zola/docs/content/documentation/content/shortcodes.md
2018-10-13 11:15:19 +02:00

5.8 KiB

+++ title = "Shortcodes" weight = 40 +++

While Markdown is good at writing, it isn't great when you need write inline HTML to add some styling for example.

To solve this, Gutenberg borrows the concept of shortcodes from WordPress. In our case, the shortcode corresponds to a template that is defined in the templates/shortcodes directory or a built-in one that can be used in a Markdown file. If you want to use something similar to shortcodes in your templates, try Tera macros.

Writing a shortcode

Let's write a shortcode to embed YouTube videos as an example. In a file called youtube.html in the templates/shortcodes directory, paste the following:

<div {% if class %}class="{{class}}"{% endif %}>
    <iframe
        src="https://www.youtube.com/embed/{{id}}{% if autoplay %}?autoplay=1{% endif %}"
        webkitallowfullscreen
        mozallowfullscreen
        allowfullscreen>
    </iframe>
</div>

This template is very straightforward: an iframe pointing to the YouTube embed URL wrapped in a <div>. In terms of input, it expects at least one variable: id. Since the other variables are in a if statement, we can assume they are optional.

That's it, Gutenberg will now recognise this template as a shortcode named youtube (the filename minus the .html extension).

The markdown renderer will wrap an inline HTML node like <a> or <span> into a paragraph. If you want to disable that, simply wrap your shortcode in a div.

Using shortcodes

There are two kinds of shortcodes:

  • ones that do not take a body like the YouTube example above
  • ones that do, a quote for example

In both cases, their arguments must be named and they will all be passed to the template.

Lastly, a shortcode name (and thus the corresponding .html file) as well as the arguments name can only contain numbers, letters and underscores, or in Regex terms the following: [0-9A-Za-z_]. While theoretically an argument name could be a number, it will not be possible to use it in the template in that case.

Argument values can be of 5 types:

  • string: surrounded by double quotes, single quotes or backticks
  • bool: true or false
  • float: a number with a . in it
  • integer: a number without a . in it
  • array: an array of any kind of values, except arrays

Malformed values will be silently ignored.

Both type of shortcodes will also get either a page or section variable depending on where they were used and a config one. Those values will overwrite any arguments passed to a shortcode so shortcodes should not use arguments called like one of these.

Shortcodes without body

Simply call the shortcode as if it was a Tera function in a variable block. All the examples below are valid calls of the YouTube shortcode.

Here is a YouTube video:

{{/* youtube(id="dQw4w9WgXcQ") */}}

{{/* youtube(id="dQw4w9WgXcQ", autoplay=true) */}}

An inline {{/* youtube(id="dQw4w9WgXcQ", autoplay=true, class="youtube") */}} shortcode

Note that if you want to have some content that looks like a shortcode but not have Gutenberg try to render it, you will need to escape it by using {{/* and */}} instead of {{ and }}.

Shortcodes with body

For example, let's imagine we have the following shortcode quote.html template:

<blockquote>
    {{ body }} <br>
    -- {{ author}}
</blockquote>

We could use it in our markup file like so:

As someone said:

{%/* quote(author="Vincent") */%}
A quote
{%/* end */%}

The body of the shortcode will be automatically passed down to the rendering context as the body variable and needs to be in a newline.

If you want to have some content that looks like a shortcode but not have Gutenberg try to render it, you will need to escape it by using {%/* and */%} instead of {% and %}. You won't need to escape anything else until the closing tag.

Built-in shortcodes

Gutenberg comes with a few built-in shortcodes. If you want to override a default shortcode template, simply place a {shortcode_name}.html file in the templates/shortcodes directory and Gutenberg will use that instead.

YouTube

Embed a responsive player for a YouTube video.

The arguments are:

  • id: the video id (mandatory)
  • class: a class to add the div surrounding the iframe
  • autoplay: whether to autoplay the video on load

Usage example:

{{/* youtube(id="dQw4w9WgXcQ") */}}

{{/* youtube(id="dQw4w9WgXcQ", autoplay=true) */}}

{{/* youtube(id="dQw4w9WgXcQ", autoplay=true, class="youtube") */}}

Result example:

{{ youtube(id="dQw4w9WgXcQ") }}

Vimeo

Embed a player for a Vimeo video.

The arguments are:

  • id: the video id (mandatory)
  • class: a class to add the div surrounding the iframe

Usage example:

{{/* vimeo(id="124313553") */}}

{{/* vimeo(id="124313553", class="vimeo") */}}

Result example:

{{ vimeo(id="124313553") }}

Streamable

Embed a player for a Streamable video.

The arguments are:

  • id: the video id (mandatory)
  • class: a class to add the div surrounding the iframe

Usage example:

{{/* streamable(id="92ok4") */}}

{{/* streamable(id="92ok4", class="streamble") */}}

Result example:

{{ streamable(id="92ok4") }}

Gist

Embed a Github gist.

The arguments are:

  • url: the url to the gist (mandatory)
  • file: by default, the shortcode will pull every file from the URL unless a specific filename is requested
  • class: a class to add the div surrounding the iframe

Usage example:

{{/* gist(url="https://gist.github.com/Keats/e5fb6aad409f28721c0ba14161644c57") */}}

{{/* gist(url="https://gist.github.com/Keats/e5fb6aad409f28721c0ba14161644c57", class="gist") */}}

Result example:

{{ gist(url="https://gist.github.com/Keats/e5fb6aad409f28721c0ba14161644c57") }}