@digitalkaoz/preload-polyfill

polyfilling [link rel=preload]

Stats

StarsIssuesVersionUpdatedCreatedSize
@digitalkaoz/preload-polyfill
1.22.53 years ago4 years agoMinified + gzip package size for @digitalkaoz/preload-polyfill in KB

Readme

Preload Polyfill

it just works...

What & Why

preload seems the best async loading mechanism today...

https://caniuse.com/#search=preload

some good reads:

Install with npm

npm install @digitalkaoz/preload-polyfill

Usage

This Polyfill supports the following types:

  • js
  • css
  • font
  • image
  • audio (not well tested)
  • document (not well tested)
  • embed (not well tested)
  • fetch (not well tested)
  • object (not well tested)
  • track (not well tested)
  • worker (not well tested)
  • video (not well tested)

https://developer.mozilla.org/en-US/docs/Web/HTML/Preloading_content

Integration in your Page

the polyfill and the invoke script are seperated

    <script src="/dist/preload-polyfill.min.js"></script>
    <script src="/dist/preload-polyfill-invoke.min.js"></script>

additionally you need an inline script (for browsers that are preload capable, preloading stuff could be faster than loading an external sync script, and you would miss the load event)

    <script>/dist/preload-polyfill-inline.min.js</script>

Preloading Stuff

simply use it as follows:

<link rel="preload" as="script" href="jquery.js" />

Additional Features

beware those are not spec compliant features

critical

those resources will be fetched non blocking, but executed first in order they appear

<link rel="preload" critical as="script" href="jquery.js" />

fonts

to preload fonts correctly you have to set a name property on the links

<link rel="preload" name="FontName" weight="bold" as="font" crossorigin type="font/woff2" href="font.woff2" />

module

those resources will only be fetched if browser understands es6

<link rel="preload" module as="script" href="app.es6.js" />

nomodule

those resources will only be fetched if browser cant understand es6

<link rel="nomodule" as="script" href="app.legacy.js" />

AllScriptsExecuted Event

window.onload can be fired even if not all preloaded scripts are executed, therefore we dispatch an event AllScriptsExecuted which indicates all preloaded stuff is executed too.

Development

$ npm start

now visit https://localhost:5000

TODOS

Thanks

If you find any bugs or have a feature request, please open an issue on github!

The npm package download data comes from npm's download counts api and package details come from npms.io.