How to use Async/Await To make a HTTP request?

Async/await is a language feature in JavaScript that allows you to write asynchronous code in a synchronous-looking style.

Asynchronous code is code that runs in a non-blocking manner, meaning that it does not prevent other code from running while it is executing.

This is important in JavaScript because the language is single-threaded, meaning that only one piece of code can run at a time.

Async/await makes it easier to write and manage asynchronous code by allowing you to use the await keyword to wait for a promise to resolve before moving on to the next line of code.

Here is an example of how you can use async/await to make an asynchronous HTTP request:

async function makeRequest() {
  const response = await fetch('https://www.example.com/api/endpoint');
  const data = await response.json();
  console.log(data);
}

In this example, the makeRequest function uses the fetch function to make an HTTP request to a specified URL. The await keyword is used to wait for the promise returned by the fetch function to resolve before calling the json method on the response object.

This allows the code to run in a synchronous-looking manner, without blocking other code from running while the request is being made and the response is being parsed.

Async/await can make it easier to write and manage asynchronous code in JavaScript, and can help improve the performance and reliability of your code.

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It is a useful tool to have in your programming toolkit. Async/await is built on top of promises, and it uses the async and await keywords to make asynchronous code easier to understand and write.

The async keyword is used to define an asynchronous function, and the await keyword is used to wait for a promise to be resolved before continuing with the code.

Here are some best practices for using async/await in JavaScript

1. Use the async keyword to mark functions that contain one or more await expressions. This ensures that the function always returns a promise, which allows you to use async/await consistently throughout your code.
2. Use the await keyword to wait for a promise to be resolved before continuing with the code. This makes it easy to read and understand the flow of your asynchronous code.
3. Handle errors gracefully by using a try/catch block around your await expressions. This allows you to catch any errors that might occur and handle them appropriately.
4. Use async/await for asynchronous code that is independent of other asynchronous operations. If you need to perform multiple asynchronous operations in parallel, consider using Promise.all() instead of await.
5. Avoid using async/await for code that needs to run immediately, without waiting for a promise to be resolved. In these cases, it is better to use a regular then/catch block or a Promise.race() instead.

By following these best practices, you can write asynchronous code that is easy to read, understand, and maintain.

When not to use Async/Await

You should not use async/await for code that needs to run immediately, without waiting for a promise to be resolved.

For example, if you have a piece of code that needs to run as soon as possible, such as updating the UI or logging a message to the console, using await to wait for a promise to be resolved will introduce unnecessary delays and make your code less efficient.

In these cases, it is better to use a regular then/catch block or a Promise.race() to handle the asynchronous operation. This allows you to run your code immediately and handle the asynchronous operation separately, without introducing any delays.

Here is an example of how you might use a regular then/catch block instead of async/await to handle an asynchronous operation:

function getData() {
  // do not use await, just return the promise
  return fetch('https://www.example.com/data.json')
    .then(response => response.json())
    .catch(error => console.log(error));
}

// call the getData function without using await
getData().then(data => console.log(data));

In this example, the getData function does not use the async keyword or the await keyword. Instead, it returns the fetch promise directly, and the caller can use a regular then/catch block to handle the promise. This allows the code to run immediately without waiting for the promise to be resolved.