GitbookIO/kramed

kramed

A full-featured markdown parser and compiler, written in JavaScript. Built for speed.

Install

npm install kramed --save

Why fork marked ?

marked hasn't been evolving as much as it could be lately and due to our needs with GitBook, we need features such as robust mathjax support and want to strive closer to the rising kramdown standard.

Usage

Minimal usage:

var kramed = require('kramed');
console.log(kramed('I am using __markdown__.'));
// Outputs: <p>I am using <strong>markdown</strong>.</p>

Example setting options with default values:

var kramed = require('kramed');
kramed.setOptions({
  renderer: new kramed.Renderer(),
  gfm: true,
  tables: true,
  breaks: false,
  pedantic: false,
  sanitize: true,
  smartLists: true,
  smartypants: false
});

console.log(kramed('I am using __markdown__.'));

kramed(markdownString [,options] [,callback])

markdownString

Type: string

String of markdown source to be compiled.

options

Type: object

Hash of options. Can also be set using the kramed.setOptions method as seen above.

callback

Type: function

Function called when the markdownString has been fully parsed when using async highlighting. If the options argument is omitted, this can be used as the second argument.

Options

highlight

Type: function

A function to highlight code blocks. The first example below uses async highlighting with node-pygmentize-bundled, and the second is a synchronous example using highlight.js:

var kramed = require('kramed');

var markdownString = '```js\n console.log("hello"); \n```';

// Async highlighting with pygmentize-bundled
kramed.setOptions({
  highlight: function (code, lang, callback) {
    require('pygmentize-bundled')({ lang: lang, format: 'html' }, code, function (err, result) {
      callback(err, result.toString());
    });
  }
});

// Using async version of kramed
kramed(markdownString, function (err, content) {
  if (err) throw err;
  console.log(content);
});

// Synchronous highlighting with highlight.js
kramed.setOptions({
  highlight: function (code) {
    return require('highlight.js').highlightAuto(code).value;
  }
});

console.log(kramed(markdownString));

highlight arguments

code

Type: string

The section of code to pass to the highlighter.

lang

Type: string

The programming language specified in the code block.

callback

Type: function

The callback function to call when using an async highlighter.

renderer

Type: object Default: new Renderer()

An object containing functions to render tokens to HTML.

Overriding renderer methods

The renderer option allows you to render tokens in a custom manor. Here is an example of overriding the default heading token rendering by adding an embedded anchor tag like on GitHub:

var kramed = require('kramed');
var renderer = new kramed.Renderer();

renderer.heading = function (text, level) {
  var escapedText = text.toLowerCase().replace(/[^\w]+/g, '-');

  return '<h' + level + '><a name="' +
                escapedText +
                 '" class="anchor" href="#' +
                 escapedText +
                 '"><span class="header-link"></span></a>' +
                  text + '</h' + level + '>';
},

console.log(kramed('# heading+', { renderer: renderer }));

This code will output the following HTML:

<h1>
  <a name="heading-" class="anchor" href="#heading-">
    <span class="header-link"></span>
  </a>
  heading+
</h1>

Block level renderer methods

• code(string code, string language)
• blockquote(string quote)
• html(string html)
• heading(string text, number level)
• hr()
• list(string body, boolean ordered)
• listitem(string text)
• paragraph(string text)
• table(string header, string body)
• tablerow(string content)
• tablecell(string content, object flags)

flags has the following properties:

{
    header: true || false,
    align: 'center' || 'left' || 'right'
}

Inline level renderer methods

• strong(string text)
• em(string text)
• codespan(string code)
• br()
• del(string text)
• link(string href, string title, string text)
• image(string href, string title, string text)

gfm

Type: boolean Default: true

Enable GitHub flavored markdown.

tables

Type: boolean Default: true

Enable GFM tables. This option requires the gfm option to be true.

breaks

Type: boolean Default: false

Enable GFM line breaks. This option requires the gfm option to be true.

pedantic

Type: boolean Default: false

Conform to obscure parts of markdown.pl as much as possible. Don't fix any of the original markdown bugs or poor behavior.

sanitize

Type: boolean Default: false

Sanitize the output. Ignore any HTML that has been input.

smartLists

Type: boolean Default: true

Use smarter list behavior than the original markdown. May eventually be default with the old behavior moved into pedantic.

smartypants

Type: boolean Default: false

Use "smart" typograhic punctuation for things like quotes and dashes.

Access to lexer and parser

You also have direct access to the lexer and parser if you so desire.

var tokens = kramed.lexer(text, options);
console.log(kramed.parser(tokens));

var lexer = new kramed.Lexer(options);
var tokens = lexer.lex(text);
console.log(tokens);
console.log(lexer.rules);

CLI

$ kramed -o hello.html
hello world
^D
$ cat hello.html
<p>hello world</p>

Philosophy behind kramed

The point of kramed was to create a markdown compiler where it was possible to frequently parse huge chunks of markdown without having to worry about caching the compiled output somehow...or blocking for an unnecesarily long time.

kramed is very concise and still implements all markdown features. It is also now fully compatible with the client-side.

kramed more or less passes the official markdown test suite in its entirety. This is important because a surprising number of markdown compilers cannot pass more than a few tests. It was very difficult to get kramed as compliant as it is. It could have cut corners in several areas for the sake of performance, but did not in order to be exactly what you expect in terms of a markdown rendering. In fact, this is why kramed could be considered at a disadvantage in the benchmarks above.

Along with implementing every markdown feature, kramed also implements GFM features.

Benchmarks

node v0.8.x

$ node test --bench
kramed completed in 3411ms.
kramed (gfm) completed in 3727ms.
kramed (pedantic) completed in 3201ms.
robotskirt completed in 808ms.
showdown (reuse converter) completed in 11954ms.
showdown (new converter) completed in 17774ms.
markdown-js completed in 17191ms.

Kramed is now faster than Discount, which is written in C.

For those feeling skeptical: These benchmarks run the entire markdown test suite 1000 times. The test suite tests every feature. It doesn't cater to specific aspects.

Pro level

You also have direct access to the lexer and parser if you so desire.

var tokens = kramed.lexer(text, options);
console.log(kramed.parser(tokens));

var lexer = new kramed.Lexer(options);
var tokens = lexer.lex(text);
console.log(tokens);
console.log(lexer.rules);

$ node
> require('kramed').lexer('> i am using kramed.')
[ { type: 'blockquote_start' },
  { type: 'paragraph',
    text: 'i am using kramed.' },
  { type: 'blockquote_end' },
  links: {} ]

Running Tests & Contributing

If you want to submit a pull request, make sure your changes pass the test suite. If you're adding a new feature, be sure to add your own test.

The kramed test suite is set up slightly strangely: test/new is for all tests that are not part of the original markdown.pl test suite (this is where your test should go if you make one). test/original is only for the original markdown.pl tests. test/tests houses both types of tests after they have been combined and moved/generated by running node test --fix or kramed --test --fix.

In other words, if you have a test to add, add it to test/new/ and then regenerate the tests with node test --fix. Commit the result. If your test uses a certain feature, for example, maybe it assumes GFM is not enabled, you can add .nogfm to the filename. So, my-test.text becomes my-test.nogfm.text. You can do this with any kramed option. Say you want line breaks and smartypants enabled, your filename should be: my-test.breaks.smartypants.text.

To run the tests:

cd kramed/
node test

TODO

• Refactor code to have greater modularity
• Strive for kramdown compatibility (it's the new standard)
• Improve, improve, improve ...

Contribution and License Agreement

If you contribute code to this project, you are implicitly allowing your code to be distributed under the MIT license. You are also implicitly verifying that all code is your original work. </legalese>

License

Marked: Copyright (c) 2011-2014, Christopher Jeffrey. (MIT License) Kramed: Copyright (c) 2014, Aaron O'Mullan. (MIT Licensed)

See LICENSE for more info.