add fan check

checks/check_snmp_synology.py

@@ -8,7 +8,7 @@
     - https://easysnmp.readthedocs.io/en/latest/session_api.html
 """
 
-__version__     = '0.3.0'
+__version__     = '0.4.0'
 __author__      = 'anima'
 
 # imports
@@ -186,6 +186,62 @@ class SNMPSynologyPowerSupplyContext(nagiosplugin.Context):
         return self.result_cls(nagiosplugin.Unknown, "unknown", metric)
 
 
+#
+# Synology [DSM & DSM UC] Returns error if system fan fails
+#
+class SNMPSynologyFansResource(nagiosplugin.Resource):
+    def __init__(self, session) -> None:
+        self.session = session
+
+    def probe(self) -> list:
+        """check fans status (normal or failed)
+        
+        Returns:
+            nagiosplugin.Metric: single metric element (return)
+        """
+        baseoid = '.1.3.6.1.4.1.6574.1'
+        fans = dict()
+        fans['system'] = '.4.1.0'
+        fans['cpu'] = '.4.2.0'
+
+        for fan, oid in fans.items():
+            result = self.session.get(baseoid + oid).value
+            yield nagiosplugin.Metric(name=fan, value=result, context='fan_context')
+
+
+class SNMPSynologyFansResult(nagiosplugin.Result):
+    def __str__(self):
+        if self.metric.value == '1': status = 'normal'
+        else: status = 'failed'
+        return f'{self.metric.name} fan is in status {status}!'
+
+
+class SNMPSynologyFansContext(nagiosplugin.Context):
+    def __init__(self, name):
+        super().__init__(name, fmt_metric='{name} is', result_cls=SNMPSynologyFansResult)
+
+    def evaluate(self, metric, resource):
+        if metric.value == '2':
+            return self.result_cls(nagiosplugin.Critical, "critical", metric)
+        elif metric.value == '1':
+            return self.result_cls(nagiosplugin.Ok, "ok", metric)
+        return self.result_cls(nagiosplugin.Unknown, "unknown", metric)
+
+
+class SNMPSynologyFansSummary(nagiosplugin.Summary):
+    def verbose(self, results):
+        result_str = ''
+        for result in results:
+            result_str += f'{str(result)}\n'
+        return result_str
+
+    def ok(self, results):
+        return
+
+    def problem(self, results):
+        return
+
+
 #
 # Arguments
 #
@@ -209,6 +265,7 @@ def parse_args() -> argparse.Namespace:
             'system',
             'systemp',
             'powersupply',
+            'fans',
         ],
         help='check mode to run')
 
@@ -269,6 +326,11 @@ def main():
             SNMPSynologyPowerSupplyContext(name='powersupply_context'),
             nagiosplugin.Summary())
             check.name = "Power Supply Status"
+        case 'fans':
+            check = nagiosplugin.Check(SNMPSynologyFansResource(session=session),
+            SNMPSynologyFansContext(name='fan_context'),
+            SNMPSynologyFansSummary())
+            check.name = "Fans Status"
         case _:
             raise nagiosplugin.CheckError(f'Unknown check mode: {args.check_mode}')