Jekyll Image Data

Image data for Jekyll posts and pages. Crawls generated HTML files in search of image data ("src" and "alt" attributes) and makes it available as a post/page metadata attribute.

Installation

Add this line to your application's Gemfile:

gem "jekyll-image-data"

And then execute:

$ bundle

Or install it yourself as:

$ gem install jekyll-image-data

Usage

Define your images using Markdown format, plain HTML or by including a .liquid file:

![Alt text](/image-url)

or

![Alt text][ref]
[ref]: /image-url

<img src="http://placehold.it/800x600" alt="Image">

{% include image.liquid src="http://placehold.it/800x600" alt="Image" %}

Note that the included file must be named image.liquid or image.html and must accept two parameters: src and alt.

This plugin gets executed in the :posts, :pre_render and :pages, :post_init hooks. After execution, post.data["images"] or page.data["images"] will hold alt and src data for all images inside post/page:

post.data["images"] = [
  { "alt" => "Alt text", "url" => "/media/images/800x600.png" },
  { "alt" => "Alt text", "url" => "/media/images/800x600.jpg" },
  { "alt" => "Alt text", "url" => "/media/images/800x600.gif" }
]

{% for image in page.images %}
  <img alt="{{ image.alt }}" src="{{ image.url }}" >
{% endfor %}

Excluding images

If you don't want data from some images to be included in the post.data["images"] or page.data["images"] variables, you can add the image URL to the exclude setting in the _config.yml file:

image_data:
  exclude: "/media/images/800x600.png"

Remember this setting is a regular expression. You can put the complete URL of the images or just part of it. In the above example, data from any image that contains the string /media/images/800x600.png in the src attribute won't be added to the data variable for any post or page.

Development

After checking out the repo, run script/setup to install dependencies. Then, run rake spec to run the tests. You can also run script/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/rukbotto/jekyll-image-data.

License

The gem is available as open source under the terms of the MIT License.