Jumping over loop iteration following a JavaScript catch block

Question

Jumping over loop iteration following a JavaScript catch block

Currently, I am developing an API that requires making repeated calls to another API (specifically, Quickbooks Online) within a loop. These calls are encapsulated in promises that either resolve or reject based on the response from Quickbooks. Everything functions as expected, but I am looking for a way to allow the loop to continue execution after handling errors. At present, when an error is caught, it gets logged into the database, but the loop halts and no further calls are executed. I have attempted using "return" and "continue" inside the catch block without success.

Below is an example of the code:

// This is a section of a larger loop. Needs to be asynchronous
await paymentInfo.forEach(async ln => {

        var payRef = ln.payment_ref
        var vendor = ln.vendor_id

        var finalPayment = await service.createPayment(args)
          .then(console.log("Payment created"))
          .catch((err) => { 

            // Log the error to the database
            service.dbUpdate(err)
            .then(console.log("Error Logged to DB"))
            .catch(() => {})

            // How do we proceed from here?
       })
      // Update the database with payment ID here
})

In essence, I simply want to be able to continue to the next iteration of the loop after catching an error. As far as I can see, there isn't a straightforward way to achieve this. Any suggestions would be greatly appreciated.

javascript foreach promise async-await

Answer 1

Answer №1

If you are already using async/await, there is no need for .then method. Simply utilize await and catch errors with a traditional try/catch block. The continue statement will work naturally when placed inside a for loop. However, it appears that you need to handle the loop iterations in parallel, so each iteration should be contained within a function invocation where you can return.

Another issue present is the lack of error handling in your async function due to not being awaited. Instead of awaiting forEach, which does not return anything, one solution is to map your array into an array of promises (the result of executing anonymous async functions) and then await all those promises simultaneously using Promise.all.

await Promise.all(paymentInfo.map(ln => (async () => {
        var payRef = ln.payment_ref
        var vendor = ln.vendor_id

        try {
            var finalPayment = await service.createPayment(args)
            console.log("Payment created")
        } catch (err) {
            // Log error to DB
            try {
                await service.dbUpdate(err)
                console.log("Error Logged to DB"))
            } catch (e) {}

           return
        }

       // Database update here with payment ID
})())

It may be unnecessary to have a continue statement if the only purpose was to react to the possibility of a payment not being created. In such case, you would simply use the payment value unconditionally, as any error thrown would skip the rest of the try block anyway!

await Promise.all(paymentInfo.map((async ln => {
        var payRef = ln.payment_ref
        var vendor = ln.vendor_id

        try {
            var finalPayment = await service.createPayment(args)
            console.log("Payment created")

            // Database update here with payment ID
        } catch (err) {
            // Log error to DB
            try {
                await service.dbUpdate(err)
                console.log("Error Logged to DB"))
            } catch (e) {}
        }
})())

Answer 2

If you are already using async/await, there is no need for .then method. Simply utilize await and catch errors with a traditional try/catch block. The continue statement will work naturally when placed inside a for loop. However, it appears that you need to handle the loop iterations in parallel, so each iteration should be contained within a function invocation where you can return.

Another issue present is the lack of error handling in your async function due to not being awaited. Instead of awaiting forEach, which does not return anything, one solution is to map your array into an array of promises (the result of executing anonymous async functions) and then await all those promises simultaneously using Promise.all.

await Promise.all(paymentInfo.map(ln => (async () => {
        var payRef = ln.payment_ref
        var vendor = ln.vendor_id

        try {
            var finalPayment = await service.createPayment(args)
            console.log("Payment created")
        } catch (err) {
            // Log error to DB
            try {
                await service.dbUpdate(err)
                console.log("Error Logged to DB"))
            } catch (e) {}

           return
        }

       // Database update here with payment ID
})())

It may be unnecessary to have a continue statement if the only purpose was to react to the possibility of a payment not being created. In such case, you would simply use the payment value unconditionally, as any error thrown would skip the rest of the try block anyway!

await Promise.all(paymentInfo.map((async ln => {
        var payRef = ln.payment_ref
        var vendor = ln.vendor_id

        try {
            var finalPayment = await service.createPayment(args)
            console.log("Payment created")

            // Database update here with payment ID
        } catch (err) {
            // Log error to DB
            try {
                await service.dbUpdate(err)
                console.log("Error Logged to DB"))
            } catch (e) {}
        }
})())

Jumping over loop iteration following a JavaScript catch block

Answer №1

Similar questions

Resposiveness of force-directed graph is lost

Obtaining varied outcomes while printing filtered information

An error has occurred with TokBox: OT.Session is unable to connect because the session has already been declared as

Is Node.js functioning properly, but how can I incorporate it into a web browser?

Deconstructing arrays in the req.body object in a Node.js Express application

Tips for developing an asynchronous function for data requests in reactjs

Encountering an issue when running the command "ng new my-app" after updating the @angular/cli package

Question about using React, NPM, Vite, Babel, and Node.js together

What triggers the execution of the catch method while chaining HTTP promises?

Unable to display an image element in fullscreen within a modal that is already fullscreen

Trouble updating outside controller data while using AngularJS directive inside ng-repeat loop

The JQuery parseFloat() function seems to be consistently returning "NAN" whenever it is used with the .text property

Adjusting the size and location of the current browser window using jQuery

Problems with Key Presses in Form Verification

"Learn how to use jQuery to retrieve a specific row from an HTML table based on equality with a certain

Tips for inserting HTML into elements using Angular

Ensuring input validity and blocking changes if not compliant with AngularJS patterns

Tips for transferring data from Express to .ejs file during redirection in Node.js

Executing HTTP Requests for Elements in an Array using JavaScript

AngularJS - Sending event to a specific controller