markdown-stream-utils

Utility functions for processing markdown files using object mode streams. Used by markdown-styles and by ghost-render.

Changelog

v1.2.0: Updated highlight.js and other dependencies, thanks @omnibs!

v1.1.0: made highlight apply the syntax highlighting for the specific language if available in highlight.js. Added md.marked and added opts to md.convertMd().

API

Getting started

All of the markdown-stream-utils functions expect to receive objects representing each markdown file. The files should have three properties:

• path: a path to the original filename
• stat: fs.stats object
• contents: the contents of the file as a string

Here's a full example of using markdown-stream-utils, with some helpers from [pipe-iterators](https://github.com/mixu/pipe-iterators):

var pi = require('pipe-iterators'),
    md = require('markdown-stream-utils');

pi.fromArray([ __dirname + '/foo.md', __dirname + '/bar.md' ])
  .pipe(pi.thru.obj(function(file, enc, onDone) {
    var stat = fs.statSync(file);
    if (stat.isFile()) {
      this.push({
        path: file,
        stat: stat,
        contents: fs.readFileSync(file).toString()
      });
    }
    onDone();
  }))
  .pipe(md.parseHeader())
  .pipe(md.parseMd())
  .pipe(md.highlightJS())
  .pipe(md.convertMd())
  .pipe(pi.toArray(function(results) {
    console.log(results);
  }));

parseHeader()

.pipe(md.parseHeader())

Parses header sections in markdown files. For example, given a object with the following content field:

title: Hello world
author: foo
---
# Heading
...

it will augment the existing object with two new fields: title and author with the specified values.

The header section may be written in either JSON or YAML. There must be at least three - characters that separate the header from the rest of the content (on a single line). Headers may also have a beginning delimiter, e.g.:

---
title: Hello world
---
# Heading

The header section will be removed from contents, so that only the markdown content after the --- will be kept in the contents key.

You can customize the contents field as well as the destination of the metadata. To set the contents field name, pass in an options hash with contentsKey. To set the metadata storage key, pass the key name in metadataKey; if this is false (default), the metadata is merged; if it is set then the metadata is stored under a subkey.

parseMd()

pipe(md.parseMd())

Given an object with a contents field, executes marked.lexer() on the contents field. The new value is the lexer tree from marked.

highlight()

pipe(md.highlight())

Iterates over the lexer tree from parseMd, and executes the highlight.js highlighter on each code block.

You can add support for additional languages by passing a custom callback with the signature function(code, lang) {}, which should return either a HTML string containing the highlighted version of the code, or false if you want to run highlight.js on the code block.

Note that you will need a highlight.js CSS style sheet in your final output so that the styling is visible.

annotateMdHeadings()

pipe(md.annotateMdHeadings())

Iterates over the lexer tree from parseMd. Annotates every heading with an id, so that when converted to HTML the headings can be targeted via links. An array all the headings is produced under headings. The value is an array of lexer tokens with an id property.

For example:

# Test
foo

results in the input object being augmented with:

{ headings: [ { id: 'test', text: 'foo', type: 'heading', depth: 1 } ] }

By default, the markdown tokens are read from the contents key on the input object, and written to the headings key.

You can customize the keys used by passing in an options hash. The contentsKey property controls the key from which the lexer tree is read, and the headingsKey controls the key to which the headings are written.

convertMd(opts)

pipe(md.convertMd())

Constructs a new parser using marked default options, overriding with the values from opts where specified (e.g. opts.renderer can be used to override the renderer).

Given an object with a contents field, executes Parser.parse() on the contents field. The new value is the HTMLs from marked.

marked

console.log(md.marked);

A reference to the marked library, in case you need to construct a marked.Renderer for convertMd.