Return list of files in directory from Jekyll plugin?

Question

I can't figure out how to create a filter or tag in a jekyll plugin, so that I can return a directory and loop over its contents. I found these:

http://pastebin.com/LRfMVN5Y

http://snippets.dzone.com/posts/show/302

So far I have:

module Jekyll
  class FilesTag < Liquid::Tag

    def initialize(tag_name, text, tokens)
      super
      @text = text
    end

    def render(context)
        #"#{@text} #{Time.now}"
        Dir.glob("images/*").each { |i| "#{i}" }
        #Dir.glob("images/*")
        #Hash[*Dir.glob("images/*").collect { |v| [v, v*2] }.flatten]
    end
  end
end

Liquid::Template.register_tag('files', Jekyll::FilesTag)

I can successfully return the list of images as a string and print it with:

{% files test_string %}

But for the life of me, I can't loop over the array, no matter how I return the array/hash from Dir.glob. I just want to be able to do:

{% for image in files %}
    image
{% endfor %}

I'm going to need to be able to return arrays of things constantly for the various collections I'll be using on the site. I just need a barebones plugin to build upon.

Thanks!

---

UPDATE: I partially solved it. This method works but requires using endloop_directory instead of endfor, which seems a bit ugly to me. Also, the filter is unable to take a parameter like *.{jpg,png} because there is no way to escape the {} in the html. Open to suggestions on how to pass a regex string in an attribute...

#usage:
#{% loop_directory directory:images iterator:image filter:*.jpg sort:descending %}
#   <img src="{{ image }}" />
#{% endloop_directory %}
module Jekyll
    class LoopDirectoryTag < Liquid::Block

        include Liquid::StandardFilters
        Syntax = /(#{Liquid::QuotedFragment}+)?/

        def initialize(tag_name, markup, tokens)
            @attributes = {}

            @attributes['directory'] = '';
            @attributes['iterator'] = 'item';
            @attributes['filter'] = 'item';
            @attributes['sort'] = 'ascending';

            # Parse parameters
            if markup =~ Syntax
                markup.scan(Liquid::TagAttributes) do |key, value|
                    @attributes[key] = value
                end
            else
                raise SyntaxError.new("Bad options given to 'loop_directory' plugin.")
            end

            #if @attributes['directory'].nil?
            #   raise SyntaxError.new("You did not specify a directory for loop_directory.")
            #end

            super
        end

        def render(context)
            context.registers[:loop_directory] ||= Hash.new(0)

            images = Dir.glob(File.join(@attributes['directory'], @attributes['filter']))

            if @attributes['sort'].casecmp( "descending" ) == 0
                # Find files and sort them reverse-lexically. This means
                # that files whose names begin with YYYYMMDD are sorted newest first.
                images.sort! {|x,y| y <=> x }
            else
                # sort normally in ascending order
                images.sort!
            end

            length = images.length
            result = []

            context.stack do
                images.each_with_index do |item, index|
                    context[@attributes['iterator']] = item
                    context['forloop'] =
                    {
                        'name' => @attributes['iterator'],
                        'length' => length,
                        'index' => index + 1,
                        'index0' => index,
                        'rindex' => length - index,
                        'rindex0' => length - index - 1,
                        'first' => (index == 0),
                        'last' => (index == length - 1) 
                    }

                    result << render_all(@nodelist, context)
                end
            end

            result
        end
    end
end

Liquid::Template.register_tag('loop_directory', Jekyll::LoopDirectoryTag)

Answer 1

I found a plugin here: How to list files in a directory with Liquid? that might do the trick:

Jekyll::DirectoryTag This tag lets you iterate over files at a particular path. The directory tag yields a file object and a forloop object. If files conform to the standard Jekyll format, YYYY-MM-DD-file-title, then those attributes will be populated on that file object.

https://github.com/sillylogger/jekyll-directory