def get_single_oid(snmp_config,
oid,
check_plugin_name=None,
do_snmp_scan=True):
# type: (SNMPHostConfig, str, Optional[str], bool) -> Optional[DecodedString]
# The OID can end with ".*". In that case we do a snmpgetnext and try to
# find an OID with the prefix in question. The *cache* is working including
# the X, however.
if oid[0] != '.':
if cmk.utils.debug.enabled():
raise MKGeneralException(
"OID definition '%s' does not begin with a '.'" % oid)
oid = '.' + oid
# TODO: Use generic cache mechanism
if snmp_cache.is_in_single_oid_cache(oid):
console.vverbose(" Using cached OID %s: " % oid)
cached_value = snmp_cache.get_oid_from_single_oid_cache(oid)
console.vverbose("%s%s%r%s\n" %
(tty.bold, tty.green, cached_value, tty.normal))
return cached_value
# get_single_oid() can only return a single value. When SNMPv3 is used with multiple
# SNMP contexts, all contextes will be queried until the first answer is received.
if check_plugin_name is not None and snmp_config.is_snmpv3_host:
snmp_contexts = _snmpv3_contexts_of(snmp_config, check_plugin_name)
else:
snmp_contexts = [None]
console.vverbose(" Getting OID %s: " % oid)
for context_name in snmp_contexts:
try:
value = SNMPBackendFactory.get(snmp_config,
use_cache=_enforce_stored_walks,
oid=oid,
context_name=context_name)
if value is not None:
break # Use first received answer in case of multiple contextes
except Exception:
if cmk.utils.debug.enabled():
raise
value = None
if value is not None:
console.vverbose("%s%s%r%s\n" %
(tty.bold, tty.green, value, tty.normal))
else:
console.vverbose("failed.\n")
if value is not None:
decoded_value = convert_to_unicode(
value, encoding=snmp_config.character_encoding
) # type: Optional[DecodedString]
else:
decoded_value = value
snmp_cache.set_single_oid_cache(oid, decoded_value)
return decoded_value
def test_get_single_oid_cache(snmp_config):
oid = ".1.3.6.1.2.1.1.1.0"
expected_value = "Linux zeus 4.8.6.5-smp #2 SMP Sun Nov 13 14:58:11 CDT 2016 i686"
assert snmp.get_single_oid(snmp_config, oid) == expected_value
assert snmp_cache.is_in_single_oid_cache(oid)
cached_oid = snmp_cache.get_oid_from_single_oid_cache(oid)
assert cached_oid == expected_value
assert isinstance(cached_oid, str)