CAROLINA DOCS

---

Events

The "events" app fires events by passing them to listener functions.

The Events Service

When the "events" service is loaded, it will read events.js from the app directories of every installed app, and track which listener functions should react to which named events.

To fire an event (meaning have an object passed to all listeners set up to react to that event name), use the fire method:

App.$events.fire('my_custom_event', { number: 4 });

The "events" service would then asynchronously pass the given object to all listener functions confiugred to listen for "my_custom_event".

Events Configuration

The default "events" app configuration looks like this:

module.exports = {
  fireEvents: true
};

If the fireEvents property is false, calls to $events.fire will be ignored.

You can copy the configuration file to config/events.js using the following command:

node . publish --config events

Writing Listeners

A listener is a function that takes a single argument (which will be the data passed when the event is fired).

function myListener(eventData) {
  // do something with my event
}

The function can by async, but it will not be awaited.

To register a listener function from one of your apps, export a map of event names to arrays of listener functions from event.js in your app directory.

Example:

// apps/my_custom_app/events.js

module.exports = {
  some_event_name: [
    (data) => { console.log(data); }
  ]
};

---

CAROLINA DOCS