The Observer Pattern: Synchronous and Asynchronous Events
Explore the Observer pattern in Node.js by understanding the differences between synchronous and asynchronous event emission. Learn how to register listeners correctly to avoid missing events and prevent issues like mixing emissions, ensuring robust asynchronous control flow using EventEmitter.
We'll cover the following...
We'll cover the following...
Synchronous and asynchronous events
Similar to callbacks, events can also be emitted synchronously or asynchronously with respect to the moment the tasks that produce them are triggered. It’s crucial that we never mix the two approaches in the same EventEmitter, but even more importantly, we should never emit the same event type using a mix of synchronous and asynchronous code, to avoid producing the same problems described in the “Unleashing Zalgo” section. The ...