easiersnmp

easiersnmp is a wrapper around easysnmp to make it even easier to use. It also includes an alternative implementation of easysnmptable.

Python types

While I really like easysnmp, it returns instances of SNMPVariable instead of of the basic Python data types. In addition the actual value (SNMPVariable.value) will always be a string, even if the underlying SNMP type is numeric.

SNMP GET in easysnmp

import easysnmp
session = easysnmp.Session(hostname='localhost', community='public', version=2)
result = session.get('ifIndex.1')

# result is an instance of easysnmp.SNMPVariable
print(result.oid, result.oid_index, result.snmp_type, result.value)
# ifIndex 1 INTEGER 1

# The result.value is a string even though the snmp_type is INTEGER
print(type(result.value)
# str

easiersnmp changes this behaviour by converting SNMPVariable.value into the correct data type.

SNMP GET in easiersnmp

import easiersnmp
session = easiersnmp.Session(hostname='localhost', community='public', version=2)
result = session.get('ifIndex.1')

# result is an instance of easiersnmp.SNMPVariable
print(result.oid, result.oid_index, result.snmp_type, result.value)
# ifIndex 1 INTEGER 1

# The result.value is an integer matching the snmp_type
print(type(result.value)
# int

The table below shows how values are converted.

SNMPVariable.snmp_type	Python type
INTEGER32	int
INTEGER	int
UNSIGNED32	int
GAUGE	int
IPADDR	ipaddress.IPv4Address/ipaddress.IPv6Address
OCTETSTR	(read note below)
TICKS	datetime.timedelta
OPAQUE
OBJECTID
NETADDR	ipaddress.IPv4Address/ipaddress.IPv6Address
COUNTER64	int
NULL	None
BITS	int
UINTEGER	int

The OCTETSTR SNMP type is commonly used as a container for values that cannot be represented in any other SNMP type. It is impossible to know the correct interpretation of an OCTETSTR without parsing the relevant SNMP MIB.

Acknowledgements

I'd like to acknowledge the following projects.

• The EasySNMP project of which EasierSNMP is just a thin wrapper.
• The EasySNMP Table project which inspired my own implementation of a table() method.