remark-shortcodes

A custom Markdown syntax parser for remark that adds support for shortcodes.

What are shortcodes? They are a way to provide hooks for macros and/or template partials inside a markdown file. They consist of start & end blocks, in between which the shortcode has a name defined and an optional set of key:value attributes in HTML style. They can look like this:

The example below uses the default start & end blocks that
this parser ships with:

[[ MailchimpForm id="chfk2" ]]

But they are configurable, so if you're coming from Hugo say,
you can set them as such:

{{< MailchimpForm id="chfk2" >}}

Why use them? Because sometimes you'd like to insert content inline without copy pasting raw HTML in to your Markdown file. The copy paste approach means that hard-to-modify code is littered throughout your content and is therefore very hard to maintain; whereas the shortcode approach can result in a partial being updated in only one place.

Both Wordpress & Hugo have support for shortcodes; this parser's implementation is much closer to Wordpress's, as it does not support inner content or nested shortcodes like Hugo does - but can actually be used for the simpler partials. It was made for my use, but if you'd like to extend it to support more cases, please feel free! Everyone is welcome.

AST Block: Shortcode

Shortcode (Node) is a simple node that has an identifier and an optional object with string values, respresenting the attributes parsed.

interface Shortcode <: Node {
  type: "shortcode";
  identifier: string;
  attributes: { key: string, ...}
}

For example, the following markdown:

[[ MailchimpForm id="chfk2" ]]

Yields:

{
  "type": "shortcode",
  "identifier": "MailchimpForm",
  "attributes": { "id": "chfk2" }
}

Installation

npm:

npm install --save remark-shortcodes

Usage

Say example.js looks as follows:

var unified = require('unified');
var parse = require('remark-parse');
var shortcodes = require('remark-shortcodes');

var markdown = 'Example paragraph\n\n{{> MailchimpForm id="chfk2" <}}'

var tree = unified()
  .use(parse)
  // Plugin inserted below, with custom options for start/end blocks.
  .use(shortcodes, {startBlock: "{{>", endBlock: "<}}"})
  // Turn off position output for legibility below.
  .data('settings', {position: false})
  .parse(markdown);

console.dir(tree, {depth: null});

Running node example yields:

{
  "type": "root",
  "children": [
    {
      "type": "paragraph",
      "children": [{ "type": "text", "value": "Example paragraph" }]
    },
    {
      "type": "shortcode",
      "identifier": "MailchimpForm",
      "attributes": { "id": "chfk2" }
    }
  ]
}

Say example2.js looks as follows:

var unified = require('unified');
var parse = require('remark-parse');
var shortcodes = require('remark-shortcodes');

var ast = {
  "type": "root",
  "children": [
    {
      "type": "paragraph",
      "children": [{ "type": "text", "value": "Example paragraph" }]
    },
    {
      "type": "shortcode",
      "identifier": "MailchimpForm",
      "attributes": { "id": "chfk2" }
    }
  ]
};

var tree = unified()
  .use(parse)
  // Plugin inserted below, with custom options for start/end blocks.
  .use(shortcodes, {startBlock: "{{>", endBlock: "<}}"})
  .stringify(ast);

console.log(tree);

Running node example2 yields:

Example paragraph\n\n{{> MailchimpForm id="chfk2" <}}

Say example3.js looks as follows:

var unified = require('unified');
var parse = require('remark-parse');
var shortcodes = require('remark-shortcodes');

var markdown = 'Example paragraph {{> MailchimpForm id="chfk2" <}}'

var tree = unified()
  .use(parse)
  // Plugin inserted below, with custom options for start/end blocks.
  .use(shortcodes, {startBlock: "{{>", endBlock: "<}}", inlineMode: true})
  // Turn off position output for legibility below.
  .data('settings', {position: false})
  .parse(markdown);

console.dir(tree, {depth: null});

Running node example3 yields:

{
  "type": "root",
  "children": [
    {
      "type": "paragraph",
      "children": [
        {
          "type": "text",
          "value": "Example paragraph "
        },
        {
          "type": "shortcode",
          "identifier": "MailchimpForm",
          "attributes": { "id": "chfk2" }
        }
      ]
    }
  ]
}

API

remark.use(shortcodes, {options})

Where options support the keys:

• startBlock: the start block to look for. Default: [[.
• endBlock: the end block to look for. Default: ]].
• inlineMode: shortcodes will be parsed inline rather than in block mode. Default: false.

NB: Be careful when using custom start/end blocks, your choices may clash with other markdown syntax and/or other remark plugins.

Testing

To run the tests, run:

npm run test-code

To run build, tests & coverage, run:

npm run test

Releasing

Prepare the commits:

• Bump all version numbers.
• Tag the commit: git tag -a v0.1.x -m v0.1.x
• Push tag to Github: git push --tags

Publish to npm:

• Ensure tag is checked-out: git checkout tags/v0.1.x
• Login to NPM via the CLI: npm login
• Publish the package: npm publish

License

MIT © Darian Moody

With thanks to woorm et. al for remark.