jekyll sitemap generator

1 files changed, 297 insertions, 0 deletions

diff --git a/site/src/jekyll/_plugins/sitemap_generator.rb b/site/src/jekyll/_plugins/sitemap_generator.rb
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+++ b/site/src/jekyll/_plugins/sitemap_generator.rb
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+# Sitemap.xml Generator is a Jekyll plugin that generates a sitemap.xml file by 
+# traversing all of the available posts and pages.
+# 
+# See readme file for documenation
+# 
+# Updated to use config file for settings by Daniel Groves
+# Site: http://danielgroves.net
+# 
+# Author: Michael Levin
+# Site: http://www.kinnetica.com
+# Distributed Under A Creative Commons License
+#   - http://creativecommons.org/licenses/by/3.0/
+
+require 'rexml/document'
+
+module Jekyll
+
+  class Post
+    attr_accessor :name
+
+    def full_path_to_source
+      File.join(@base, @name)
+    end
+    
+    def path_to_source
+      File.join(@name)
+    end
+
+    def location_on_server(my_url)
+      "#{my_url}#{url}"
+    end
+  end
+
+  class Page
+    attr_accessor :name
+
+    def full_path_to_source
+      File.join(@base, @dir, @name)
+    end
+    
+    def path_to_source
+      File.join(@dir, @name)
+    end
+
+    def location_on_server(my_url)
+      location = "#{my_url}#{url}"
+      location.gsub(/index.html$/, "")
+    end
+  end
+
+
+  class Layout
+    def full_path_to_source
+      File.join(@base, @name)
+    end
+  end
+
+  # Recover from strange exception when starting server without --auto
+  class SitemapFile < StaticFile
+    def write(dest)
+      begin
+        super(dest)
+      rescue
+      end
+
+      true
+    end
+  end
+
+  class SitemapGenerator < Generator
+
+    # Config defaults
+    SITEMAP_FILE_NAME = "/sitemap.xml"
+    EXCLUDE = ["/atom.xml", "/feed.xml", "/feed/index.xml"]
+    INCLUDE_POSTS = ["/index.html"] 
+    CHANGE_FREQUENCY_NAME = "change_frequency"
+    PRIORITY_NAME = "priority"
+    
+    # Valid values allowed by sitemap.xml spec for change frequencies
+    VALID_CHANGE_FREQUENCY_VALUES = ["always", "hourly", "daily", "weekly",
+      "monthly", "yearly", "never"] 
+
+    # Goes through pages and posts and generates sitemap.xml file
+    #
+    # Returns nothing
+    def generate(site)
+      # Configuration
+      sitemap_config = site.config['sitemap'] || {}
+      @config = {}
+      @config['filename'] = sitemap_config['filename'] || SITEMAP_FILE_NAME
+      @config['change_frequency_name'] = sitemap_config['change_frequency_name'] || CHANGE_FREQUENCY_NAME
+      @config['priority_name'] = sitemap_config['priority_name'] || PRIORITY_NAME
+      @config['exclude'] = sitemap_config['exclude'] || EXCLUDE
+      @config['include_posts'] = sitemap_config['include_posts'] || INCLUDE_POSTS
+
+      sitemap = REXML::Document.new << REXML::XMLDecl.new("1.0", "UTF-8")
+
+      urlset = REXML::Element.new "urlset"
+      urlset.add_attribute("xmlns", 
+        "http://www.sitemaps.org/schemas/sitemap/0.9")
+
+      @last_modified_post_date = fill_posts(site, urlset)
+      fill_pages(site, urlset)
+
+      sitemap.add_element(urlset)
+
+      # Create destination directory if it doesn't exist yet. Otherwise, we cannot write our file there.
+      Dir::mkdir(site.dest) if !File.directory? site.dest
+
+      # File I/O: create sitemap.xml file and write out pretty-printed XML
+      filename = @config['filename']
+      file = File.new(File.join(site.dest, filename), "w")
+      formatter = REXML::Formatters::Pretty.new(4)
+      formatter.compact = true
+      formatter.write(sitemap, file)
+      file.close
+
+      # Keep the sitemap.xml file from being cleaned by Jekyll
+      site.static_files << Jekyll::SitemapFile.new(site, site.dest, "/", filename)
+    end
+
+    # Create url elements for all the posts and find the date of the latest one
+    #
+    # Returns last_modified_date of latest post
+    def fill_posts(site, urlset)
+      last_modified_date = nil
+      site.posts.each do |post|
+        if !excluded?(site, post.name)
+          url = fill_url(site, post)
+          urlset.add_element(url)
+        end
+
+        path = post.full_path_to_source
+        date = File.mtime(path)
+        last_modified_date = date if last_modified_date == nil or date > last_modified_date
+      end
+
+      last_modified_date
+    end
+
+    # Create url elements for all the normal pages and find the date of the
+    # index to use with the pagination pages
+    #
+    # Returns last_modified_date of index page
+    def fill_pages(site, urlset)
+      site.pages.each do |page|
+        if !excluded?(site, page.path_to_source)
+          path = page.full_path_to_source
+          if File.exists?(path)
+            url = fill_url(site, page)
+            urlset.add_element(url)
+          end
+        end
+      end
+    end
+
+    # Fill data of each URL element: location, last modified, 
+    # change frequency (optional), and priority.
+    #
+    # Returns url REXML::Element
+    def fill_url(site, page_or_post)
+      url = REXML::Element.new "url"
+
+      loc = fill_location(site, page_or_post)
+      url.add_element(loc)
+
+      lastmod = fill_last_modified(site, page_or_post)
+      url.add_element(lastmod) if lastmod
+
+
+
+      if (page_or_post.data[@config['change_frequency_name']])
+        change_frequency = 
+          page_or_post.data[@config['change_frequency_name']].downcase
+          
+        if (valid_change_frequency?(change_frequency))
+          changefreq = REXML::Element.new "changefreq"
+          changefreq.text = change_frequency
+          url.add_element(changefreq)
+        else
+          puts "ERROR: Invalid Change Frequency In #{page_or_post.name}"
+        end
+      end
+
+      if (page_or_post.data[@config['priority_name']])
+        priority_value = page_or_post.data[@config['priority_name']]
+        if valid_priority?(priority_value)
+          priority = REXML::Element.new "priority"
+          priority.text = page_or_post.data[@config['priority_name']]
+          url.add_element(priority)
+        else
+          puts "ERROR: Invalid Priority In #{page_or_post.name}"
+        end
+      end
+
+      url
+    end
+
+    # Get URL location of page or post 
+    #
+    # Returns the location of the page or post
+    def fill_location(site, page_or_post)
+      loc = REXML::Element.new "loc"
+      url = site.config['url']
+      loc.text = page_or_post.location_on_server(url)
+
+      loc
+    end
+
+    # Fill lastmod XML element with the last modified date for the page or post.
+    #
+    # Returns lastmod REXML::Element or nil
+    def fill_last_modified(site, page_or_post)
+      path = page_or_post.full_path_to_source
+
+      lastmod = REXML::Element.new "lastmod"
+      date = File.mtime(path)
+      latest_date = find_latest_date(date, site, page_or_post)
+
+      if @last_modified_post_date == nil
+        # This is a post
+        lastmod.text = latest_date.iso8601
+      else
+        # This is a page
+        if posts_included?(site, page_or_post.path_to_source)
+          # We want to take into account the last post date
+          final_date = greater_date(latest_date, @last_modified_post_date)
+          lastmod.text = final_date.iso8601
+        else
+          lastmod.text = latest_date.iso8601
+        end
+      end
+      lastmod
+    end
+
+    # Go through the page/post and any implemented layouts and get the latest
+    # modified date
+    #
+    # Returns formatted output of latest date of page/post and any used layouts
+    def find_latest_date(latest_date, site, page_or_post)
+      layouts = site.layouts
+      layout = layouts[page_or_post.data["layout"]]
+      while layout
+        path = layout.full_path_to_source
+        date = File.mtime(path)
+
+        latest_date = date if (date > latest_date)
+
+        layout = layouts[layout.data["layout"]]
+      end
+
+      latest_date
+    end
+
+    # Which of the two dates is later
+    #
+    # Returns latest of two dates
+    def greater_date(date1, date2)
+      if (date1 >= date2) 
+        date1
+      else 
+        date2 
+      end
+    end
+
+    # Is the page or post listed as something we want to exclude?
+    #
+    # Returns boolean
+    def excluded?(site, name)
+      @config['exclude'].include? name
+    end
+
+    def posts_included?(site, name)
+      @config['include_posts'].include? name
+    end
+
+    # Is the change frequency value provided valid according to the spec
+    #
+    # Returns boolean
+    def valid_change_frequency?(change_frequency)
+      VALID_CHANGE_FREQUENCY_VALUES.include? change_frequency
+    end
+
+    # Is the priority value provided valid according to the spec
+    #
+    # Returns boolean
+    def valid_priority?(priority)
+      begin
+        priority_val = Float(priority)
+        return true if priority_val >= 0.0 and priority_val <= 1.0
+      rescue ArgumentError
+      end
+
+      false
+    end
+  end
+end