bespoke-markdownit

Allows you to use (GitHub flavored) Markdown to author your bespoke.js presentation. There are 4 ways to use this plugin and they are described on the demo page.

bespoke-markdownit renders Markdown in HTML using the awesome markdown-it parser.

Download

Download the production version or the development version, or use a package manager.

Usage

There are 3 steps to using this plugin.

Including and initializing the plugin
Including a stylesheet for code highlighting
Authoring the presentation using Markdown

1. Including and initializing the plugin

This plugin is shipped in a UMD format, meaning that it is available as a CommonJS/AMD module or browser global.

For example, when using CommonJS modules:

const bespoke = require('bespoke'),
  markdown = require('bespoke-markdownit');

bespoke.from('#presentation', [
  markdown()
]);

If using browser globals:

bespoke.from('#presentation', [
  bespoke.plugins.markdownIt()
]);

Plugin Options

The plugin builder accepts up to 2 parameters for configuration. The first allows the definition of metadata for each slide. That data can be used by callbacks provided to the plugin builder function. The second parameter allows passing plugins to the markdown-it parser. There are various markdown-it plugins, such as one to extend the Markdown syntax to allow <abbr></abbr> (markdown-it-abbr).

Let us see how to use both parameters.

1st parameter: Slide metadata

The first parameter, if defined, is a object whose keys are names of functions and values are callbacks to be invoked when certain Markdown slides are parsed.

For example, if we want to add some class to a specific Markdown slide, we can add metadata to that slide with the name of the class it should have and provide a function to the plugin builder that just adds a class to the slide owner of the metadata. The Markdown file would look like:

# First slide
---
<!--
{
  "addClassToSlide": "2-columns-slide-layout"
}
-->
# Second slide

![](image-left-side.png)
![](image-right-side.png)
---
# Third slide

Then, we need to provide a property called addClassToSlide which contains a callback that effectively adds a class to the slide:

bespoke.from('#presentation',
  markdown({
    // slideEl is the HTMLElement of the slide (it is always provided
    //   as the first argument)
    // className is the value defined as the metadata. It could be any
    //   JSON value
    addClassToSlide: function(slideEl, className) {
      slideEl.classList.push(className);
    },
    // another metadata callback function that can be called
    logThisMessage: function(slideEl, message) {
      console.log(message);
    }
  })
);

The example would result in the following HTML:

<article id="presentation">
  <section>
    <h1>First Slide</h1>
  </section>
  <section class="2-columns-slide-layout">
    <h1>Second Slide</h1>
    <img src="image-left-side.png" alt="">
    <img src="image-right-side.png" alt="">
  </section>
  <section>
    <h1>Third Slide</h1>
  </section>
</article>

The metadata must be defined as an HTML comment as the first thing in a slide (i.e., right after the ---, on a new line). Besides, its content must be a valid JSON string, otherwise the comment will just be ignored by the bespoke-markdownit plugin (in fact, we use JSON.parse() on the comment node value).

It is possible to call various callback functions from the metadata by providing multiple keys, as in the following example.

<!--
{
  "addClassToSlide": "pinky",
  "logThisMessage": "yayyyyy"
}
-->
# First Slide

Additionally, if a value is passed as an array or an object, the callback function will receive it proper, such as illustrated.

<!--
{
  "injectStylesheets": ["main.css", "ribbon.css"]
}
-->

And on the plugin builder function:

bespoke.from('#presentation',
  markdown({
    injectStylesheets: function(slideEl, fileNames) {
      fileNames = Array.isArray(fileName) ? fileNames : [fileNames];
      fileNames.forEach(name => {
        const sheet = document.createElement('link');
        sheet.setAttribute('rel', 'stylesheet');
        sheet.setAttribute('href', name);
        slideEl.appendChild(sheet);        
      });
    }
  })
);

2nd parameter: markdown-it plugins

The second parameter allows passing markdown-it plugins to the markdown-it parser. If provided, it should be an array of plugin builder functions, such as in the following example.

// ...
const abbrPlugin = require('markdown-it-abbr');
const decoratePlugin = require('markdown-it-decorate');
bespoke.from('#presentation',
  markdown(
    // the first argument must be supplied, even if not using metadata
    {},
    // an array of plugin builder functions
    [abbrPlugin, decoratePlugin]
  )
);

The order in which they are passed to the bespoke-markdownit builder is the same that it passes along to markdown-it.

2. Stylesheet for code highlighting

If you want code highlighting, you also need to include a stylesheet from highlight.js, which is the package used by this plugin. One option to include it is via the dependencies of this plugin, as highlight.js is a dependency of bespoke-markdownit.

In that case, you can include it by:

<link rel="stylesheet" type="text/css" href="node_modules/highlight.js/styles/THEME_NAME.css" />

You can choose any theme from highlight.js and put it instead of THEME_NAME. Some themes are:

default.css
monokai-sublime.css
sublime.css
github.css

3. Authoring presentation using Markdown

Just by including the plugin code and initializing bespoke with it will allow writing the content of the slides in Markdown. You can use a markup similar to the following:

<article>
  <section>
# Title
This is **markdown content**.
  </section>
</article>

You can also write Markdown content in external files. You can do it for the whole presentation or for specific slides. To mark a slide to be rendered using Markdown, you need to add the data-markdown="path-to-file.md" attribute to the presentation HTML element, like so:

<article data-markdown="presentation.md"></article>

Or, you can add it to specific slides only:

<article>
  <section data-markdown="slide-1.md"></section>
  <section>
    <p>A slide authored in HTML</p>
  </section>
  <section data-markdown="slide-3.md"></section>
</article>

You can split the .md file in multiple slides by using "---" to separate them. For instance, presentation.md:

This is the first slide
---
Second slide
---
And third!

Additionally, you can mix slides authored in HTML and in Markdown. To mark a slide to have its contents rendered as Markdown, we also use the data-markdown attribute, but without a value (or with an empty value, i.e., data-markdown=""). Check the example:

<article>
  <section data-markdown>
    # Title 1
    This is a slide authored in Markdown.
  </section>
  <section data-markdown="">
    # Title 2
    This is also a slide authored in Markdown.
  </section>
  <section>
    <h1>Title 3</h1>
    <p>This is a slide authored in HTML.</p>
  </section>
</article>

Package managers

npm

$ npm install bespoke-markdownit

History and Motivation

bespoke-markdownit was forked from bespoke-markdown and is also inspired by bespoke-meta-markdown.

bespoke-markdown uses marked as its parser, which bespoke-markdownit improves by using markdown-it. The latter is not as fast as marked, but it was designed to be extensible through plugins from the beggining and, as such, is much more flexible.

bespoke-meta-markdown is, in turn, a fork of bespoke-markdown that allows the definition of slide metadata inside HTML comments but in the YAML format. For so, it has a larger signature than this plugin as it has to include a YAML parser.

Credits

This plugin was built with generator-bespokeplugin.

License

MIT License