markdown-it-link-attributes

Link attributes plugin for markdown-it markdown parser.

Install

node.js, browser:

npm install markdown-it-link-attributes --save
bower install markdown-it-link-attributes --save

Use

Basic Configuration

You can pass an object with an attrs property. Each link parsed with this config will have the passed attributes.

var md = require('markdown-it')()
var mila = require('markdown-it-link-attributes')

md.use(mila, {
  attrs: {
    target: '_blank',
    rel: 'noopener'
  }
})

var result = md.render('[Example](https://example.com')

result // <a href="https://example.com" target="_blank" rel="noopener">Example</a>

If the linkify option is set to true on markdown-it, then the attributes will be applied to plain links as well.

var md = require('markdown-it')({
  linkify: true
})

md.use(mila, {
  target: '_blank',
  rel: 'noopener'
})

var html = md.render('foo https://google.com bar')
html // <p>foo <a href="https://google.com" target="_blank" rel="noopener">https://google.com</a> bar</p>

Applying classes

You can apply a class to a link by using a class or a className property. Either one will work, but use only one, not both.

md.use(mila, {
  attrs: {
    class: 'my-class'
  }
})

// or
md.use(mila, {
  attrs: {
    className: 'my-class'
  }
})

Conditionally apply attributes

You can choose to test a links 'href' against either a rege pattern or a custom function. If a pattern or function are specified, then only if the relevant option returns true will the attributes be applied. You should only define a pattern OR a function, not both. If both a pattern AND function are defined, only the function will be tested (pattern will be ignored).

To use a RegExp

md.use(mila, {
  pattern: /^https:/,
  attrs: {
    target: '_blank',
    rel: 'noopener'
  }
})

To use a function

md.use(mila, {
  function: (href, config) => { return href.startsWith('https:') },
  attrs: {
    target: '_blank',
    rel: 'noopener'
  }
})

var matchingResult = md.render('[Matching Example](https://example.com')
var ignoredResult = md.render('[Not Matching Example](http://example.com')

matchingResult // <a href="https://example.com" target="_blank" rel="noopener">Matching Example</a>
ignoredResult // <a href="http://example.com">Not Matching Example</a>

Multiple Configurations

Alternatively, you can pass an Array of configurations. The first pattern to match will be applied to the link.

md.use(mila, [{
  pattern: /^https?:\/\//,
  attrs: {
    class: 'external-link'
  }
}, {
  pattern: /^\//,
  attrs: {
    class: 'absolute-link'
  }
}, {
  pattern: /blue/,
  attrs: {
    class: 'link-that-contains-the-word-blue'
  }
}])

var externalResult = md.render('[external](https://example.com')
var absoluteResult = md.render('[absolute](/some-page')
var blueResult = md.render('[blue](relative/link/with/blue/in/the/name')

externalResult // <a href="https://example.com" class="external-link">external</a>
absoluteResult // <a href="/some-page" class="absolute-link">absolute</a>
blueResult // <a href="relative/link/with/blue/in/the/name" class="link-that-contains-the-word-blue">blue</a>

If multiple patterns match, the first configuration to match will be used.

// This matches both the "starts with http or https" rule and the "contains the word blue" rule.
// Since the http/https rule was defined first, that is the configuration that is used.
var result = md.render('[external](https://example.com/blue')

result // <a href="https://example.com/blue" class="external-link">external</a>

Usage in the browser

Differences in browser. If you load script directly into the page, without a package system, the module will add itself globally as window.markdownitLinkAttributes. You need to load dist/markdown-it-link-attributes.min.js, if you don't use a build system.

Testing

This plugin is tested against the latest version of markdown-it

License

MIT