How to Return Response From an Asynchronous Call in JavaScript

In this blog, we will be writing script for this app using async/await and promise .then syntax . We will also write scripts for other apps as well. Keep on reading as this article is written in depth. We will first understand what is asynchronous call and callback hell. Then we will discuss different approaches to write asynchronous code.

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Disclaimer: This application is built for educational purposes. Jokes are not filtered, and we are not responsible if any joke offends anyone. The random joke is fetched from the third party API.

Asynchronous call in programming is a way of doing tasks without waiting for them to finish before moving on to the next task. Instead of waiting, the program can continue doing other things and get back to the task when it’s done.

For example, let’s say you want to fetch some data from a remote server. In a synchronous scenario, the program would make the request and wait until it receives the data before doing anything else. But with an asynchronous call, the program can make the request and move on to other tasks without waiting. Once the data is ready, the program will be notified and can handle the data.

Asynchronous calls are often used for tasks like making network requests, reading/writing files, working with databases, or doing computations that take a long time. By using asynchronous calls, programs can be more efficient, responsive, and able to handle multiple tasks at the same time.

In JavaScript, asynchronous calls are commonly managed using techniques like callbacks, promises, or the newer async/await syntax. These techniques provide ways to handle the asynchronous response and ensure that the program flows smoothly even when dealing with time-consuming tasks.

Callback Hell :

Now, let’s talk about “callback hell.” It refers to a situation where you have multiple nested callbacks in your code, making it difficult to read and understand. Here’s an example:

asyncOperation1(arg1, (error1, result1) => {
  if (error1) {
    console.error(error1);
  } else {
    asyncOperation2(arg2, (error2, result2) => {
      if (error2) {
        console.error(error2);
      } else {
        asyncOperation3(arg3, (error3, result3) => {
          if (error3) {
            console.error(error3);
          } else {
            // Continue with more nested callbacks...
          }
        });
      }
    });
  }
});

In this example, there are three asynchronous operations (asyncOperation1, asyncOperation2, and asyncOperation3) that depend on each other. As a result, the callbacks are nested inside each other, creating a deep indentation and making the code hard to follow.

Each callback checks for errors and handles them if they occur. If there are no errors, it moves on to the next asynchronous operation, leading to more levels of nesting. This nesting can quickly become overwhelming and make the code difficult to manage and maintain.

Callback hell can make code harder to debug, test, and understand, which leads to poor code quality. It lacks the readability and clarity provided by Promise-based or async/await syntax, which offer more structured and sequential ways to handle asynchronous operations.

To mitigate callback hell, you can use Promises or async/await syntax, as will be shown in the upcoming examples. These approaches provide cleaner and more organized ways to handle asynchronous code, making it easier to read, write, and maintain.