Handle FM APIExceptions

Support for alarm overrides was recently committed. However,
the default override for alarm severity is set to 'unknown'.
If this default is applied on newly raised alarms, FM rejects
the alarms since an 'unknown' severity type is not supported.

In addition, added try-except blocks around the FM API calls.
APIException was being raised by FM, which was unhandled
previously.

Test Plan:
PASS: Verify that non-overridden alarm severity can raise
      alarm without any errors from FM.
PASS: Verify that any exception raised by FM is handled.

Story: 2008946
Task: 42852

Signed-off-by: Sabeel Ansari <Sabeel.Ansari@windriver.com>
Change-Id: Ife732114cdda8e10ffb0bc785c52399b13d0f8af

sysinv/sysinv/sysinv/sysinv/cert_alarm/fm.py

@@ -129,8 +129,10 @@ class FaultApiMgr(object):
         # Check for annotation overrides
         if cert_name in utils.CERT_SNAPSHOT:
             snapshot = utils.CERT_SNAPSHOT[cert_name]
-            alarm_severity = snapshot.get(constants.CERT_ALARM_ANNOTATION_ALARM_SEVERITY,
-                                          alarm_severity)
+            override = snapshot.get(constants.CERT_ALARM_ANNOTATION_ALARM_SEVERITY,
+                                    alarm_severity)
+            if override != "unknown":  # Cannot have "unknown" for fault severity
+                alarm_severity = override
 
         return alarm_severity
 
@@ -148,44 +150,51 @@ class FaultApiMgr(object):
                 else fm_constants.FM_ALARM_ID_CERT_EXPIRING_SOON
         entity_inst_id = self.get_entity_instance_id(cert_name)
 
-        if state == fm_constants.FM_ALARM_STATE_SET:
-            # Raise alarm only if alarm does not already exist
-            if not self.fm_api.get_fault(alrm_id, entity_inst_id):
-                # Check for annotation override
-                if cert_name in utils.CERT_SNAPSHOT:
-                    snapshot = utils.CERT_SNAPSHOT[cert_name]
-                    if snapshot.get(constants.CERT_ALARM_ANNOTATION_ALARM,
-                                    constants.CERT_ALARM_DEFAULT_ANNOTATION_ALARM) == 'disabled':
-                        LOG.info('Found annotation override, disabling alarm. Suppressing %s' %
-                                 cert_name)
-                        return
+        try:
+            if state == fm_constants.FM_ALARM_STATE_SET:
+                # Raise alarm only if alarm does not already exist
+                if not self.fm_api.get_fault(alrm_id, entity_inst_id):
+                    # Check for annotation override
+                    if cert_name in utils.CERT_SNAPSHOT:
+                        snapshot = utils.CERT_SNAPSHOT[cert_name]
+                        if snapshot.get(constants.CERT_ALARM_ANNOTATION_ALARM,
+                                        constants.CERT_ALARM_DEFAULT_ANNOTATION_ALARM) == 'disabled':
+                            LOG.info('Found annotation override, disabling alarm. Suppressing %s' %
+                                    cert_name)
+                            return
 
-                fault = fm_api.Fault(
-                        alarm_id=alrm_id,
-                        alarm_state=state,
-                        entity_type_id=fm_constants.FM_ENTITY_TYPE_CERTIFICATE,
-                        entity_instance_id=entity_inst_id,
-                        severity=self.get_severity(cert_name, expired_flag),
-                        reason_text=self.get_reason_text(cert_name, expired_flag),
-                        alarm_type=fm_constants.FM_ALARM_TYPE_9,  # security-service
-                        probable_cause=fm_constants.ALARM_PROBABLE_CAUSE_77,  # certificate-expiration
-                        proposed_repair_action="Renew certificate for entity identified",
-                        suppression=False,
-                        service_affecting=False)
+                    fault = fm_api.Fault(
+                            alarm_id=alrm_id,
+                            alarm_state=state,
+                            entity_type_id=fm_constants.FM_ENTITY_TYPE_CERTIFICATE,
+                            entity_instance_id=entity_inst_id,
+                            severity=self.get_severity(cert_name, expired_flag),
+                            reason_text=self.get_reason_text(cert_name, expired_flag),
+                            alarm_type=fm_constants.FM_ALARM_TYPE_9,
+                            probable_cause=fm_constants.ALARM_PROBABLE_CAUSE_77,
+                            proposed_repair_action="Renew certificate for entity identified",
+                            suppression=False,
+                            service_affecting=False)
 
-                LOG.info('Setting fault for cert_name=%s, expired_flag=%s, state=%s' %
-                        (cert_name, expired_flag, state))
-                self.fm_api.set_fault(fault)
-        else:
-            if self.fm_api.get_fault(alrm_id, entity_inst_id):
-                LOG.info('Setting fault for cert_name=%s, expired_flag=%s, state=%s' %
-                        (cert_name, expired_flag, state))
-                self.fm_api.clear_fault(alrm_id, entity_inst_id)
+                    LOG.info('Setting fault for cert_name=%s, expired_flag=%s, state=%s' %
+                            (cert_name, expired_flag, state))
+                    self.fm_api.set_fault(fault)
+            else:
+                if self.fm_api.get_fault(alrm_id, entity_inst_id):
+                    LOG.info('Setting fault for cert_name=%s, expired_flag=%s, state=%s' %
+                            (cert_name, expired_flag, state))
+                    self.fm_api.clear_fault(alrm_id, entity_inst_id)
+        except Exception as e:
+            LOG.warn(e)
 
     def get_faults(self, expired_flag):
         alrm_id = fm_constants.FM_ALARM_ID_CERT_EXPIRED if expired_flag \
                 else fm_constants.FM_ALARM_ID_CERT_EXPIRING_SOON
-        alarms = self.fm_api.get_faults_by_id(alrm_id)
+        alarms = None
+        try:
+            alarms = self.fm_api.get_faults_by_id(alrm_id)
+        except Exception as e:
+            LOG.warn(e)
         return alarms
 
     def collect_all_cert_alarms(self):