add cpu usage check

checks/check_snmp_synology.py

@@ -292,6 +292,26 @@ class SNMPSynologyFirmwareResult(nagiosplugin.Result):
         return f'Firmware of {self.metric.value["model"]} (SN: {self.metric.value["sn"]}; Version: {self.metric.value["version"]}) is in status {status}!'
 
 
+#
+# Synology [DSM & DSM UC] Utilization % is the sum of user and system CPU usage
+# 
+class SNMPSynologyCPUResource(nagiosplugin.Resource):
+    def __init__(self, session) -> None:
+        self.session = session
+
+    def probe(self) -> list:
+        """check system temperature in °C
+        
+        Returns:
+            nagiosplugin.Metric: single metric element (return)
+        """
+        baseoid = '.1.3.6.1.4.1.6574.1'
+        oids = dict()
+        result = self.session.get(baseoid + '.7.1.0').value
+        return nagiosplugin.Metric(name='cpu', value=int(result), uom='%', context='cpu_scalar_context')
+
+    def __init__(self, session) -> None:
+        self.session = session
 
 
 
@@ -320,6 +340,7 @@ def parse_args() -> argparse.Namespace:
             'powersupply',
             'fans',
             'firmware',
+            'cpu',
         ],
         help='check mode to run')
 
@@ -390,6 +411,11 @@ def main():
             SNMPSynologyFirmwareContext(name='firmware_context'),
             nagiosplugin.Summary())
             check.name = "Firmware"
+        case 'cpu':
+            check = nagiosplugin.Check(SNMPSynologyCPUResource(session=session),
+            nagiosplugin.ScalarContext(name='cpu_scalar_context', warning=args.warning, critical=args.critical),
+            nagiosplugin.Summary())
+            check.name = "CPU Usage"
         case _:
             raise nagiosplugin.CheckError(f'Unknown check mode: {args.check_mode}')