Multithreading in Node.js

In Node.js, the term multithreading doesn’t apply because Node.js is designed to be run in a single-threaded event loop. However, Node.js is built on top of the JavaScript language, which is single-threaded by default.

However, Node.js provides some ways to perform concurrent programming tasks. One way to do this is by using the child_process module, which allows you to spawn new processes that can run concurrently with the main Node.js process.

Another way to perform concurrent tasks in Node.js is by using the async/await syntax, which allows you to write asynchronous code that looks like it is synchronous. This can make it easier to write code that performs multiple tasks concurrently without having to explicitly spawn new processes or use callbacks.

For example, the following code uses async/await to perform two tasks concurrently.

async function runTasks() {
  const task1 = doTask1();
  const task2 = doTask2();

  await Promise.all([task1, task2]);
}

In this example, doTask1 and doTask2 are asynchronous functions that return Promises. The await operator is used to wait for both Promises to resolve before continuing.

This allows the two tasks to be performed concurrently rather than sequentially. It’s worth noting that the async/await syntax is built on top of the JavaScript Promise type, which allows you to write asynchronous code in a way that is more like traditional synchronous code.

The child_process module in Node.js provides an easy way to spawn new processes. It allows you to run external programs, such as Bash scripts or other executables, from within a Node.js program.

Implement Multithreading in Node.js

Here’s an example of using the child_process module to run a Bash script.

In this example, the exec function is used to execute a Bash script called bash_script.sh. The function takes a callback that is called when the process finishes.

The callback receives three arguments: error, stdout, and stderr. These arguments contain the error that occurred, the process’s standard output, and the process’s standard error, respectively.

The child_process module provides several other functions for spawning processes, such as spawn, fork, and execFile. Each of these functions has its own set of options and behavior, so you can choose the one that best fits your needs.

const {exec} = require('child_process');

exec('bash_script.sh', (error, stdout, stderr) => {
  if (error) {
    console.error(`exec error: ${error}`);
    return;
  }
  console.log(`Script run successfully`);
});

Output:

stdout:
stderr:
Script run successfully