text: """
  Listen for notifications at IPv4 & IPv6 interfaces
  ++++++++++++++++++++++++++++++++++++++++++++++++++
  
  Receive SNMP TRAP messages with the following options:
  
  * SNMPv1/SNMPv2c
  * with SNMP community "public"
  * over IPv4/UDP, listening at 127.0.0.1:162
  * over IPv6/UDP, listening at [::1]:162
  * print received data on stdout
  
  Either of the following Net-SNMP commands will send notifications to this 
  receiver:
  
  | $ snmptrap -v1 -c public 127.0.0.1 1.3.6.1.4.1.20408.4.1.1.2 127.0.0.1 1 1 123 1.3.6.1.2.1.1.1.0 s test
  | $ snmptrap -v2c -c public udp6:[::1] 123 1.3.6.1.6.3.1.1.5.1 1.3.6.1.2.1.1.5.0 s test
  
  Notification Receiver below uses two different transports for communication 
  with Notification Originators - UDP over IPv4 and UDP over IPv6.
  
  """#
  from pysnmp.carrier.asyncore.dispatch import AsyncoreDispatcher
  from pysnmp.carrier.asyncore.dgram import udp, udp6
  from pyasn1.codec.ber import decoder
  from pysnmp.proto import api
  
  
  # noinspection PyUnusedLocal
  def cbFun(transportDispatcher, transportDomain, transportAddress, wholeMsg):
  
      while wholeMsg:
          msgVer = int(api.decodeMessageVersion(wholeMsg))
          if msgVer in api.PROTOCOL_MODULES:
              pMod = api.PROTOCOL_MODULES[msgVer]
  
          else:
              print('Unsupported SNMP version %s' % msgVer)
              return
  
          reqMsg, wholeMsg = decoder.decode(
              wholeMsg, asn1Spec=pMod.Message(),
          )
  
          print('Notification message from %s:%s: ' % (transportDomain,
                                                       transportAddress))
  
          reqPDU = pMod.apiMessage.getPDU(reqMsg)
          if reqPDU.isSameTypeWith(pMod.TrapPDU()):
              if msgVer == api.SNMP_VERSION_1:
                  print('Enterprise: %s' % (pMod.apiTrapPDU.getEnterprise(reqPDU).prettyPrint()))
                  print('Agent Address: %s' % (pMod.apiTrapPDU.getAgentAddr(reqPDU).prettyPrint()))
                  print('Generic Trap: %s' % (pMod.apiTrapPDU.getGenericTrap(reqPDU).prettyPrint()))
                  print('Specific Trap: %s' % (pMod.apiTrapPDU.getSpecificTrap(reqPDU).prettyPrint()))
                  print('Uptime: %s' % (pMod.apiTrapPDU.getTimeStamp(reqPDU).prettyPrint()))
                  varBinds = pMod.apiTrapPDU.getVarBinds(reqPDU)
  
              else:
                  varBinds = pMod.apiPDU.getVarBinds(reqPDU)
  
              print('Var-binds:')
  
              for oid, val in varBinds:
                  print('%s = %s' % (oid.prettyPrint(), val.prettyPrint()))
  
      return wholeMsg
  
  
  transportDispatcher = AsyncoreDispatcher()
  
  transportDispatcher.registerRecvCbFun(cbFun)
  
  # UDP/IPv4
  transportDispatcher.registerTransport(
      udp.DOMAIN_NAME, udp.UdpSocketTransport().openServerMode(('localhost', 162))
  )
  
  # UDP/IPv6
  transportDispatcher.registerTransport(
      udp6.DOMAIN_NAME, udp6.Udp6SocketTransport().openServerMode(('::1', 162))
  )
  
  transportDispatcher.jobStarted(1)
  
  try:
      # Dispatcher will never finish as job#1 never reaches zero
      transportDispatcher.runDispatcher()
  
  finally:
      transportDispatcher.closeDispatcher()
  