Python in a Nutshell

Name

set_terminator

Synopsis

                           x.set_terminator(terminator)

Your class X normally doesn’t override this method. terminator is normally '\r\n', the line terminator specified by most Internet protocols. terminator can also be None, to disable calls to found_terminator.

Example 19-8 uses module asynchat to reimplement the server of Example 19-7, with small differences due to using class asynchat.async_chat instead of class asyncore.dispatcher_with_send. To highlight async_chat’s typical use, Example 19-8 responds (by echoing the received data back to the client, like all other server examples in this chapter) only when it has received a complete line (i.e., one ending with \n).

Example 19-8. Asynchronous TCP echo server using asynchat

import asyncore, asynchat, socket class MainServerSocket(asyncore.dispatcher): def __init_ _(self, port): print 'initing MSS' asyncore.dispatcher.__init_ _(self) self.create_socket(socket.AF_INET, socket.SOCK_STREAM) self.bind(('',port)) self.listen(5) def handle_accept(self): newSocket, address = self.accept( ) print "Connected from", address SecondaryServerSocket(newSocket) class SecondaryServerSocket(asynchat.async_chat): def __init_ _(self, *args): print 'initing SSS' asynchat.async_chat.__init_ _(self, *args) self.set_terminator('\n') self.data = [] def collect_incoming_data(self, data): self.data.append(data) def found_terminator(self): self.push(''.join(self.data)) self.data = [] def handle_close(self): print "Disconnected from", self.getpeername( ) ...