#
# NEPI, a framework to manage network experiments
# Copyright (C) 2014 INRIA
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation;
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Author: Alina Quereilhac <alina.quereilhac@inria.fr>
import base64
import cPickle
import errno
import logging
import os
import socket
import sys
from optparse import OptionParser, SUPPRESS_HELP
from ns3wrapper import NS3Wrapper
[docs]class NS3WrapperMessage:
CREATE = "CREATE"
FACTORY = "FACTORY"
INVOKE = "INVOKE"
SET = "SET"
GET = "GET"
FLUSH = "FLUSH"
START = "START"
STOP = "STOP"
SHUTDOWN = "SHUTDOWN"
[docs]def handle_message(ns3_wrapper, msg_type, args, kwargs):
if msg_type == NS3WrapperMessage.SHUTDOWN:
ns3_wrapper.shutdown()
return "BYEBYE"
if msg_type == NS3WrapperMessage.STOP:
time = kwargs.get("time")
ns3_wrapper.stop(time=time)
return "STOPPED"
if msg_type == NS3WrapperMessage.START:
ns3_wrapper.start()
return "STARTED"
if msg_type == NS3WrapperMessage.CREATE:
clazzname = args.pop(0)
return ns3_wrapper.create(clazzname, *args)
if msg_type == NS3WrapperMessage.FACTORY:
type_name = args.pop(0)
return ns3_wrapper.factory(type_name, **kwargs)
if msg_type == NS3WrapperMessage.INVOKE:
uuid = args.pop(0)
operation = args.pop(0)
return ns3_wrapper.invoke(uuid, operation, *args, **kwargs)
if msg_type == NS3WrapperMessage.GET:
uuid = args.pop(0)
name = args.pop(0)
return ns3_wrapper.get(uuid, name)
if msg_type == NS3WrapperMessage.SET:
uuid = args.pop(0)
name = args.pop(0)
value = args.pop(0)
return ns3_wrapper.set(uuid, name, value)
if msg_type == NS3WrapperMessage.FLUSH:
# Forces flushing output and error streams.
# NS-3 output will stay unflushed until the program exits or
# explicit invocation flush is done
sys.stdout.flush()
sys.stderr.flush()
ns3_wrapper.logger.debug("FLUSHED")
return "FLUSHED"
[docs]def open_socket(socket_name):
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
sock.bind(socket_name)
return sock
[docs]def close_socket(sock):
try:
sock.close()
except:
pass
[docs]def recv_msg(conn):
msg = []
chunk = ''
while '\n' not in chunk:
try:
chunk = conn.recv(1024)
except (OSError, socket.error), e:
if e[0] != errno.EINTR:
raise
# Ignore eintr errors
continue
if chunk:
msg.append(chunk)
else:
# empty chunk = EOF
break
msg = ''.join(msg).strip()
# The message is formatted as follows:
# MESSAGE_TYPE|args|kwargs
#
# where MESSAGE_TYPE, args and kwargs are pickld and enoded in base64
def decode(item):
item = base64.b64decode(item).rstrip()
return cPickle.loads(item)
decoded = map(decode, msg.split("|"))
# decoded message
dmsg_type = decoded.pop(0)
dargs = list(decoded.pop(0)) # transforming touple into list
dkwargs = decoded.pop(0)
return (dmsg_type, dargs, dkwargs)
[docs]def send_reply(conn, reply):
encoded = base64.b64encode(cPickle.dumps(reply))
conn.send("%s\n" % encoded)
[docs]def get_options():
usage = ("usage: %prog -S <socket-name> -L <ns-log> -D <enable-dump> -v ")
parser = OptionParser(usage = usage)
parser.add_option("-S", "--socket-name", dest="socket_name",
help = "Name for the unix socket used to interact with this process",
default = "tap.sock", type="str")
parser.add_option("-L", "--ns-log", dest="ns_log",
help = "NS_LOG environmental variable to be set",
default = "", type="str")
parser.add_option("-D", "--enable-dump", dest="enable_dump",
help = "Enable dumping the remote executed ns-3 commands to a script "
"in order to later reproduce and debug the experiment",
action = "store_true",
default = False)
parser.add_option("-v", "--verbose",
help="Print debug output",
action="store_true",
dest="verbose", default=False)
(options, args) = parser.parse_args()
return (options.socket_name, options.verbose, options.ns_log,
options.enable_dump)
[docs]def run_server(socket_name, level = logging.INFO, ns_log = None,
enable_dump = False):
# Sets NS_LOG environmental variable for NS debugging
if ns_log:
os.environ["NS_LOG"] = ns_log
###### ns-3 wrapper instantiation
ns3_wrapper = NS3Wrapper(loglevel=level, enable_dump = enable_dump)
ns3_wrapper.logger.info("STARTING...")
# create unix socket to receive instructions
sock = open_socket(socket_name)
sock.listen(0)
# wait for messages to arrive and process them
stop = False
while not stop:
conn, addr = sock.accept()
conn.settimeout(30)
try:
(msg_type, args, kwargs) = recv_msg(conn)
except socket.timeout, e:
# Ingore time-out
close_socket(conn)
continue
if not msg_type:
# Ignore - connection lost
close_socket(conn)
continue
if msg_type == NS3WrapperMessage.SHUTDOWN:
stop = True
try:
reply = handle_message(ns3_wrapper, msg_type, args, kwargs)
except:
import traceback
err = traceback.format_exc()
ns3_wrapper.logger.error(err)
close_socket(conn)
raise
try:
send_reply(conn, reply)
except socket.error:
import traceback
err = traceback.format_exc()
ns3_wrapper.logger.error(err)
close_socket(conn)
raise
close_socket(conn)
close_socket(sock)
ns3_wrapper.logger.info("EXITING...")
if __name__ == '__main__':
(socket_name, verbose, ns_log, enable_dump) = get_options()
## configure logging
FORMAT = "%(asctime)s %(name)s %(levelname)-4s %(message)s"
level = logging.DEBUG if verbose else logging.INFO
logging.basicConfig(format = FORMAT, level = level)
## Run the server
run_server(socket_name, level, ns_log, enable_dump)