Ruby XML-RPC over Unix Domain Socket (SCGI)

xmlrpcs.rb

# vim: ai ts=2
require 'xmlrpc/client'

module XMLRPC

class LocalClient < Client

	def initialize(path, timeout)
		super("unix:", path, 0, nil, nil, nil, nil, false, timeout)
	end

	private

	def net_http(host, port, proxy_host, proxy_port)
		LocalHTTP.new @path, port, proxy_host, proxy_port
	end

	class LocalHTTP < Net::HTTP
		
		def connect
			D "opening unix socket #{@address}"
			s = timeout(@open_timeout) { UNIXSocket.open(@address) }
			D "opened"
			@socket = ::Net::BufferedIO.new(s)
			@socket.read_timeout = @read_timeout
			@socket.continue_timeout = @continue_timeout
			@socket.debug_output = @debug_output
			@socket.instance_variable_set('@scgi_http_hack', true)
			on_connect
		end

		def request_post(path, data, initheader = nil, &block)
			request SCGIPost.new(path, initheader), data, &block
		end

		private

		module SCGISupport
			def encode_netstring(s)
				sprintf('%d:%s', s.length, s)
			end
			def make_headers(headers)
				headers.flatten.join("\0") + "\0"
			end
			def scgi_headers(data, headers=[])
				headers=make_headers([
					['CONTENT_LENGTH', data.length.to_s],
					['SCGI', '1']
				] + headers)
				encode_netstring(headers)
			end
		end

		class SCGIPost < Net::HTTP::Post
			private
			include SCGISupport
			def write_header(sock, ver, path)
			end
			def send_request_with_body(sock, ver, path, body)
				self.content_length = body.bytesize
				delete 'Transfer-Encoding'
				supply_default_content_type
				write_header sock, ver, path
				wait_for_continue sock, ver if sock.continue_timeout
				sock.write scgi_headers(body)+","+body
			end
		end
	end
end

class ::Net::HTTPResponse
	class << self
		alias_method :read_new_noscgi, :read_new
		def read_new(sock)
			if is_scgi(sock) then
				read_new_scgi(sock)
			else
				read_new_noscgi(sock)
			end
		end
		private
		def read_new_scgi(sock)
			httpv = "1.0"
			code = nil
			msg = nil
			headers = []
			each_response_header(sock) do |k,v|
				if k == 'Status' then
					code, msg = read_status_header(v)
				else
					headers << [k,v]
				end
			end
			res = response_class(code).new(httpv, code, msg)
			headers.each do |k,v|
				res.add_field k, v
			end
			res
		end
		def read_status_header(str)
			m = /\A(\d\d\d)\s*(.*)\z/in.match(str) or
				raise Net::HTTPBadResponse, "wrong status header: #{str.dump}"
			m.captures
		end
		def is_scgi(sock)
			sock.instance_variable_get('@scgi_http_hack')
		end
	end
end

end