Eleventy Plugin Metagen

eleventy-plugin-metagen is a <meta> tag generator for sites built with Eleventy. Generate meta tags for Open Graph and Twitter along with some other useful tags. All of the tags necessary for a baseline social share functionality are included with this plugin along with some additional tags for more custom use cases.

Installation

In your Eleventy project, install the plugin from npm:

npm install eleventy-plugin-metagen

Then add it to your Eleventy Config file:

const metagen = require('eleventy-plugin-metagen');

module.exports = (eleventyConfig) => {
eleventyConfig.addPlugin(metagen);
};

What does it do?

The plugin turns 11ty shortcodes like this:

{% metagen
title="Eleventy Plugin Meta Generator",
desc="An eleventy shortcode for generating meta tags.",
url="https://tannerdolby.com",
img="https://tannerdolby.com/images/arch-spiral-large.jpg",
img_alt="Archimedean Spiral",
twitter_card_type="summary_large_image",
twitter_handle="tannerdolby",
name="Tanner Dolby",
comments=true
%}

into <meta> tags and other document metadata like this:

<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Eleventy Plugin Meta Generator</title>
<meta name="author" content="Tanner Dolby">
<meta name="description" content="An eleventy shortcode for generating meta tags.">
<meta name="generator" content="eleventy">
<!-- Open Graph -->
<meta property="og:type" content="website">
<meta property="og:locale" content="en_US">
<meta property="og:title" content="Eleventy Plugin Meta Generator">
<meta property="og:description" content="An eleventy shortcode for generating meta tags.">
<meta property="og:url" content="https://tannerdolby.com">
<meta property="og:image" content="https://tannerdolby.com/images/arch-spiral-large.jpg">
<meta property="og:image:alt" content="Archimedean Spiral">
<!-- Twitter -->
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:site" content="@tannerdolby">
<meta name="twitter:creator" content="@tannerdolby">
<meta name="twitter:url" content="https://tannerdolby.com">
<meta name="twitter:title" content="Eleventy Plugin Meta Generator">
<meta name="twitter:description" content="An eleventy shortcode for generating meta tags.">
<meta name="twitter:image" content="https://tannerdolby.com/images/arch-spiral-large.jpg">
<meta name="twitter:image:alt" content="Archimedean Spiral">
<link rel="canonical" href="https://tannerdolby.com">

Custom Usage

For a baseline social share functionality, providing all of the comma separated arguments to metagen shown in the example usage above is recommended. If you want to add more meta tags that are not listed in the example, see parameters for supported tags. You might only need a few <meta> tags instead of the whole set, simply provide the arguments you need and the ones not included won't generate <meta> tags.

Besides the default generated <meta> tags, only the arguments you provide data for will be generated as <meta> tags. This allows you to include some of your own tags alongside metagen if you need. Template variables can be used in the Nunjucks and Liquid shortcode arguments without the curly braces or quotes like title=page.url (Nunjucks) or title (Liquid). More on template variable usage below

Shortcode Default Tags

If atleast one parameter is provided to metagen:

{% metagen 
comments=true
%}

the default <meta> tags aside from the main Open Graph and Twitter card data are:

<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Open Graph -->
<meta property="og:type" content="website">
<meta property="og:locale" content="en_US">
<!-- Twitter -->
<meta name="twitter:card" content="summary">

The title parameter provides data for <title>. If title is not defined within metagen, the <title> element will not be generated with the above default tags. The same rules apply for name and desc. All other arguments if omitted, will not have meta tags generated.

Using {% metagen %} without any arguments will throw Error: No data was added into the meta generator and return an empty string.

Shorthand Nunjucks Usage

To use the shortcode as a one-liner. You can define an object in frontmatter, global data or another data source with the required key/value pairs and supply the shortcode with a single object parameter.

---
data:
title: Eleventy Plugin Add Meta Tags
desc: An eleventy shortcode for generating meta tags.
url: https://tannerdolby.com
img: https://tannerdolby.com/images/arch-spiral-large.jpg
img_alt: Archimedean Spiral
twitter_card_type: summary_large_image
twitter_handle: tannerdolby
name: Tanner Dolby
---
<head>
{% metagen data %}
</head>

Use Your Template Data

To make your metadata dynamic, you can use template data as arguments to the shortcode, without quotes or braces:

---
title: Some title
desc: Some description
metadata:
title: Some other title
desc: Some other description
url: https://tannerdolby.com
image: https://tannerdolby.com/images/arch-spiral-large.jpg
alt: Archimedean spiral
type: summary_large_image
twitter: tannerdolby
name: Tanner Dolby
---
{% metagen
title=title or metadata.title,
desc=desc or metadata.desc,
url=url + page.url,
img=image,
img_alt=alt,
twitter_card_type=type,
twitter_handle=twitter,
name=name
%}

As a general rule, don't forget your in a templating engine context. Use your variables in the shortcode as you would inside {% var %} tags or {{ var }} without the curly braces like title=var.

Liquid Usage

If you would like to use Liquid (which is the default templating engine in Eleventy). Then utilize the following syntax, to turn shortcodes like this:

---
data:
title: Eleventy Plugin Add Meta Tags
desc: An eleventy shortcode for generating meta tags.
url: https://tannerdolby.com
img: https://tannerdolby.com/images/arch-spiral-large.jpg
img_alt: Archimedean Spiral
twitter_card_type: summary_large_image
twitter_handle: tannerdolby
name: Tanner Dolby
---
<head>
{% metagen data %}
</head>

The Liquid usage is a bit different as the shortcode expects a single parameter representing an object with key/value pairs. You can define the object in frontmatter like shown above or within global data files.

Shortcode Parameters

A list containing all of the parameters this plugin accepts. If you can't find a parameter that suits your all of your needs, feel free to open an issue so we can get the parameter and/or corresponding meta tag added to the plugin.

twitter_card_type

The content for twitter:card. default: 'summary'

name

The content for <meta name="author">.

title

The content for <title>, <meta name="title">, twitter:title and og:title. If og_title and twitter_title are defined they will override the fields.

desc

The content for twitter:description, og:description and <meta name="description"> if og_desc or twitter_desc isn't defined.

url

The content for twitter:url and og:url.

img

The content for twitter:image and og:image.

img_alt

The content for twitter:image:alt and og:image:alt.

img_width

The content for og:image:width.

img_height

The content for og:image:height.

twitter_handle

The content for twitter:site or twitter:creator if the card type is summary_large_image.

creator_handle

The content for twitter:creator. This tag is used if the twitter_card_type is summary_large_image.

site_name

The content for og:site_name.

attr_name

Define attribute name for the Twitter set of meta tags. Options are 'property' or the default 'name'. default: name

locale

The locale these tags are marked up in. default: 'en_US'

comments

Display default comments for the Open Graph and Twitter tags. default: false

generator

The content for <meta name="generator">. The value must be a free-form string that identifies one of the software packages used to generate the document. This value must not be used on pages whose markup is not generated by software, e.g. pages whose markup was written by a user in a text editor.

og_type

The content for og:type. options: "website" (default), "proudct", "article"

og_title

The content for og:title. default: title

twitter_title

The content for twitter:title. default: title

og_desc

The content for og:description. default: desc

twitter_desc

The content for twitter:description. default: desc

og_comment

Display a custom comment for the Open Graph set of tags. requires: comments=true

twitter_comment

Display a custom comment for the Twitter set of tags. requires: comments=true