ISO-Share/node_modules/zero-md/README.md

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2024-03-27 14:37:57 +01:00
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# <zero-md>
> Ridiculously simple zero-config markdown displayer
A native markdown-to-html web component based on
[Custom Elements V1 specs](https://www.w3.org/TR/custom-elements/) to load and display an external
MD file. Under the hood, it uses [Marked](https://github.com/markedjs/marked) for super-fast
markdown transformation, and [Prism](https://github.com/PrismJS/prism) for feature-packed syntax
highlighting - automagically rendering into its own self-contained shadow DOM container, while
encapsulating implementation details into one embarassingly easy-to-use package.
**NOTE: This is the V2 branch. If you're looking for the older version, see the
[V1 branch](https://github.com/zerodevx/zero-md/tree/v1).**
Featuring:
- [x] Automated hash-link scrolls
- [x] Built-in FOUC prevention
- [x] Automatically rewrite URLs relative to `src`
- [x] Automatically re-render when `src` changes
- [x] Automatically re-render when inline markdown or style template changes
- [x] Support for >200 code languages with detection for unhinted code blocks
- [x] Easy styling mechanism
- [x] Highly extensible
Documentation: https://zerodevx.github.io/zero-md/
**NOTE: Your markdown file(s) needs to be hosted! Browsers don't generally allow javascript to
access files on the local hard drive because of security concerns. Standard
[CORS](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS) rules apply.**
## Installation
### Load via CDN (recommended)
`zero-md` is designed to be zero-config with good defaults. For most use-cases, just importing the
script from CDN and consuming the component directly should suffice.
```html
<head>
...
<!-- Import element definition -->
<script
type="module"
src="https://cdn.jsdelivr.net/gh/zerodevx/zero-md@2/dist/zero-md.min.js"
></script>
...
</head>
<body>
...
<!-- Profit! -->
<zero-md src="/example.md"></zero-md>
...
</body>
```
Latest stable: `https://cdn.jsdelivr.net/gh/zerodevx/zero-md@2/dist/zero-md.min.js`
Latest beta: `https://cdn.jsdelivr.net/npm/zero-md@next/dist/zero-md.min.js`
### Install in web projects
Install package with `npm` or `yarn`. Note that you'll need [Node.js](https://nodejs.org/)
installed.
```
$ npm install --save zero-md
```
Import the class, register the element, and use anywhere.
```js
// Import the element definition
import ZeroMd from 'zero-md'
// Register the custom element
customElements.define('zero-md', ZeroMd)
// Render anywhere
app.render(`<zero-md src=${src}></zero-md>`, target)
```
Or load the distribution directly in HTML.
```html
<script type="module" src="/node_modules/zero-md/dist/zero-md.min.js"></script>
...
<zero-md src="example.md"></zero-md>
```
## Basic Usage
### Display an external markdown file
```html
<!-- Simply set the `src` attribute and win -->
<zero-md src="https://example.com/markdown.md"></zero-md>
```
At its most basic, `<zero-md>` loads and displays an external MD file with **default stylesheets** -
a Github-themed stylesheet paired with a light-themed one for code blocks, just like what you see in
these docs. So internally, the above code block is semantically equivalent to the one below:
```html
<zero-md src="https://example.com/markdown.md">
<!-- By default, this style template gets loaded -->
<template>
<link
rel="stylesheet"
href="https://cdn.jsdelivr.net/gh/sindresorhus/github-markdown-css@4/github-markdown.min.css"
/>
<link
rel="stylesheet"
href="https://cdn.jsdelivr.net/gh/PrismJS/prism@1/themes/prism.min.css"
/>
</template>
</zero-md>
```
### Using your own styles
To override the default theme, supply your own style template.
```html
<zero-md src="https://example.com/markdown.md">
<!-- Wrap with a <template> tag -->
<template>
<!-- Define your own styles inside a `<style>` tag -->
<style>
h1 {
color: red;
}
...;
</style>
</template>
</zero-md>
```
### Or your own stylesheets
```html
<zero-md src="https://example.com/markdown.md">
<!-- Wrap with a <template> tag -->
<template>
<!-- Load external stylesheets with a `<link rel="stylesheet">` tag -->
<link rel="stylesheet" href="markdown-styles.css" />
<link rel="stylesheet" href="highlight-styles.css" />
</template>
</zero-md>
```
### Or both
```html
<zero-md src="https://example.com/markdown.md">
<template>
<!-- The CSS load order is respected -->
<link rel="stylesheet" href="markdown-styles.css" />
<style>
h1 {
color: red;
}
</style>
<link rel="stylesheet" href="highlight-styles.css" />
<style>
code {
background: yellow;
}
</style>
</template>
</zero-md>
```
### Write markdown inline
You can pass in your markdown inline too.
```html
<!-- Do not set the `src` attribute -->
<zero-md>
<!-- Write your markdown inside a `<script type="text/markdown">` tag -->
<script type="text/markdown">
# **This** is my [markdown](https://example.com)
</script>
</zero-md>
```
By default, `<zero-md>` first tries to render `src`. If `src` is falsy (undefined, file not found,
empty file etc), it **falls-back** to the contents inside the `<script type="text/markdown">` tag.
### Put it all together
```html
<zero-md src="https://example.com/markdown.md">
<template>
<link rel="stylesheet" href="markdown-styles.css" />
<style>
h1 {
color: red;
}
</style>
<link rel="stylesheet" href="highlight-styles.css" />
<style>
code {
background: yellow;
}
</style>
</template>
<script type="text/markdown">
This is the fall-back markdown that will **only show** when `src` is falsy.
</script>
</zero-md>
```
## API
Advanced usage: https://zerodevx.github.io/zero-md/advanced-usage/
Attributes and helpers: https://zerodevx.github.io/zero-md/attributes-and-helpers/
Configuration: https://zerodevx.github.io/zero-md/configuration/
## Migrating from V1 to V2
1. Support for `<xmp>` tag is removed; use `<script type="text/markdown">` instead.
<!-- prettier-ignore -->
```html
<!-- Previous -->
<zero-md>
<template>
<xmp>
# `This` is my [markdown](example.md)
</xmp>
</template>
</zero-md>
<!-- Now -->
<zero-md>
<!-- No need to wrap with <template> tag -->
<script type="text/markdown">
# `This` is my [markdown](example.md)
</script>
</zero-md>
<!-- If you need your code to be pretty, -->
<zero-md>
<!-- Set `data-dedent` to opt-in to dedent the text during render -->
<script type="text/markdown" data-dedent>
# It is important to be pretty
So having spacing makes me happy.
</script>
</zero-md>
```
2. Markdown source behaviour has changed. Think of `<script type="text/markdown">` as a "fallback".
<!-- prettier-ignore -->
```html
<!-- Previous -->
<zero-md src="will-not-render.md">
<template>
<xmp>
# This has first priority and will be rendered instead of `will-not-render.md`
</xmp>
</template>
<zero-md>
<!-- Now -->
<zero-md src="will-render-unless-falsy.md">
<script type="text/markdown">
# This will NOT be rendered _unless_ `src` resolves to falsy
</script>
</zero-md>
```
3. The `css-urls` attribute is deprecated. Use `<link rel="stylesheet">` instead.
<!-- prettier-ignore -->
```html
<!-- Previous -->
<zero-md src="example.md" css-urls='["/style1.css", "/style2.css"]'><zero-md>
<!-- Now, this... -->
<zero-md src="example.md"></zero-md>
<!-- ...is actually equivalent to this -->
<zero-md src="example.md">
<template>
<!-- These are the default stylesheets -->
<link
rel="stylesheet"
href="https://cdn.jsdelivr.net/gh/sindresorhus/github-markdown-css@4/github-markdown.min.css"
/>
<link
rel="stylesheet"
href="https://cdn.jsdelivr.net/gh/PrismJS/prism@1/themes/prism.min.css"
/>
</template>
</zero-md>
<!-- So, to apply your own external stylesheets... -->
<zero-md src="example.md">
<!-- ...you overwrite the default template -->
<template>
<!-- Use <link> tags to reference your own stylesheets -->
<link rel="stylesheet" href="/style1.css" />
<link rel="stylesheet" href="/style2.css" />
<!-- You can even apply additional styles -->
<style>
p {
color: red;
}
</style>
</template>
</zero-md>
<!-- If you like the default stylesheets but wish to apply some overrides -->
<zero-md src="example.md">
<!-- Set `data-merge` to "append" to apply this template AFTER the default template -->
<!-- Or "prepend" to apply this template BEFORE -->
<template data-merge="append">
<style>
p {
color: red;
}
</style>
</template>
</zero-md>
```
4. The attributes `marked-url` and `prism-url` are deprecated. To load `marked` or `prism` from
another location, simply load their scripts _before_ importing `zero-md`.
```html
<head>
...
<script defer src="/lib/marked.js"></script>
<script defer src="/lib/prism.js"></script>
<script type="module" src="/lib/zero-md.min.js"></script>
</head>
```
5. The global config object has been renamed from `ZeroMd.config` to `ZeroMdConfig`.
```html
<!-- Previous -->
<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-loader.js"></script>
<script>
window.ZeroMd = {
config: {
cssUrls: ['/styles/my-markdown-theme.css', '/styles/my-highlight-theme.css']
}
}
</script>
<script
type="module"
src="https://cdn.jsdelivr.net/gh/zerodevx/zero-md@1/src/zero-md.min.js"
></script>
<!-- Now -->
<script>
window.ZeroMdConfig = {
cssUrls: ['/styles/my-markdown-theme.css', '/styles/my-highlight-theme.css']
}
</script>
<script
type="module"
src="https://cdn.jsdelivr.net/gh/zerodevx/zero-md@2/dist/zero-md.min.js"
></script>
```
6. The convenience events `zero-md-marked-ready` and `zero-md-prism-ready` are removed and **will no
longer fire**. Instead, the `zero-md-ready` event guarantees that everything is ready, and that
render can begin.
## Contributing
### Noticed a bug? Have a feature request?
Open a new [issue](https://github.com/zerodevx/zero-md/issues) in the Github repo, or raise a
[PR](https://github.com/zerodevx/zero-md/pulls)! I'd be stoked to accept any contributions!
### Development
Standard Github [contribution workflow](https://github.com/firstcontributions/first-contributions)
applies.
#### Run the dev server
```
$ npm run dev
```
Point your browser to `http://localhost:8000` and you should see the test suite running.
#### Testing
Tests are browser-based and run on [Mocha](https://mochajs.org/) with
[Chai](https://www.chaijs.com/) asserts. If you're adding a new feature or bugfixing, please add the
corresponding regression test into `test/index.spec.js` accordingly.
#### Format and lint
```
$ npm run format
$ npm run lint
```
Formatting and linting by [prettier](https://github.com/prettier/prettier) and
[eslint](https://github.com/eslint/eslint) respectively.
#### Making changes to docs
Documentation is in the `/docs` folder in the form of `readme.md` files, and published on
[Github Pages](https://pages.github.com/). This setup is based on
[`zero-md-docs`](https://github.com/zerodevx/zero-md-docs).
To make changes to docs, simply raise a PR on any `readme.md` files should suffice.
## Changelog
Check out the [releases](https://github.com/zerodevx/zero-md/releases) page.
## License
ISC
## Acknowledgement
A big thank you to the following contributors and sponsors! :pray:
### Contributors
<!-- prettier-ignore -->
<kbd>[<img src="https://github.com/alifeee.png" width="60px;"/>](https://github.com/alifeee)</kbd> <kbd>[<img src="https://github.com/EmilePerron.png" width="60px;"/>](https://github.com/EmilePerron)</kbd> <kbd>[<img src="https://github.com/bennypowers.png" width="60px;"/>](https://github.com/bennypowers)</kbd> <kbd>[<img src="https://github.com/TheUnlocked.png" width="60px;"/>](https://github.com/TheUnlocked)</kbd> <kbd>[<img src="https://github.com/ernsheong.png" width="60px;"/>](https://github.com/ernsheong)</kbd>
### Sponsors
<!-- prettier-ignore -->
<kbd>[<img src="https://github.com/RootofalleviI.png" width="60px;"/>](https://github.com/RootofalleviI)</kbd><kbd>[<img src="https://github.com/alifeee.png" width="60px;"/>](https://github.com/alifeee)</kbd>