Tag cloud

.themes/classic/source/_includes/asides/tag_cloud.html

@@ -0,0 +1,4 @@
+<section class="tag-cloud">
+  <h1>Tags</h1>
+  {% tag_cloud %}
+</section>

.themes/classic/source/_layouts/tag_index.html

@@ -0,0 +1,17 @@
+---
+layout: page
+footer: false
+---
+
+<div id="blog-archives" class="tag">
+{% for post in site.tags[page.tag] %}
+{% capture this_year %}{{ post.date | date: "%Y" }}{% endcapture %}
+{% unless year == this_year %}
+  {% assign year = this_year %}
+  <h2>{{ year }}</h2>
+{% endunless %}
+<article>
+  {% include archive_post.html %}
+</article>
+{% endfor %}
+</div>

_config.yml

@@ -32,6 +32,7 @@ destination: public
 plugins: plugins
 code_dir: downloads/code
 category_dir: blog/categories
+tag_dir: blog/tags
 markdown: rdiscount
 pygments: false # default python pygments have been replaced by pygments.rb
 
@@ -44,7 +45,7 @@ titlecase: true       # Converts page and post titles to tilecase
 
 # list each of the sidebar modules you want to include, in the order you want them to appear.
 # To add custom asides, create files in /source/_includes/custom/asides/ and add them to the list like 'custom/asides/custom_aside_name.html'
-default_asides: [asides/recent_posts.html, asides/github.html, asides/twitter.html, asides/delicious.html, asides/pinboard.html, asides/googleplus.html]
+default_asides: [asides/recent_posts.html, asides/github.html, asides/twitter.html, asides/delicious.html, asides/pinboard.html, asides/googleplus.html, asides/tag_cloud.html]
 
 # Each layout uses the default asides, but they can have their own asides instead. Simply uncomment the lines below
 # and add an array with the asides you want to use.

plugins/tag_cloud.rb

@@ -0,0 +1,48 @@
+module Jekyll
+  class TagCloud < Liquid::Tag
+
+    CLOUD_MAX_RANKS = 5;
+    CLOUD_SIZE = 100;
+
+    def render(context)
+      s = StringIO.new
+      begin
+        tags = context['site']['tags']
+        unless tags.nil?
+          sorted = tags.sort {|a, b| b[1].length <=> a[1].length}
+          factor = 1
+          max_count = sorted[0][1].length
+          min_count = sorted[-1][1].length
+
+          if max_count == min_count
+            min_count -= CLOUD_MAX_RANKS
+          else
+            factor = (CLOUD_MAX_RANKS - 1) / Math.log(max_count - min_count + 1)
+          end
+
+          if sorted.length < CLOUD_MAX_RANKS
+            factor *= sorted.length / CLOUD_MAX_RANKS.to_f
+          end
+
+          for index in (0..CLOUD_SIZE).to_a.shuffle do
+            if sorted[index].nil?
+              next
+            end
+
+            dir = context['site']['tag_dir'] || 'tag'
+            rank = CLOUD_MAX_RANKS - (Math.log(sorted[index][1].length - min_count + 1) * factor).to_i
+            s << "<span class='rank-#{rank}'>"
+            s << "<a href='/#{dir}/#{sorted[index][0].gsub(/_|\W/, '-')}'>#{sorted[index][0]}</a>"
+            s << "</span> "
+          end
+        end
+      rescue => boom
+        # Nothing, I think
+        p boom
+      end
+      s.string
+    end
+  end
+end
+
+Liquid::Template.register_tag('tag_cloud', Jekyll::TagCloud)

plugins/tag_generator.rb

@@ -0,0 +1,136 @@
+# Jekyll tag page generator.
+# http://recursive-design.com/projects/jekyll-plugins/
+#
+# Version: 0.1.4 (201101061053)
+#
+# Copyright (c) 2010 Dave Perrett, http://recursive-design.com/
+# Licensed under the MIT license (http://www.opensource.org/licenses/mit-license.php)
+#
+# A generator that creates tag pages for jekyll sites.
+#
+# Included filters :
+# - tag_links:      Outputs the list of tags as comma-separated <a> links.
+# - date_to_html_string: Outputs the post.date as formatted html, with hooks for CSS styling.
+#
+# Available _config.yml settings :
+# - tag_dir:          The subfolder to build tag pages in (default is 'tags').
+# - tag_title_prefix: The string used before the tag name in the page title (default is
+#                          'Tag: ').
+module Jekyll
+
+
+  # The TagIndex class creates a single tag page for the specified tag.
+  class TagIndex < Page
+
+    # Initializes a new TagIndex.
+    #
+    #  +base+         is the String path to the <source>.
+    #  +tag_dir+ is the String path between <source> and the tag folder.
+    #  +tag+     is the tag currently being processed.
+    def initialize(site, base, tag_dir, tag)
+      @site = site
+      @base = base
+      @dir  = tag_dir
+      @name = 'index.html'
+      self.process(@name)
+      # Read the YAML data from the layout page.
+      self.read_yaml(File.join(base, '_layouts'), 'tag_index.html')
+      self.data['tag']    = tag
+      # Set the title for this page.
+      title_prefix             = site.config['tag_title_prefix'] || 'Tag: '
+      self.data['title']       = "#{title_prefix}#{tag}"
+      # Set the meta-description for this page.
+      meta_description_prefix  = site.config['tag_meta_description_prefix'] || 'Tag: '
+      self.data['description'] = "#{meta_description_prefix}#{tag}"
+    end
+
+  end
+
+
+  # The Site class is a built-in Jekyll class with access to global site config information.
+  class Site
+
+    # Creates an instance of TagIndex for each tag page, renders it, and
+    # writes the output to a file.
+    #
+    #  +tag_dir+ is the String path to the tag folder.
+    #  +tag+     is the tag currently being processed.
+    def write_tag_index(tag_dir, tag)
+      index = TagIndex.new(self, self.source, tag_dir, tag)
+      index.render(self.layouts, site_payload)
+      index.write(self.dest)
+      # Record the fact that this page has been added, otherwise Site::cleanup will remove it.
+      self.pages << index
+    end
+
+    # Loops through the list of tag pages and processes each one.
+    def write_tag_indexes
+      if self.layouts.key? 'tag_index'
+        dir = self.config['tag_dir'] || 'tag'
+        self.tags.keys.each do |tag|
+          self.write_tag_index(File.join(dir, tag.gsub(/_|\W/, '-')), tag)
+        end
+
+      # Throw an exception if the layout couldn't be found.
+      else
+        throw "No 'tag_index' layout found."
+      end
+    end
+
+  end
+
+
+  # Jekyll hook - the generate method is called by jekyll, and generates all of the tag pages.
+  class GenerateTags < Generator
+    safe true
+    priority :low
+
+    def generate(site)
+      site.write_tag_indexes
+    end
+
+  end
+
+
+  # Adds some extra filters used during the tag creation process.
+  module Filters
+
+    # Outputs a list of tags as comma-separated <a> links. This is used
+    # to output the tag list for each post on a tag page.
+    #
+    #  +tags+ is the list of tags to format.
+    #
+    # Returns string
+    #
+    def tag_links(tags)
+      dir = @context.registers[:site].config['tag_dir']
+      tags = tags.sort!.map do |item|
+        "<a class='tag' href='/#{dir}/#{item.gsub(/_|\W/, '-')}/'>#{item}</a>"
+      end
+
+      case tags.length
+      when 0
+        ""
+      when 1
+        tags[0].to_s
+      else
+        "#{tags[0...-1].join(', ')}, #{tags[-1]}"
+      end
+    end
+
+    # Outputs the post.date as formatted html, with hooks for CSS styling.
+    #
+    #  +date+ is the date object to format as HTML.
+    #
+    # Returns string
+    def date_to_html_string(date)
+      result = '<span class="month">' + date.strftime('%b').upcase + '</span> '
+      result += date.strftime('<span class="day">%d</span> ')
+      result += date.strftime('<span class="year">%Y</span> ')
+      result
+    end
+
+  end
+
+end
+