In case it's any use, here are a few snippets of fake POP3 server I wrote a
while back.
Here was my first attempt: the POP3 server instance is represented by its
own object.
···
On Sat, Dec 14, 2002 at 12:20:29AM +0900, Shannon Fang wrote:
I am learning how to use Ruby to write a TCP Server. I used the sample code
in PickAxe, it worked fine, but I have no idea how I can let the program
connect more than one client? Do I need to use thread?
Can anyone show me how to do this by writing a echo server which can
connect multiple clients?
-------------------------------------------------------------------------
#!/usr/local/bin/ruby -w
class Testserver
def initialize(session)
@session = session
end
def run
@session.print "+OK I am a fake POP3 server\n"
while line = @session.gets
case line
when /quit/i
break
else
@session.print "-ERR I don't understand #{line}"
end
end
@session.print "+OK bye\n"
@session.close
end
end
require 'socket'
port = (ARGV[0] || 110).to_i
server = TCPServer.new('0.0.0.0', port)
while (session = server.accept)
Thread.new do
Testserver.new(session).run
end
end
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The messy thing with that is having to keep referencing the instance
variable for the TCPSocket every time you want to input or output.
I tried subclassing TCPSocket, but I couldn't work out how to convert the
TCPSocket returned by server.accept into an instance of the subclass.
In the end, the tidiest solution seemed to be to dynamically add a 'run'
method to each TCPSocket as it is created:
-------------------------------------------------------------------------
#!/usr/local/bin/ruby -w
module Pop3
def run
print "+OK I am a fake POP3 server\n"
while line = gets
case line
when /quit/i
break
else
print "-ERR I don't understand #{line}"
end
end
print "+OK bye\n"
close
end
end
require 'socket'
port = (ARGV[0] || 110).to_i
server = TCPServer.new('0.0.0.0', port)
while (session = server.accept)
session.extend Pop3
Thread.new do
session.run
end
end
-------------------------------------------------------------------------
It might not be quite as efficient though, although I don't know how much
overhead is associated with extending an object in this way.
Hope this gives you something to play with...
Regards,
Brian.
