@jsenv/url-meta

url-meta

@jsenv/url-meta allows to associate value to urls using pattern matching.

import { urlToMeta } from "@jsenv/url-meta"

// conditionally associates url and values
const structuredMetaMap = {
  color: {
    "file:///*": "black",
    "file:///*.js": "red",
  },
}
const urlToColor = (url) => {
  return urlToMeta({ url, structuredMetaMap }).color
}
console.log(`file.json color is ${urlToColor("file:///file.json")}`)
console.log(`file.js color is ${urlToColor("file:///file.js")}`)

Code above logs

file.json color is black
file.js color is red

Common pattern example

pattern	Description
**/	Everything
*/**/	Inside a directory
**/.*/	Inside directory starting with a dot
**/node_modules/	Inside any node_modules directory
node_modules/	Inside root node_modules directory
**/*.map	Ending with .map
**/*.test.*	Contains .test.
*	Inside the root directory only
*/*	Inside a directory of depth 1

Read more at ./docs/pattern_matching.md

metaMap and structuredMetaMap

metaMap and structuredMetaMap below translates into: "files are visible except thoose in .git/ directory"

const metaMap = {
  "**/*": { visible: true },
  "**/.git/": { visible: false },
}
const structuredMetaMap = {
  visible: {
    "**/*/": true,
    "**/.git/": false,
  },
}

structuredMetaMap allows to group patterns per property which are easier to read and compose. All keys in structuredMetaMap must be resolved against an url, this can be done with normalizeStructuredMetaMap.

normalizeStructuredMetaMap

normalizeStructuredMetaMap is a function resolving structuredMetaMap keys against an url.

import { normalizeStructuredMetaMap } from "@jsenv/url-meta"

const structuredMetaMapNormalized = normalizeStructuredMetaMap(
  {
    visible: {
      "**/*/": true,
      "**/.git/": false,
    },
  },
  "file:///Users/directory/",
)
console.log(JSON.stringify(structuredMetaMapNormalized, null, "  "))

{
  "visible": {
    "file:///Users/directory/**/*/": true,
    "file:///Users/directory/**/.git/": false
  }
}

Installation

npm install @jsenv/url-meta

Can be used in browsers and Node.js.

Changelog

36.2.0

• Change internal packages structure
• Ensure document.adoptedStyleSheets, globalThis and regeneratorRuntime polyfill injection in js classic