Commit b66ab629 authored by Guido Trotter's avatar Guido Trotter
Browse files

daemon.AsyncTerminatedMessageStream



This is the counterpart of the AsyncStreamServer can be used to handle
connected sockets returned from connected clients if the protocol is a
terminator separated message stream. Nothing in this class is server
specific though: it can be used as a client as well, if the client is
implemented inside an asyncore daemon.
Signed-off-by: default avatarGuido Trotter <ultrotter@google.com>
Reviewed-by: default avatarMichael Hanselmann <hansmi@google.com>
parent a4b605ae
......@@ -23,6 +23,7 @@
import asyncore
import asynchat
import os
import signal
import logging
......@@ -160,6 +161,82 @@ class AsyncStreamServer(GanetiBaseAsyncoreDispatcher):
raise NotImplementedError
class AsyncTerminatedMessageStream(asynchat.async_chat):
"""A terminator separated message stream asyncore module.
Handles a stream connection receiving messages terminated by a defined
separator. For each complete message handle_message is called.
"""
def __init__(self, connected_socket, peer_address, terminator, family):
"""AsyncTerminatedMessageStream constructor.
@type connected_socket: socket.socket
@param connected_socket: connected stream socket to receive messages from
@param peer_address: family-specific peer address
@type terminator: string
@param terminator: terminator separating messages in the stream
@type family: integer
@param family: socket family
"""
# python 2.4/2.5 uses conn=... while 2.6 has sock=... we have to cheat by
# using a positional argument rather than a keyword one.
asynchat.async_chat.__init__(self, connected_socket)
self.connected_socket = connected_socket
# on python 2.4 there is no "family" attribute for the socket class
# FIXME: when we move to python 2.5 or above remove the family parameter
#self.family = self.connected_socket.family
self.family = family
self.peer_address = peer_address
self.terminator = terminator
self.set_terminator(terminator)
self.ibuffer = []
self.next_incoming_message = 0
# this method is overriding an asynchat.async_chat method
def collect_incoming_data(self, data):
self.ibuffer.append(data)
# this method is overriding an asynchat.async_chat method
def found_terminator(self):
message = "".join(self.ibuffer)
self.ibuffer = []
message_id = self.next_incoming_message
self.next_incoming_message += 1
self.handle_message(message, message_id)
def handle_message(self, message, message_id):
"""Handle a terminated message.
@type message: string
@param message: message to handle
@type message_id: integer
@param message_id: stream's message sequence number
"""
pass
# TODO: move this method to raise NotImplementedError
# raise NotImplementedError
def close_log(self):
logging.info("Closing connection from %s",
FormatAddress(self.family, self.peer_address))
self.close()
# this method is overriding an asyncore.dispatcher method
def handle_expt(self):
self.close_log()
# this method is overriding an asyncore.dispatcher method
def handle_error(self):
"""Log an error in handling any request, and proceed.
"""
logging.exception("Error while handling asyncore request")
self.close_log()
class AsyncUDPSocket(GanetiBaseAsyncoreDispatcher):
"""An improved asyncore udp socket.
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment