1 # Jekyll plugin for generating an rss 2.0 feed for posts
  2 #
  3 # Usage: place this file in the _plugins directory and set the required configuration
  4 #        attributes in the _config.yml file
  5 #
  6 # Uses the following attributes in _config.yml:
  7 #   name           - the name of the site
  8 #   url            - the url of the site
  9 #   description    - (optional) a description for the feed (if not specified will be generated from name)
 10 #   author         - (optional) the author of the site (if not specified will be left blank)
 11 #   copyright      - (optional) the copyright of the feed (if not specified will be left blank)
 12 #   rss_path       - (optional) the path to the feed (if not specified "/" will be used)
 13 #   rss_name       - (optional) the name of the rss file (if not specified "rss.xml" will be used)
 14 #   rss_post_limit - (optional) the number of posts in the feed
 15 #
 16 # Author: Assaf Gelber <assaf.gelber@gmail.com>
 17 # Site: http://agelber.com
 18 # Source: http://github.com/agelber/jekyll-rss
 19 #
 20 # Distributed under the MIT license
 21 # Copyright Assaf Gelber 2013
 22 
 23 module Jekyll
 24   class RssFeed < Page; end
 25 
 26   class RssGenerator < Generator
 27     priority :low
 28     safe true
 29 
 30     # Generates an rss 2.0 feed
 31     #
 32     # site - the site
 33     #
 34     # Returns nothing
 35     def generate(site)
 36       require 'rss'
 37 
 38       # Create the rss with the help of the RSS module
 39       rss = RSS::Maker.make("2.0") do |maker|
 40         maker.channel.title = site.config['name']
 41         maker.channel.link = site.config['url']
 42         maker.channel.description = site.config['description'] || "RSS feed for #{site.config['name']}"
 43         maker.channel.author = site.config["author.name"]
 44         maker.channel.updated = site.posts.map { |p| p.date  }.max
 45         maker.channel.copyright = site.config['copyright']
 46 
 47         post_limit = (site.config['rss_post_limit'] - 1 rescue site.posts.count)
 48 
 49         site.posts.reverse[0..post_limit].each do |post|
 50           post.render(site.layouts, site.site_payload)
 51           maker.items.new_item do |item|
 52             link = "#{site.config['url']}#{post.url}"
 53             item.guid.content = link
 54             item.title = post.title
 55             item.link = link
 56             item.description = post.excerpt
 57             item.updated = post.date
 58           end
 59         end
 60       end
 61 
 62       # File creation and writing
 63       rss_path = ensure_slashes(site.config['rss_path'] || "/")
 64       rss_name = site.config['rss_name'] || "rss.xml"
 65       full_path = File.join(site.dest, rss_path)
 66       ensure_dir(full_path)
 67       File.open("#{full_path}#{rss_name}", "w") { |f| f.write(rss) }
 68 
 69       # Add the feed page to the site pages
 70       site.pages << Jekyll::RssFeed.new(site, site.dest, rss_path, rss_name)
 71     end
 72 
 73     private
 74 
 75     # Ensures the given path has leading and trailing slashes
 76     #
 77     # path - the string path
 78     #
 79     # Return the path with leading and trailing slashes
 80     def ensure_slashes(path)
 81       ensure_leading_slash(ensure_trailing_slash(path))
 82     end
 83 
 84     # Ensures the given path has a leading slash
 85     #
 86     # path - the string path
 87     #
 88     # Returns the path with a leading slash
 89     def ensure_leading_slash(path)
 90       path[0] == "/" ? path : "/#{path}"
 91     end
 92 
 93     # Ensures the given path has a trailing slash
 94     #
 95     # path - the string path
 96     #
 97     # Returns the path with a trailing slash
 98     def ensure_trailing_slash(path)
 99       path[-1] == "/" ? path : "#{path}/"
100     end
101 
102     # Ensures the given directory exists
103     #
104     # path - the string path of the directory
105     #
106     # Returns nothing
107     def ensure_dir(path)
108       FileUtils.mkdir_p(path)
109     end
110 
111   end
112 end