NS3Wrapper server and client

[nepi.git] / src / nepi / resources / ns3 / ns3server.py

diff --git a/src/nepi/resources/ns3/ns3server.py b/src/nepi/resources/ns3/ns3server.py
new file mode 100644 (file)
index 0000000..f538259
--- /dev/null
+++ b/src/nepi/resources/ns3/ns3server.py
@@ -0,0 +1,183 @@
+#
+#    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 as published by
+#    the Free Software Foundation, either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    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 socket
+from optparse import OptionParser, SUPPRESS_HELP
+
+from ns3wrapper import NS3Wrapper
+
+class NS3WrapperMessage:
+    CREATE = "CREATE"
+    INVOKE = "INVOKE"
+    SET = "SET"
+    GET = "GET"
+    TRACE = "TRACE"
+    START = "START"
+    STOP = "STOP"
+    SHUTDOWN = "SHUTDOWN"
+
+def handle_message(ns3_wrapper, msg, args):
+    if msg == NS3WrapperMessage.SHUTDOWN:
+        ns3_wrapper.shutdown()
+        return "BYEBYE"
+    
+    if msg == NS3WrapperMessage.STOP:
+        time = None
+        if args:
+            time = args[0]
+
+        ns3_wrapper.stop(time=time)
+        return "STOPPED"
+
+    if msg == NS3WrapperMessage.START:
+        ns3_wrapper.start()
+        return "STARTED"
+
+    if msg == NS3WrapperMessage.CREATE:
+        clazzname = args.pop(0)
+        
+        uuid = ns3_wrapper.create(clazzname, *args)
+        return uuid
+
+    if msg == NS3WrapperMessage.INVOKE:
+        uuid = args.pop(0)
+        operation = args.pop(0)
+        
+        uuid = ns3_wrapper.invoke(uuid, operation, *args)
+        return uuid
+
+    if msg == NS3WrapperMessage.GET:
+        uuid = args.pop(0)
+        name = args.pop(0)
+
+        value = ns3_wrapper.get(uuid, name)
+        return value
+
+    if msg == NS3WrapperMessage.SET:
+        uuid = args.pop(0)
+        name = args.pop(0)
+        value = args.pop(0)
+
+        value = ns3_wrapper.set(uuid, name, value)
+        return value
+ 
+    if msg == NS3WrapperMessage.TRACE:
+        return "NOT IMPLEMENTED"
+
+def create_socket(socket_name):
+    sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    sock.bind(socket_name)
+    return sock
+
+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).split('\n')[0]
+
+    # The message might have arguments that will be appended
+    # as a '|' separated list after the message identifier
+    def decode(arg):
+        arg = base64.b64decode(arg).rstrip()
+        return cPickle.loads(arg)
+
+    dargs = map(decode, msg.split("|"))
+
+    # decoded message
+    dmsg = dargs.pop(0)
+
+    return (dmsg, dargs)
+
+def send_reply(conn, reply):
+    encoded = base64.b64encode(cPickle.dumps(reply))
+    conn.send("%s\n" % encoded)
+
+def get_options():
+    usage = ("usage: %prog -S <socket-name>")
+    
+    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")
+
+    (options, args) = parser.parse_args()
+    
+    return options.socket_name
+
+def run_server(socket_name): 
+    ns3_wrapper = NS3Wrapper()
+
+    # create unix socket to receive instructions
+    sock = create_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(5)
+
+        try:
+            (msg, args) = recv_msg(conn)
+        except socket.timeout, e:
+            # Ingore time-out
+            continue
+
+        if not msg:
+            # Ignore - connection lost
+            break
+ 
+        ns3_wrapper.logger.debug("Message received %s args %s" % ( msg, str(args)))
+
+        if msg == NS3WrapperMessage.SHUTDOWN:
+           stop = True
+   
+        reply = handle_message(ns3_wrapper, msg, args)
+
+        try:
+            send_reply(conn, reply)
+        except socket.error:
+            break
+
+if __name__ == '__main__':
+            
+    socket_name = get_options()
+
+    run_server(socket_name)
+