How to run N async tasks in series using JavaScript

How to run N async task in series using JavaScript

To run N asynchronous tasks in series using JavaScript, we can make use of `async/await` and a loop. Here’s an example program that demonstrates how to achieve this:

async function runTasksInSeries(tasks) {
  for (let task of tasks) {
    await task();
  }
}

// Example asynchronous tasks
function asyncTask1() {
  return new Promise(resolve => {
    setTimeout(() => {
      console.log('Async task 1 completed');
      resolve();
    }, 1000);
  });
}

function asyncTask2() {
  return new Promise(resolve => {
    setTimeout(() => {
      console.log('Async task 2 completed');
      resolve();
    }, 2000);
  });
}


function asyncTask3() {
  return new Promise(resolve => {
    setTimeout(() => {
      console.log('Async task 3 completed');
      resolve();
    }, 1500);
  });
}

// Define your tasks in an array
const tasks = [asyncTask1, asyncTask2, asyncTask3];

// Run the tasks in series
runTasksInSeries(tasks)
  .then(() => {
    console.log('All tasks completed');
  })
  .catch(error => {
    console.error('Error occurred:', error);
  });

/* Output:-
"Async task 1 completed"
"Async task 2 completed"
"Async task 3 completed"
"All tasks completed"
*/

In this example, we have three asynchronous tasks (`asyncTask1`, `asyncTask2`, `asyncTask3`) that simulate some asynchronous operations using `setTimeout`. The `runTasksInSeries` function takes an array of tasks as input and runs them in series using a `for` loop and `await`. Each task is awaited, meaning the next task won't start until the previous one has completed.

We can modify the example by adding or removing tasks from the `tasks` array to run a different number of asynchronous tasks in series.

Hope this helps. Have a nice day ahead 😁