preload.io-json v1.1.0

preload.io-json

Preload.io loader for json

Installation

npm i preload.io-json

Polyfills

Image requires a few polyfills to work everywhere, to give some flexibility they are not included by default.

npm i -S whatwg-fetch regenerator

import 'regenerator/runtime'
import 'whatwg-fetch'

Regenerator is currently a requirement for the async stuff, but a version is included with babel-polyfill so if you’re using that then you’re good to go. Use whichever version of fetch you like, if necessary.

There will be a fairly obvious console error logged if these are omitted.

Getting Started

Install preload.io and register the json loader with it

import Preloader from 'preload.io'
import { EVENTS } from 'preload.io'
import JSONLoader from 'preload.io-json'

let preloader = new Preloader()
preloader.register( new JSONLoader() )

Then just load the resource and listen for the response, which will be parsed already

let id = preloader.load( 'https://api.github.com/users/mattstyles' )

preloader.on( EVENTS.LOAD, event => {
  if ( event.id === id ) {
    console.log( event.res ) // { login: 'mattstyles' ... }
  }
})

Passing options to fetch

JSONLoader uses fetch to preload the resource, options you supply will be passed to fetch, in this order of precedence:

preloader.load({
  resource: 'stuff.json',
  options: {
    mode: 'no-cors'
  }
})

const jsonLoader = new JSONLoader({
  mode: 'no-cors'
})

const preloader = new Preloader({
  mode: 'no-cors'
})