerification(req, res, next) {
    const {
        uid,
        verificationCode
    } = req.params;

    try {
        await this.validateVerificationCode(uid, req, res, next);
        res.status(200).json({
            success: 'success'
        });
    } catch(error => {
        res.status(404).send({ error });
    });
}


public async validateVerificationCode(uid, verificationCode, next) {
    const querySnapShot = await firestore.collectionGroup("PublicUser").where("uid", "==", uid).limit(1).get();

    querySnapShot.forEach(documentSnapshot => {
        const smsVerificationInfo = documentSnapshot.get('smsVerificationInfo');
        const invalidTime = smsVerificationInfo.validUntil.seconds < Firestore.Timestamp.now().seconds;

        if(!smsVerificationInfo || invalidTime) {
            throw new Error('SMS has expired or does not exists. Please send new request');
        }

        if(smsVerificationInfo.verificationCode !== verificationCode) {
            throw new Error('Incorrect verification code');
        }


        documentSnapshot.ref.update({
            smsVerificationInfo: FieldValue.delete()
        });

        documentSnapshot.ref.set({
            verifiedPhoneNumber: smsVerificationInfo.phoneNumber
        }, { 
            merge: true 
        });
    });
}