Bootstrap4Markdown

A Python-Markdown extension which provides a simple syntax for including Bootstrap objects within a Markdown document.

Installation

To install the extension, run the following command:

pip install bootstrap4markdown

Usage

To use the extension, include its name in the list of extensions passed to Python-Markdown.

import markdown
markdown.markdown(src, extensions=['bs4md'])

Note that this extension only generates the requisite HTML for the supported Bootstrap components. The user is responsible for providing the necessary CSS and Javascript for the Bootstrap theme being used. The generated HTML assumes Bootstrap version 5.3.

Syntax

Bootstrap4Markdown is built on top of the Blocks extension. Therefore, all blocks use the same basic form.

/// name-of-block | argument
    option: value

content
///

Therefore, each supported Bootstrap object maps to a specific block name as defined below.

Alerts

Bootstrap based alerts can be defined using blocks named alert.

/// alert
This is an alert.
///

A title (or heading) can be defined using the block's argument.

/// alert | Title
This alert has a title.
///

The color of the alert can be altered using the type option. For example, setting type: warning will result in the alert-warning style being used from your Bootstrap theme.

/// alert | Warning
    type: warning

This is a **warning** alert with a title.
///

Valid types are the string names of any of Bootstraps contextual classes: primary, secondary, success, danger, warning, info, light, and dark.

Notice that the body content body of the alert contains standard Markdown content. By default the content will be parsed as a single block (paragraph) and only inline level Markdown parsing will be applied to the content. However, if the markdown option is set to block, then block-level parsing will be applied to the content as well.

/// alert
    markdown: block

This alert contains two paragraphs of Markdown text.

This is the second paragraph.
///

An alert will include a dismiss button if dismissable is set to true.

/// alert
    dismissable: true

You can dismiss me!
///

Finally, any additional HTML attributes can be defined for the outer element of the alert using the attrs option.

/// alert
    attrs:
        id: mycustomid
        class: p-5

Custom padding is set for this alert using on of Bootstraps'
[spacing](https://getbootstrap.com/docs/5.3/utilities/spacing/)
classes. (`p-5`).
///

Options

Carousel

A Bootstrap based carousel (or slideshow) can be defined using two types of blocks: the outer carousel block and a separate slide block for each component of the slideshow.

//// carousel

/// slide | image1.jpg
    alt: Slide one.
///

/// slide | image2.jpg
    alt: Slide two.
///

////

Note that all slide blocks must be nested in a carousel block. Also, be sure to use a different number of slashes for the parent carousel block than the child slide blocks.

Carousel Block

The outer carousel block is used to define global options which apply to the entire slideshow.

//// carousel
    attrs: {id: 'mycustomid'}
    controls: false
    indicators: true
    fade: true
    autoplay: carousel
    touch: false

...
////

Note that Boostrap requires each carousel to have a unique id defined for it to work correctly. If one is not defined in the attrs, then a random UUID string will be generated and assigned as the id of the carousel.

Slide Block

Nested within the carousel block, each slide is defined by a slide block. Slides may take one of a few forms. The simplest form is an image.

///
slide | path/to/image.jpg
    alt: Some alt text for the image.
///

Note that the path to the image is defined in the argument and the alt text in the alt option.

Image slides can also define a caption, which is text that overlays the image. The caption is defined in the body of the image.

///
slide | path/to/image.jpg
    alt: Some alt text for the image.

# Caption Title

Caption Body.
///

However, if no argument is provided, then the body content is used as the body of the slide. In both cases, Markdown processing is applied to the body content.

/// slide
    attrs: {class: 'text-center pt-5 bg-primary-subtle text-primary-emphasis min-vh-100'}

# HTML Slide

Slide Body
///

Note that various Bootstrap classes were set on the above slide. As Bootstrap's documentation explains:

Carousels don’t automatically normalize slide dimensions. As such, you may need to use additional utilities or custom styles to appropriately size content.

Of course, raw HTML can be used as well. For example, the following slide includes a slide comprised of an SVG element.

/// slide
    markdown: inline

<svg class="d-block w-100" width="800" height="400" xmlns="http://www.w3.org/2000/svg" role="img" aria-label="Placeholder" preserveAspectRatio="xMidYMid slice" focusable="false">
<title>Placeholder</title>
<rect width="100%" height="100%" fill="#777"></rect>
<text x="50%" y="50%" fill="#555" dy=".3em">SVG Slide</text>
</svg>
///

In the above slide, the markdown option was set to inline so that the svg would not be wrapped in a Markdown paragraph. However, when using block-level raw HTML, you will want to indent the content one level (4 spaces) and set the markdown option to raw to ensure that Markdown parsing does not muck up your custom crafted HTML.

/// slide
    markdown: raw

    <h4>Title</h4>
    <p>Custom Body Content</p>
///

Note that if more that one slide is set to active: true, then only the first of all "active" slides is actually set to active. If no slides are explicitly set to be active, then the first slide in the carousel is set to be active by default.

License

The Bootstrap4Markdown Extension to Python-Markdown is licensed under the MIT License as defined in LICENSE.

Change Log

Version 0.1 (2023-03-07)

The initial release. Includes support for Alerts and Carousels.