Learn Node.js: The Complete Course for Beginners/

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Process

Process

Understand how the process object works in Node.js.

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The process object

The process object is a global that allows us to control the current process. It also has methods that can provide useful information about the process. Being an instance of the EventEmitter class, it has a few important events that we should know about. Let’s take a look at them.

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console.log('This is the first message');
process.on('beforeExit', (code) => {
  console.log('Process beforeExit event with code:', code);
});
process.on('exit', (code) => {
  setTimeout(() => { console.log('This will not work.') }, 0);
  console.log('Process exit event with code:', code);
});
console.log('This is the second message');
// process.exit()

exit and beforeExit

These two events can be very useful at times. Consider the scenario:

  • You wish to save your program progress to the cloud once it is done processing. The beforeExit event is perfect for this job. It is firedemitted when the event loop is empty, which means that Node.js has done all its work and is about to exit. You can register the beforeExit event to make a network call to your cloud drive and upload your data.
  • Once your data has been
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