events

Event listeners attach handlers to DOM elements using addEventListener(). I specify event type like click, input, submit with handler function. The event object contains information about the triggered event. Using event.preventDefault() stops default

LISTEN/NOTIFY provides real-time pub-sub messaging. Publishers send notifications via NOTIFY. Subscribers receive notifications via LISTEN. I use it for cache invalidation, real-time updates, inter-process communication. Payloads up to 8000 bytes carr

The moment you split ‘write to DB’ and ‘publish to a queue’ into two independent operations, you create a place to lose data. Publish first and a DB failure means consumers act on something that never happened. Write first and a publish failure means

Observers consolidate model event listeners in dedicated classes, preventing bloated models. Each observer method corresponds to an Eloquent event—creating, created, updating, updated, deleting, deleted. I register observers in boot() methods of servi

Signals allow different parts of the application to respond to model events without tight coupling. I use post_save for actions after an object is created or updated, like sending notifications or updating related records. The @receiver decorator is c

Not every integration payload maps cleanly to a static struct. When I need to accept “mostly known” JSON but preserve unknown fields for auditing or forward compatibility, I use json.RawMessage. That allows me to decode the envelope (event name, versi

Spring's event mechanism enables loose coupling between components. ApplicationEventPublisher publishes events. @EventListener handles events asynchronously or synchronously. Events extend ApplicationEvent or are POJOs. @TransactionalEventListener pub

Events and listeners decouple application logic, making code modular and testable. When significant actions occur—user registered, order placed—I fire events. Multiple listeners can respond to one event without the event knowing about them. Events are