simple-watcher-js v0.0.23

simple-watcher-js

A tool to watch javascript objects.

Install

npm install simple-watcher-js --save 

Example

// Import watcherJS ES6 module
import watcherJS from 'simple-watcher-js'

// Or import ES5 build
<script src="./node_modules/simple-watcher-js/build/watcherjs.min.js"></script>

// My object
const user = {
  username: 'John Doe'
}

// Listen updates on "username" property
const userWatcher = watcherJS.set(user, 'username', (event, property, value) => {
  console.log('Your username has been updated!')
})

// Or listen all events for each properties 
const userWatcher = watcherJS.watch(user, (event, property, value) => {
  if (event === 'set' && property === 'username') {
    console.log('Your username has been updated!')
  }
})

// Updates to trigger callback
userWatcher.username = 'John Bilout'

Usage

The watching functions take at least two parameters, target and callback, it can also has property parameter in second position. If property is defined as null then it's as not defined.

// Watch full object.
watcherJS.watch(target, callback)

// Watch only defined property
watcherJS.watch(target, property, callback)

• target: Object - Object we need to watch.
• property: String - Property to trigger events.
• callback: Function - Callback event.

From the callback parameters you can retreive

• event - Current affected event.
• property - Current affected property.
• value - Current affected value.

API

• watcherJS.set(target, ...arguments) - Watch updates events.
• watcherJS.get(target, ...arguments) - Watch readings events.
• watcherJS.has(target, ...arguments) - Watch "in" operator usage.
• watcherJS.watch(target, ...arguments) - Watch all events.