scriptswitch v0.1.5

scriptswitch v0.1.5

Super simple (and tiny, 700 bytes gzipped) conditional script loading manager for browsers and NodeJS.

Handles all the standard script attributes, e.g. async, defer, etc.

Supports asynchronous loading or sequenced synchronous loading for scripts that are dependent on other scripts.

Works as far back as IE 10, Safari 5.1, Firefox 8, Chrome 10.

Installation

npm install scriptswitch

Use the file scriptswitch.js in the browser directory for browsers. You MUST provide the id "scriptswitch".

<script id="scriptswitch" src="scriptswitch.js"></script>

Use regular NodeJS syntax for NodeJS:

const scriptswitch = require("scriptswitch");

Usage

For browsers, just pass a dynamically built configuration object into scriptswitch. Each property should be a path to a script file. If the value is null, the script will not be loaded. Otherwise, the configuration options you provide will be used to load the script.

scriptswitch({
	"core.js": {
		async:false
	},
	"patches.js": (() => {
		if(<some condition under which patches are needed>) {
			return {
				async:false,
				onload:() => console.warn(`Had to load ${ev.target.src}`)
			}
		}
		return null;
	})(),
	"lazyloads.js": {
		async: true
	},
	"secondary.js": {} // assumes standard loading, i.e. async:false
})

The async:false scripts complete loading in the order provided. Other scripts will complete laoding based on size, network performance, etc.

scriptswitch returns an array of Promise for all the loading scripts, i.e:

Promise.all(scriptswitch(<config object>)).then(arrayOfScriptDOMElements => ...);

For NodeJS, provide an additional options argument {scope:<usually 'this'>} and for each script add a property as with the value being the variable to which you would like the script export bound, e.g.

scriptswitch({
		"util": {
			as:"u"; // same as 'var u = require("util")'
		}
	},
	{scope:this})

Under the hood, all NodeJS scripts load synchronously; however, those marked as async:true will fire their onload event handlers asynchronously.

Developed and Tested With

Eclipse, Mocha, Chai, and Browserstack.

Release History (reverse chronological order)

2018-08-07 v0.1.5 Older browser compatibility changes.

2018-08-06 v0.1.4 Documentation corrections.

2018-08-06 v0.1.3 Added NodeJS support.

2018-08-06 v0.1.2 Added support for older browsers not having Promises.

2018-08-05 v0.1.1 Documentation enhancements.

2018-08-05 v0.1.0 First public release.

License

MIT License

Copyright (c) 2018 Simon Y. Blackwell, AnyWhichWay, LLC

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.