module Rack # Rack::URLMap takes a hash mapping urls or paths to apps, and # dispatches accordingly. Support for HTTP/1.1 host names exists if # the URLs start with http:// or https://. # # URLMap modifies the SCRIPT_NAME and PATH_INFO such that the part # relevant for dispatch is in the SCRIPT_NAME, and the rest in the # PATH_INFO. This should be taken care of when you need to # reconstruct the URL in order to create links. # # URLMap dispatches in such a way that the longest paths are tried # first, since they are most specific. class URLMap def initialize(map) @mapping = map.map { |location, app| if location =~ %r{\Ahttps?://(.*?)(/.*)} host, location = $1, $2 else host = nil end unless location[0] == ?/ raise ArgumentError, "paths need to start with /" end location = location.chomp('/') [host, location, app] }.sort_by { |(h, l, a)| [-l.size, h.to_s.size] } # Longest path first end def call(env) path = env["PATH_INFO"].to_s.squeeze("/") script_name = env['SCRIPT_NAME'] hHost, sName, sPort = env.values_at('HTTP_HOST','SERVER_NAME','SERVER_PORT') @mapping.each { |host, location, app| next unless (hHost == host || sName == host \ || (host.nil? && (hHost == sName || hHost == sName+':'+sPort))) next unless location == path[0, location.size] next unless path[location.size] == nil || path[location.size] == ?/ return app.call( env.merge( 'SCRIPT_NAME' => (script_name + location), 'PATH_INFO' => path[location.size..-1])) } [404, {"Content-Type" => "text/plain"}, ["Not Found: #{path}"]] end end end