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How Run Async Await In Parallel In Javascript

Async/await in JavaScript has revolutionized the way developers handle asynchronous operations, making code more readable and maintainable. However, there are situations where you might want to run multiple asynchronous tasks concurrently using async/await. In this article, we will dive into the nitty-gritty of running async/await in parallel in JavaScript.

To run async/await in parallel, we can leverage JavaScript's `Promise.all()` method along with `async` functions. First things first, ensure that the functions you want to run in parallel are marked as `async`. This means they will return Promises, allowing us to use async/await syntax.

Let's say we have two async functions, `getData1()` and `getData2()`, that make asynchronous calls to fetch some data. To run them in parallel, you can use the following approach:

Javascript

const getData1 = async () => {
  // Async operation
};

const getData2 = async () => {
  // Async operation
};

const fetchData = async () => {
  const [result1, result2] = await Promise.all([getData1(), getData2()]);

  console.log(result1, result2);
};

fetchData();

In the above code snippet, we define two async functions, `getData1()` and `getData2()`, which simulate asynchronous operations. The `fetchData()` function leverages `Promise.all()` to run both async functions concurrently. By awaiting the `Promise.all()` call, we wait for all promises to resolve before proceeding, and then we can access the results.

It's important to note that `Promise.all()` takes an array of Promises and returns a single Promise that resolves when all input Promises are resolved.

If you need to run a dynamic number of async functions in parallel, you can dynamically create an array of Promises and pass it to `Promise.all()`. Here's an example:

Javascript

const fetchData = async () => {
  const asyncTasks = [getData1(), getData2(), getData3()];
  const results = await Promise.all(asyncTasks);

  console.log(results);
};

fetchData();

In this example, we have an array `asyncTasks` containing references to async functions `getData1()`, `getData2()`, and `getData3()`. By passing this array to `Promise.all()`, we run all the async tasks concurrently and wait for their completion.

Running async/await functions in parallel can greatly improve the performance of your JavaScript code, especially when dealing with independent asynchronous tasks. Just remember to handle errors appropriately, either within the async functions themselves or by wrapping the `Promise.all()` call with a try-catch block.

By mastering the art of running async/await in parallel in JavaScript, you can unleash the full potential of this powerful language feature and build more efficient and responsive applications. Happy coding!