hwjs

Highway.js

A flexible pub/sub event emitter for web-worker cross-communication with fallback support.

Usage

Include Highway.js on both client side and worker side.

Client:

<script src="Highway.js"></script>

Worker:

importScripts('Highway.js')

Initialize:

// Client side
var Host = self.Worker ? new self.Worker('worker.bundle.js') : self
self.HW = self.HW || new self.Highway(Host)
// Worker side
self.HW = self.HW || new self.Highway()

Note that you cannot use importScripts in case you want proper fallback when there is no web-worker support. In that case you need to include a bundle in new Worker('worker.bundle.js') and the bundle should also include Highway. This way you can include your worker bundle on the client side after no worker support is detected.

// On client side
if (!self.Worker) {
    var script = document.createElement('script')
    script.setAttribute('src', 'worker.bundle.js')
    document.body.appendChild(script)
}

In most cases you want to initialize client side stuff after the worker is loaded. Use your own event for this. For example you need your data model from the backend before rendering the site.

// Client side
self.HW.one('ready', function(){
    InitSomeGUIFramework()
})
// Worker side
InitSomeDataModelStuff()
InitSomeWebSocketConnection()
self.HW.pub('ready')

API

sub

Subscribe to an event.

self.HW.sub('MyOwnEvent', function(){
    // Do something when event occurs
    // See pub, this will run 3 times
})
self.HW.sub('MyOwnEvent->DidSomething', function(){
    // Do something when event occurs
    // See pub, this will run once
})

pub

Publish an event.

self.HW.pub('MyOwnEvent', customData)
self.HW.pub('MyOwnEvent->DidSomething', customData)
self.HW.pub('MyOwnEvent->IHaveState', customData, 'passed')

one

Subscribe to an event, unsubscribe once it is called.

self.HW.one('MyOwnEventOnce', function(){
    // I'll just run once and automatically unsubscribe then
})

exe

Execute a function on the other side. Your function will be executed within self context.

self.HW.exe(function(){
    // Do some code
})

off

Unsubscribe from an event.

// Unsubscribe from ALL events associated with MyOwnEvent
self.HW.off('MyOwnEvent')
// Unsubscribe only a specific function
self.HW.off('MyOwnEvent', handlerFunction)
// Unsubscribe from ALL events associated with MyOwnEvent and event the deep ones. eg: MyOwnEvent->DeepEvent too
self.HW.off('MyOwnEvent', true)

destroy

Destroy the Highway instance.

self.HW.destroy()

Credits

Victor Vincent DoclerLabs