Gufo SNMP Example: Multi Items Get Request

We have mastered the requesting of single item in our get example. But SNMP allows to query multiple keys in single request. Let's consider the example.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

Let's see the details.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

Import sys module to parse the CLI argument.

Warning

We use sys.argv only for demonstration purposes. Use argsparse or alternatives in real-world applications.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

Gufo SNMP is a typed library and it is good practice to place type hints in your code, so we import required type hints from Python's typing module.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

SnmpSession object holds all necessary API. We're using a synchronous version from gufo.snmp.sync_client.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

We define our main function and expect the following arguments:

• Address of the agent.
• SNMP community to authorize.
• List of OIDs to query.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

First, we need to create SnmpSession object which wraps the client's session. The SnmpSession may be used as an instance directly or operated as context manager using the with clause. When used as a context manager, the client automatically closes all connections on the exit of context, so its lifetime is defined explicitly.

SnmpSession constructor offers lots of configuration variables for fine-tuning. Refer to the SnmpSession reference for further details. In our example, we set the agent's address and SNMP community to the given values.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

We use SnmpSession.get_many() function to query multiple OIDs. See SnmpSession.get() reference for further details.

get_many() returns a dict, where keys are the requested OIDs, and values are the query results.

Note

get_many() ignores non-existent OIDs, so it is up to the application to check the resulting dict for missed keys.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

It is up to the application how to deal with the result. In our example we just print all the items.

import sys
from typing import List

from gufo.snmp.sync_client import SnmpSession


def main(addr: str, community: str, oids: List[str]) -> None:
    with SnmpSession(addr=addr, community=community) as session:
        r = session.get_many(oids)
        for k, v in r.items():
            print(f"{k}: {v}")


main(sys.argv[1], sys.argv[2], list(sys.argv[3:]))

Lets run our main() function and pass first command-line parameters as address, community and OIDs. We use the rest of command line as the list of OIDs to query.

Running

Let's check our script. Run example as:

$ python3 examples/sync/getmany.py 127.0.0.1 public 1.3.6.1.2.1.1.6.0 1.3.6.1.2.1.1.4.0
1.3.6.1.2.1.1.6.0: Gufo SNMP Test
1.3.6.1.2.1.1.4.0: test <me@example.com>