instiki/app/metal/itex.rb
2010-03-02 13:59:50 -06:00

76 lines
1.9 KiB
Ruby

# Allow the metal piece to run in isolation
require(File.dirname(__FILE__) + "/../../config/environment") unless defined?(Rails)
require 'stringsupport'
class Itex
def self.call(env)
if env["PATH_INFO"] =~ /^\/itex/
[200, {"Content-Type" => "application/xml"}, [response(env)]]
else
[404, {"Content-Type" => "text/html"}, ["Not Found"]]
end
end
private
# plugable XML parser; falls back to REXML
begin
require 'nokogiri'
def self.xmlparse(text)
Nokogiri::XML(text) { |config| config.options = Nokogiri::XML::ParseOptions::STRICT }
end
rescue LoadError
require 'rexml/document'
def self.xmlparse(text)
REXML::Document.new(text)
end
end
#error message to return
def self.error(str)
"<math xmlns='http://www.w3.org/1998/Math/MathML' display='inline'><merror><mtext>" +
str + "</mtext></merror></math>"
end
# itex2MML parser
begin
require 'itextomml'
def self.parse_itex(tex, filter)
Itex2MML::Parser.new.send(filter, tex).to_utf8
end
rescue LoadError
def self.parse_itex(tex, filter)
error("Please install the itex2MML Ruby bindings.")
end
end
# the actual response
def self.response(env)
params = Rack::Request.new(env).params
tex = (params['tex'] || '').purify.strip
case params['display']
when 'block'
filter = :block_filter
else
filter = :inline_filter
end
return "<math xmlns='http://www.w3.org/1998/Math/MathML' display='" +
filter.to_s[/(.*?)_filter/] + "'/>" if tex == ''
begin
doc = parse_itex(tex, filter)
# make sure the result is well-formed, before sending it off
begin
xmlparse(doc)
rescue
return error("Ill-formed XML.")
end
return doc
rescue Itex2MML::Error => e
error(e.to_s)
rescue
error("Unknown Error")
end
end
end