A universal, human-centric, replayable javascript event emitter.
A universal, human-centric, replayable event emitter.
The world just like software is full of events. Sometimes these events occur while we are busy doing other things. Wouldn't it be nice to have a way to replay all events? Noel is the way.
By being able to replay events we can design reactive systems without having to worry about timing.
For example, code like
// Check if there is a user in case we missed the userChanged event
const user = sessionService.getUser();
if(user) updateAvatarPhoto(user)
// Listen for further changes
sessionService.listenUserChanged(updateAvatarPhoto);
can become
sessionService.listenUserChanged(doSomethingWithUser).replay();
Meaning that if the userChanged
event was already fired, it will be replayed with the last arguments and if it gets fired again, we'll be listening.
npm install noel
const Noel = require('Noel');
const noel = new Noel();
// Listen for an event
noel.on('friday', partyAllNightLong);
// Emit an event
noel.emit('friday', arg1, arg2 ....);
// Replay an event once
noel.on(eventName, eventListener).replay();
// Replay an event x amount of times
noel.on(eventName, eventListener).replay(x);
// When creating the noel instance
const noel = new Noel({
replay: false
});
// At runtime
noel.disableReplay(anotherBufferSize);
Please do note that replay is enabled by default, so this should only be necessary if it was disabled at runtime.
// At runtime
noel.enableReplay(anotherBufferSize);
noel.removeListener(eventName, eventListener);
or if you save a reference to the eventManager
const eventManager = noel.on('myEvent', eventListener);
// ...
eventManager.remove();
noel.removeAllListeners(eventName, eventListener);
If you would like to clear all saved event emissions for replay
noel.clearReplayBufferForEvent(eventName);
If you would like to clear all saved events emissions for replay
noel.clearEventsReplayBuffers();
Or in human words, changing the amount of event emissions that are saved for replays.
Default is 1.
// When creating the noel instance
const noel = new Noel({
replayBufferSize: aNewBufferSize
});
// ...
// At runtime
noel.setReplayBufferSize(anotherBufferSize);
When an event is emitted, no listeners have been set AND the replay was disabled so there is no way of doing anything with the emission, a warning will be logged into the console if available. To disable this behaviour:
// When creating the noel instance
const noel = new Noel({
noEventListenersWarning: false
});
// ...
// At runtime
noel.disableNoEventListenersWarning();
Please do note that the no event listeners warning is enabled by default, so this should only be necessary if it was disabled at runtime.
noel.enableNoEventListenersWarning();
git clone [email protected]:lifenautjoe/noel.git
npm t
: Run test suitenpm start
: Runs npm run build
in watch modenpm run test:watch
: Run test suite in interactive watch mode
npm run test:prod
: Run linting and generate coveragenpm run build
: Generate bundles and typings, create docsnpm run lint
: Lints codenpm run commit
: Commit using conventional commit style (husky will tell you to use it if you haven't :wink:)Author Joel Hernandez