npm:x-dispatcher

README

Lightweight Event Dispatcher (umd support), allowing you dispatch anywhere in the code, very handy in callback hell situations, deep promises, or any other complicated computations. Integrated with callback memory (so you dont have to subscribe first to get your data.)

Install:

/$ npm i x-dispatcher

Why use it ?

Avoid ugly callback > callback > callback hell!
Avoid messy Promises
Prefer clean, readable code hierarchy
Easy to implement
No dependencies
UMD/esm support so you can use same declaration in most environments: (AMD, Node, or browser)

Example

    // import { xdispatcher } from 'x-dispatcher/esm' when using esm or ts
    const { xdispatcher } = require('x-dispatcher') // /node or /umd can also be used 
    const uid = `dispatch_job_1` // optional
    const DEBUG = true // optional
  
    const ds = xdispatcher(uid, DEBUG)

    // thanks to callback memory `next` can be called before subscribe!
    ds.next({ type: 'profile', data: { address: 'xox', email: 'johndoe@email.xo', name: 'John Doe', company: 'Anonymous' } })

    .subscribe(function(data, uid, index){
        console.log('on subscribe', data, this.uid, index)
        // this.unsubscribe() 
    })
    .onComplete(uid=>{
        console.log(`unsubscribed from ${uid}`)
    })

    setTimeout(() => {
        ds.next({ data: { company: "Secret delayed" } })
          .next({ data: { company: "another Secret delayed" } }) // and so on
          .unsubscribe()
          .next({ data: { company: "never received" } }) // never called

          console.log(ds.isActive()) //:false
    }, 2000)

More Examples

Checkout ./examples.js

Version support

es5/es6 support for universal module, can use for: AMD, Node, or browser

const { xdispatcher } = require('x-dispatcher') // defaults to node
const { xdispatcher } = require('x-dispatcher/umd') 
const { xdispatcher } = require('x-dispatcher/node') // umd/es6 
import { xdispatcher } from 'x-dispatcher/esm' 

<script src="..path/x-dispatcher/umd">
   const xd = window.xdispatcher() // initialize new
</script>

Methods

METHODS	RETURN	DESCRIPTION
subscribe( (data,uid,index)=> )	`self`	start listening for events, before or after `next()`. `uid`=> default of provided id for this dispatcher. `index`=> counts callback events.
onComplete( (uid)=> )	`self`	when subscribe event is deleted, callback is initiated
next( data )/emit( data )	`self`	send data to `subscribe` callback. Can be declared before `subscribe` was initialized, there are no timers, so do not worry about memory leaks!
del()/delete()/unsubscribe()	`self`	remove dispatcher from stack
isActive()	`boolean`	tells you if dispatcher is still active

Stack

es5/es6, Javascript, lint, callback, chaining support, umd, commonjs, node.js

Contact

Have questions, or would like to submit feedback, contact eaglex

x-dispatcherdeprecated

Usage no npm install needed!