Twisted support implemented

THANKS.txt

@@ -22,6 +22,7 @@ Ivan Zderadicka
 Randy Couey
 Brian Kyckelhahn
 Mark M Evans
+Filippo Giunchedi at Truelite Srl
 
 Thanks to Python Software Foundation for granting financial support 
 for the project.

pysnmp/carrier/twisted/base.py

@@ -0,0 +1,26 @@
+#
+#  Copyright (C) 2008 Truelite Srl <info@truelite.it>
+#  Author: Filippo Giunchedi <filippo@truelite.it>
+#
+#  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
+#
+#  Description: twisted DatagramProtocol UDP transport
+#
+
+class AbstractTwistedTransport:
+    """Base Twisted Transport, to be used with TwistedDispatcher"""
+    def __init__(self):
+        self._writeQ = []
+
+    # AbstractTwistedTransport API
+    
+    def registerCbFun(self, cbFun):
+        self._cbFun = cbFun
+
+    def unregisterCbFun(self):
+        self._cbFun = None
+
+    def closeTransport(self):
+        self.unregisterCbFun()

pysnmp/carrier/twisted/dgram/base.py

@@ -0,0 +1,44 @@
+"""Implements twisted-based generic DGRAM transport"""
+from time import time
+from twisted.internet.protocol import DatagramProtocol
+from twisted.internet import reactor
+from pysnmp.carrier.twisted.base import AbstractTwistedTransport
+from pysnmp.carrier import error
+from pysnmp import debug
+
+class DgramTwistedTransport(DatagramProtocol, AbstractTwistedTransport):
+    """Base Twisted datagram Transport, to be used with TwistedDispatcher"""
+
+    # Twisted Datagram API
+    
+    def datagramReceived(self, datagram, address):
+        if self._cbFun is None:
+            raise error.CarrierError('Unable to call cbFun')
+        else:
+            # Callback fun is called through callLater() in attempt
+            # to make Twisted timed calls work under high load.
+            reactor.callLater(0, self._cbFun, self, address, datagram)
+
+    def startProtocol(self):
+        debug.logger & debug.flagIO and debug.logger('startProtocol: invoked')
+        while self._writeQ:
+            outgoingMessage, transportAddress = self._writeQ.pop(0)
+            debug.logger & debug.flagIO and debug.logger('startProtocol: transportAddress %s outgoingMessage %s' % (transportAddress, repr(outgoingMessage)))
+            try:
+                self.transport.write(outgoingMessage, transportAddress)
+            except Exception, why:
+                raise error.CarrierError('Twisted exception: %s' % (why,))
+
+    def stopProtocol(self):
+        debug.logger & debug.flagIO and debug.logger('stopProtocol: invoked')
+        self.closeTransport()
+
+    def sendMessage(self, outgoingMessage, transportAddress):
+        debug.logger & debug.flagIO and debug.logger('startProtocol: %s transportAddress %s outgoingMessage %s' % ((self.transport is None and "queuing" or "sending"), transportAddress, repr(outgoingMessage)))        
+        if self.transport is None:
+            self._writeQ.append((outgoingMessage, transportAddress))
+        else:
+            try:
+                self.transport.write(outgoingMessage, transportAddress)
+            except Exception, why:
+                raise error.CarrierError('Twisted exception: %s' % (why,))

pysnmp/carrier/twisted/dgram/udp.py

@@ -0,0 +1,25 @@
+"""Implements twisted-based UDP transport"""
+from twisted.internet import reactor
+from pysnmp.carrier.twisted.dgram.base import DgramTwistedTransport
+from pysnmp.carrier import error
+
+domainName = snmpUDPDomain = (1, 3, 6, 1, 6, 1, 1)
+
+class UdpTwistedTransport(DgramTwistedTransport):
+    # AbstractTwistedTransport API
+    
+    def openClientMode(self, iface=''):
+        try:
+            self._lport = reactor.listenUDP(0, self, iface)
+        except Exception, why:
+            raise error.CarrierError(why)
+        return self
+
+    def openServerMode(self, iface=None):
+        try:
+            self._lport = reactor.listenUDP(iface[1], self, iface[0])
+        except Exception, why:
+            raise error.CarrierError(why)
+        return self
+
+UdpTransport = UdpTwistedTransport

pysnmp/carrier/twisted/dgram/unix.py

@@ -0,0 +1,26 @@
+"""Implements twisted-based UNIX domain socket transport"""
+from twisted.internet import reactor
+from pysnmp.carrier.twisted.dgram.base import DgramTwistedTransport
+from pysnmp.carrier import error
+
+domainName = snmpLocalDomain = (1, 3, 6, 1, 2, 1, 100, 1, 13)
+
+class UnixTwistedTransport(DgramTwistedTransport):
+    # AbstractTwistedTransport API
+    
+    def openClientMode(self, iface=''):
+        try:
+            self._lport = reactor.connectUNIXDatagram(iface, self)
+        except Exception, why:
+            raise error.CarrierError(why)
+        return self
+
+    def openServerMode(self, iface=None):
+        try:
+            self._lport = reactor.listenUNIXDatagram(iface, self)
+        except Exception, why:
+            raise error.CarrierError(why)
+        
+        return self
+
+UnixTransport = UnixTwistedTransport

pysnmp/carrier/twisted/dispatch.py

@@ -0,0 +1,53 @@
+#
+#  Copyright (C) 2008 Truelite Srl <info@truelite.it>
+#  Author: Filippo Giunchedi <filippo@truelite.it>
+#
+#  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
+#
+# Description: Transport dispatcher based on twisted.internet.reactor
+#
+from time import time
+from twisted.internet import reactor, task
+from pysnmp.carrier.base import AbstractTransportDispatcher
+from pysnmp.carrier import error
+
+class TwistedDispatcher(AbstractTransportDispatcher):
+    """TransportDispatcher based on twisted.internet.reactor"""
+    def __init__(self, *args, **kwargs):
+        AbstractTransportDispatcher.__init__(self)
+        self.__transportCount = 0
+        self.timeout = kwargs.get('timeout', 1.0)
+        self.loopingcall = task.LoopingCall(self.handleTimeout)
+
+    def handleTimeout(self):
+        self.handleTimerTick(time())
+
+    def runDispatcher(self, timeout=0.0):
+        if not reactor.running:
+            try:
+                reactor.run()
+            except Exception, why:
+                raise error.CarrierError(why)
+
+    # jobstarted/jobfinished might be okay as-is
+
+    def registerTransport(self, tDomain, transport):
+        if not self.loopingcall.running and self.timeout > 0:
+            self.loopingcall.start(self.timeout, now = False)
+        AbstractTransportDispatcher.registerTransport(
+            self, tDomain, transport
+            )
+        self.__transportCount = self.__transportCount + 1
+
+    def unregisterTransport(self, tDomain):
+        t = AbstractTransportDispatcher.getTransport(self, tDomain)
+        if t is not None:
+            AbstractTransportDispatcher.unregisterTransport(self, tDomain)
+            t.closeTransport()
+            self.__transportCount = self.__transportCount - 1
+
+        # The last transport has been removed, stop the timeout
+        if self.__transportCount > 0 and self.loopingcall.running:
+            self.loopingcall.stop()

setup.py

@@ -15,9 +15,12 @@ setup(name="pysnmp",
                    'pysnmp.v4.carrier',
                    'pysnmp.v4.carrier.asynsock',
                    'pysnmp.v4.carrier.asynsock.dgram',
+                   'pysnmp.v4.carrier.twisted',
+                   'pysnmp.v4.carrier.twisted.dgram',                   
                    'pysnmp.v4.entity',
                    'pysnmp.v4.entity.rfc3413',
                    'pysnmp.v4.entity.rfc3413.oneliner',
+                   'pysnmp.v4.entity.rfc3413.twisted',
                    'pysnmp.v4.proto',
                    'pysnmp.v4.proto.mpmod',
                    'pysnmp.v4.proto.secmod',