Projects using PySNMP

TwistedSNMP

Zenoss

Relevant projects

SNMPy YAPSNMP LibSMI Scotty software

import types
from pysnmp import session

class snmpget (session.session):
    """Fetch arbitrary variables from remote SNMP process
    """
    def __init__ (self, agent, community):
        """Explicitly call superclass's constructor as it gets
           overloaded by this class constructor and pass a few
           arguments alone.
        """
        session.session.__init__ (self, agent, community)

    def run (self, objids):
        """Query SNMP agent for one or more Object ID's. The objid
           argument should be a list of strings where each string
           represents a Object ID in dotted numbers notation
           (e.g. ['.1.3.6.1.4.1.307.3.2.1.1.1.4.1']).
        """   
        # Convert string type Object ID's into numeric representation
        numeric_objids = map (self.str2nums, objids)

        # BER encode SNMP Object ID's to query
        encoded_objids = map (self.encode_oid, numeric_objids)

        # Since we are going to _query_ SNMP agent for Object ID's
        # associated value, there will be no variable values passed to
        # SNMP agent.
        encoded_values = []
        
        # Build a complete SNMP message of type 'GETREQUEST', pass it a list
        # of BER encoded Object ID's to query and an empty list of values 
        # associated with these Object ID's (empty list as there is no point
        # to pass any variables values along the SNMP GET request)
        question = self.encode_request ('GETREQUEST', encoded_objids,\
                                        encoded_values)

        # Try to send SNMP message to SNMP agent and receive a response.
        answer = self.send_and_receive (question)

        # As we get a response from SNMP agent, try to disassemble SNMP reply
        # and extract two lists of BER encoded SNMP Object ID's and 
        # associated values).
        (encoded_objids, encoded_values) = self.decode_response (answer)

        # Decode BER encoded Object ID.
        objids = map (self.decode_value, encoded_objids)

        # Decode BER encoded values associated with Object ID's.
        values = map (self.decode_value, encoded_values)

        # Return a tuble of two lists holding Object ID's and associated
        # values extracted from SNMP agent reply.
        return (objids, values)

# Run the module if it's invoked for execution
if __name__ == '__main__':
    # The sys module is required for exit() function
    import sys

    # Make sure we have got enough args
    if len (sys.argv) < 4:
        # Report a usage error
        print 'Usage: %s   ' % sys.argv[0]

        # Incomplete command line arguments, exiting
        sys.exit (1)

    # Create an instance of snmpget class
    instance = snmpget (sys.argv[1], sys.argv[2])

    # Run snmpget against passed Object ID's and expect it to return a list
    # of Object ID's and corresponding values as reported by SNMP agent
    (objids, values) = instance.run (sys.argv[3:])

    # Convert two lists into a list of tuples for easier printing
    results = map (None, objids, values)

    # Just print them out
    for (objid, value) in results:
        response =  response + objid + ' ---> ' + repr(value)