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在异步等待中尝试catch的问题

[英]Issue with try catch in async await

I am struggling with async await try catch block for a couple of days. 我正在努力与异步等待尝试catch块几天。

async function executeJob(job) {

  // necessary variable declaration code here

  try {
    do {
      let procedureRequests = await ProcedureRequestModel.find(filter, options);

      // doing process here...

    } while (fetchedCount < totalCount);

    providerNPIIds = [...providerNPIIds];

    // Fetch provider details
    let providerDetails = await esHelper.getProvidersById(providerNPIIds, true);

    try {

      let updateProviderCount = await UserProvider.updateAll(
          {
            userId: userId
          },
          {
            providers: providerNPIIds,
            countByType: providerCountType
          });

      if(updateProviderCount) {
        try {
          let destroyJobId = await  app.models.Job.destroyById(job.idd);
        } catch (e) {
          var err = new QueueError();
          console.log(err instanceof QueueError);
          throw new QueueError();
        }

      }
    } catch (e) {
      logger.error('Failed to update UserProviders  & Count: %O', err);
      throw e;
    }

    executeNextJob();
  } catch (e) {
    if(e instanceof QueueError) {
      console.log('Exiting from process');
      process.exit(1);
    } else {
      console.log('Working Code');
      buryFailedJobAndExecuteNext(job);
    }

  }
}

Is my try catch in this async function proper? 我尝试捕获这个异步功能吗?

This is how I created Custom Error Class and exported globally. 这就是我创建自定义错误类并全局导出的方法。

// error.js file

class QueueError extends Error {

}

global.QueueError = QueueError;

The requirement: 要求:

Intentionally changed job.id to job.idd in 故意改变了job.id到job.idd in

let destroyJobId = await  app.models.Job.destroyById(job.idd); 

so that I can catch error. 这样我就能发现错误。 If there is error then throw newly created custom Error class. 如果有错误,则抛出新创建的自定义Error类。 But throwing QueueError will cause logging 但抛出QueueError会导致日志记录

logger.error('Failed to update UserProviders  & Count: %O', err); 

too , even though no need to catch error there, since try block is working If I throw QueueError I only wants to catch error in last catch block only. 即使不需要在那里捕获错误,因为try块正在工作如果我抛出QueueError我只想在最后一个catch块中捕获错误。

Below is the callback version, I am converting it into async await. 下面是回调版本,我将其转换为异步等待。

 Updating providersNPIId & category count
     UserProvider.updateAll({userId: userId},
       {
         providers: providerNPIIds,
         countByType: providerCountType,
       }, function(err, data) {
         if (err) {
           logger.error('Failed to update UserProviders  & Count: %O', err);
           // throw new QueueError();
         }
         // Remove countProvider Job
         app.models.Job.destroyById(job.id, function(err) {
           if (err) {
             logger.error('Failed to remove countProvider job: %O', err);

           }
         });
       });

You can refactor your code in smaller functions that return a promise for which you can locally wrap try-catch and handle it. 您可以在较小的函数中重构代码,这些函数返回一个promise,您可以在本地包装try-catch并处理它。

async function executeJob(job) {

  // necessary variable declaration code here
  try {

    await doProcedure();

    providerNPIIds = [...providerNPIIds];

    // Fetch provider details
    let providerDetails = await esHelper.getProvidersById(providerNPIIds, true);
    const updateProviderCount = await getProviderCount(userId, providerNPIIds, providerCountType);

    if(updateProviderCount) {
        await destroyJobById(job.idd);
    }

    executeNextJob();
  } catch (e) {
    if(e instanceof QueueError) {
      console.log('Exiting from process');
      process.exit(1);
    } else {
      console.log('Working Code');
      buryFailedJobAndExecuteNext(job);
    }
  }
}

async function doProcedure() {
    try {
        do {
          let procedureRequests = await ProcedureRequestModel.find(filter, options);

          // doing process here...

        } while (fetchedCount < totalCount);
    } catch (err) {
        throw err;
    }
}

async function getProviderCount(userId, providerNPIIds, providerCountType) {
    try {
        let updateProviderCount = await UserProvider.updateAll({ userId: userId }, { providers: providerNPIIds, countByType: providerCountType });
        return updateProviderCount;
    } catch (err) {
      logger.error('Failed to update UserProviders  & Count: %O', err);
      throw e;
    }
}

async function destroyJobById(Id) {
    try {
          let destroyJobId = await app.models.Job.destroyById(Id);
    } catch (err) {
          throw err;
    }
}

This is basically the same what You have: 这与你的基本相同:

1 function myFunctionPromise() {                                                                                     
2   return new Promise((response, reject) => {                                                                       
3       setTimeout(() => reject("Reject Err"), 3000);                                                                
4   });                                                                                                              
5 } 

7 async function myFunction() {                                                                                      
8      try {                                                                                                         
9        try {                                                                                                       
10          await myFunctionPromise();                                                                                
11        } catch(e) {                                                                                                
12          console.log("Second Err");                                                                                
13          throw e;                                                                                                  
14        }
15 
16      } catch (e) {                                                                                                 
17        throw e;
18      }
19 
20      console.log("test");
21 }
22 
23 
24 myFunction()

The only difference I see it's the Reject of the promise line #3. 我看到的唯一区别是承诺线#3的拒绝。 So I'm wondering if: 所以我想知道是否:

let destroyJobId = await app.models.Job.destroyById(job.idd); let destroyJobId = await app.models.Job.destroyById(job.idd);

It's rejecting properly the promise. 它正确地拒绝承诺。

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