blog/plugins/gist_tag.rb

95 lines
2.8 KiB
Ruby

# A Liquid tag for Jekyll sites that allows embedding Gists and showing code for non-JavaScript enabled browsers and readers.
# by: Brandon Tilly
# Source URL: https://gist.github.com/1027674
# Post http://brandontilley.com/2011/01/31/gist-tag-for-jekyll.html
#
# Example usage: {% gist 1027674 gist_tag.rb %} //embeds a gist for this plugin
require 'cgi'
require 'digest/md5'
require 'net/https'
require 'uri'
module Jekyll
class GistTag < Liquid::Tag
def initialize(tag_name, text, token)
super
@text = text
@cache_disabled = false
@cache_folder = File.expand_path "../_gist_cache", File.dirname(__FILE__)
FileUtils.mkdir_p @cache_folder
end
def render(context)
if parts = @text.match(/([\d]*) (.*)/)
gist, file = parts[1].strip, parts[2].strip
script_url = script_url_for gist, file
code = get_cached_gist(gist, file) || get_gist_from_web(gist, file)
html_output_for script_url, code
else
""
end
end
def html_output_for(script_url, code)
code = CGI.escapeHTML code
<<-HTML
<div><script src='#{script_url}'></script>
<noscript><pre><code>#{code}</code></pre></noscript></div>
HTML
end
def script_url_for(gist_id, filename)
"https://gist.github.com/#{gist_id}.js?file=#{filename}"
end
def get_gist_url_for(gist, file)
"https://raw.github.com/gist/#{gist}/#{file}"
end
def cache(gist, file, data)
cache_file = get_cache_file_for gist, file
File.open(cache_file, "w") do |io|
io.write data
end
end
def get_cached_gist(gist, file)
return nil if @cache_disabled
cache_file = get_cache_file_for gist, file
File.read cache_file if File.exist? cache_file
end
def get_cache_file_for(gist, file)
bad_chars = /[^a-zA-Z0-9\-_.]/
gist = gist.gsub bad_chars, ''
file = file.gsub bad_chars, ''
md5 = Digest::MD5.hexdigest "#{gist}-#{file}"
File.join @cache_folder, "#{gist}-#{file}-#{md5}.cache"
end
def get_gist_from_web(gist, file)
gist_url = get_gist_url_for gist, file
raw_uri = URI.parse gist_url
https = Net::HTTP.new raw_uri.host, raw_uri.port
https.use_ssl = true
https.verify_mode = OpenSSL::SSL::VERIFY_NONE
request = Net::HTTP::Get.new raw_uri.request_uri
data = https.request request
data = data.body
cache gist, file, data unless @cache_disabled
data
end
end
class GistTagNoCache < GistTag
def initialize(tag_name, text, token)
super
@cache_disabled = true
end
end
end
Liquid::Template.register_tag('gist', Jekyll::GistTag)
Liquid::Template.register_tag('gistnocache', Jekyll::GistTagNoCache)