README

be-based

be-based is a package that allows a DOM document fragment filled with relative URL paths, to be adjusted based on a base URL.

The syntax:

<template be-based='{
    "rules": [
        {
            "selector": "a",
            "attr": "href",
            "ifNot": "^(http|https)",
            "baseHref": "https://www.supremecourt.gov/about/"
        }
    ]
}'>
    <a href="biographies.aspx#SOConnor">O'Connor, Sandra Day</a>
</template>

be-based transforms the template to:

<template is-based='{
    "rules": [
        {
            "selector": "a",
            "attr": "href",
            "ifNot": "^(http|https)",
            "baseHref": "https://www.supremecourt.gov/about/"
        }
    ]
}'>
    <a href="https://www.supremecourt.gov/about/biographies.aspx#SOConnor">O'Connor, Sandra Day</a>
</template>

When?

The only question is "when does this happen"? This packages allows it to happen in two places, but hopefully two additional places will be added in the future.

During Template Instantiation

The package provides an entry point (trPlugin.js) to allow this to be done during template instantiation.

In particular, it can be incorporated via a single line declarative config setting into a DTR-based template instantiation.

But it is a "non-blocking" dependency. If the library hasn't been loaded by the time the template instantiation commences, Arazorik ez, let the second avenue for the transformation happen in the live DOM:

As a custom attribute / decorator / behavior

be-based is one of a growing family of be-decorated web component based custom attributes / behaviors / decorators / directives.

By referencing be-based.js, elements with attribute be-based will be discovered and transformed.

Or we can refence index.js, which loads both trPlugin.js and be-based.js in parallel.

The element be-based can decorate is not limited to template elements. It can be applied to any DOM element.

During Template Instantiation, But Programmatically

If using a non trans-render based template instantiation library, the following api allows the rules to be processed programmatically.

import { BeBasedVirtualProps } from 'be-based/types';

async function processBeBasedRules(props: BeBasedVirtualProps | undefined, target: Element){
    if(props === undefined) return;
    const {processRules} = await import('be-based/processRules.js');
    processRules({proxy: target, rules: props.rules});
}

As a cloudflare HTMLRewriter Class [TODO]

As a service worker helper [TODO]

W3C willing.

Usage no npm install needed!