fastmatter

A fast frontmatter parser. Supports both string and stream inputs.

Usage

Given a document foo.md containing YAML frontmatter and content:

---
title: Hello, World!
tags: [ foo, bar, baz ]
---
Lorem ipsum dolor sit amet consectetur adipisicing elit.

…we can parse this document as a string, via fastmatter(string):

const fastmatter = require('fastmatter')
const fs = require('fs')

fs.readFile('foo.md', 'utf8', function (error, data) {
  if (error) {
    throw error
  }
  console.log(fastmatter(data))
  /* =>
   * {
   *   attributes: {
   *     title: 'Hello, World!',
   *     tags: [ 'foo', 'bar', 'baz' ]
   *   },
   *   body: 'Lorem ipsum dolor sit amet consectetur adipisicing elit.'
   * }
   */
})

…or as a stream, via fastmatter.stream([callback]):

const fastmatter = require('fastmatter')
const fs = require('fs')
const concat = require('concat-stream')

fs.createReadStream('foo.md').pipe(
  fastmatter.stream(function (attributes) {
    console.log(attributes)
    /* =>
     * {
     *   title: 'Hello, World!',
     *   tags: [ 'foo', 'bar', 'baz' ]
     * }
     */
    this.pipe(
      concat(function (body) {
        console.log(body.toString())
        //=> Lorem ipsum dolor sit amet consectetur adipisicing elit.
      })
    )
  })
)

callback is called with the frontmatter attributes, while the document body is simply passed through the stream. Also note that the this context of callback is the stream itself; this is useful if we want to change the flow of the stream depending on the parsed attributes.

API

const fastmatter = require('fastmatter')

fastmatter(string)

Parses the string and returns the parsed frontmatter attributes and document body.

fastmatter.stream([callback])

Calls callback with the parsed frontmatter attributes. The this context of callback is the stream itself. The document body is passed through the stream.

Installation

Install via yarn:

$ yarn add fastmatter

Or npm:

$ npm install --save fastmatter

License

MIT