Rev 2 of my cowsay serv.

cowsay-server-02.rb

require 'socket'

module CowSay
    class Server
        def initialize(port)
            # Create the underlying socket server
            @server = TCPServer.new(port)
            puts "Listening on port #{@server.local_address.ip_port}"
        end

        def start
            # TODO Currently this server can only accept one connection at at
            # time. Do I want to change that so I can process multiple requests
            # at once?
            Socket.accept_loop(@server) do |connection|
                handle(connection)
                connection.close
            end
        end

        # Find a value in a line for a given key 
        def find_value_for_key(key, document)

            retval = nil

            re = /^#{key} (.*)/
            md = re.match(document)
           
            if md != nil
                retval = md[1]
            end

            retval
        end

        # Parse the document that is sent by the client and convert it into a
        # hash table.
        def parse(document)
            commands = Hash.new

            message_value = find_value_for_key("MESSAGE", document)
            if message_value == nil then
                $stderr.puts "ERROR: Empty message"
            end
            commands[:message] = message_value

            body_value = find_value_for_key("BODY", document)
            if body_value == nil then
                commands[:body] = "default"
            else
                commands[:body] = body_value
            end

            commands
        end

        def handle(connection)
            # TODO Read is going to block until EOF. I need to use something
            # different that will work without an EOF. 
            request = connection.read

            # The current API will accept a message only from netcat. This
            # message is what the cow will say. Soon I will add support for
            # more features, like choosing your cow.

            # Write back the result of the hash operation
            connection.write process(parse(request))
        end

        def process(commands)
            # TODO Currently I can't capture STDERR output. This is
            # definitely a problem when someone passes a bogus 
            # body file name.
            `cowsay -f #{commands[:body]} "#{commands[:message]}"`
        end
    end
end

server = CowSay::Server.new(4481)
server.start