Add TM monitoring.json validity check for safety

traffic_monitor/towrap/towrap.go

@@ -244,6 +244,43 @@ func (s *TrafficOpsSessionThreadsafe) CRConfigValid(crc *tc.CRConfig, cdn string
 	return nil
 }
 
+func MonitorConfigValid(cfg *tc.TrafficMonitorConfigMap) error {
+	if cfg == nil {
+		return errors.New("MonitorConfig is nil")
+	}
+	if len(cfg.TrafficServer) == 0 {
+		return errors.New("MonitorConfig.TrafficServer empty (is the monitoring.json an empty object?)")
+	}
+	if len(cfg.CacheGroup) == 0 {
+		return errors.New("MonitorConfig.CacheGroup empty")
+	}
+	if len(cfg.TrafficMonitor) == 0 {
+		return errors.New("MonitorConfig.TrafficMonitor empty")
+	}
+	// TODO uncomment this, when TO is fixed to include DeliveryServices.
+	// See https://github.com/apache/trafficcontrol/issues/3528
+	// if len(cfg.DeliveryService) == 0 {
+	// 	return errors.New("MonitorConfig.DeliveryService empty")
+	// }
+	if len(cfg.Profile) == 0 {
+		return errors.New("MonitorConfig.Profile empty")
+	}
+
+	if intervalI, ok := cfg.Config["peers.polling.interval"]; !ok {
+		return errors.New(`MonitorConfig.Config["peers.polling.interval"] missing, peers.polling.interval parameter required`)
+	} else if _, ok := intervalI.(float64); !ok {
+		return fmt.Errorf(`MonitorConfig.Config["peers.polling.interval"] '%v' not a number, parameter peers.polling.interval must be a number`, intervalI)
+	}
+
+	if intervalI, ok := cfg.Config["health.polling.interval"]; !ok {
+		return errors.New(`MonitorConfig.Config["health.polling.interval"] missing, health.polling.interval parameter required`)
+	} else if _, ok := intervalI.(float64); !ok {
+		return fmt.Errorf(`MonitorConfig.Config["health.polling.interval"] '%v' not a number, parameter health.polling.interval must be a number`, intervalI)
+	}
+
+	return nil
+}
+
 // CRConfigRaw returns the CRConfig from the Traffic Ops. This is safe for multiple goroutines.
 func (s TrafficOpsSessionThreadsafe) CRConfigRaw(cdn string) ([]byte, error) {
 
@@ -318,10 +355,15 @@ func (s TrafficOpsSessionThreadsafe) trafficMonitorConfigMapRaw(cdn string) (*tc
 	}
 
 	configMap, _, err := ss.GetTrafficMonitorConfigMap(cdn)
+
+	if err == nil {
+		err = MonitorConfigValid(configMap)
+	}
+
 	if err != nil {
 		// Default error case, no backup file exists
 		if !s.BackupFileExists() {
-			return configMap, err
+			return nil, err
 		}
 
 		b, err := ioutil.ReadFile(s.TMConfigBackupFile)
@@ -342,6 +384,7 @@ func (s TrafficOpsSessionThreadsafe) trafficMonitorConfigMapRaw(cdn string) (*tc
 	if err == nil {
 		ioutil.WriteFile(s.TMConfigBackupFile, data, 0644)
 	}
+
 	return configMap, err
 }
 

traffic_monitor/towrap/towrap_test.go

@@ -0,0 +1,52 @@
+package towrap
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import (
+	"testing"
+
+	"github.com/apache/trafficcontrol/lib/go-tc"
+)
+
+func TestMonitorConfigValid(t *testing.T) {
+	mc := (*tc.TrafficMonitorConfigMap)(nil)
+	if MonitorConfigValid(mc) == nil {
+		t.Errorf("MonitorCopnfigValid(nil) expected: error, actual: nil")
+	}
+	mc = &tc.TrafficMonitorConfigMap{}
+	if MonitorConfigValid(mc) == nil {
+		t.Errorf("MonitorConfigValid({}) expected: error, actual: nil")
+	}
+
+	validMC := &tc.TrafficMonitorConfigMap{
+		TrafficServer:   map[string]tc.TrafficServer{"a": {}},
+		CacheGroup:      map[string]tc.TMCacheGroup{"a": {}},
+		TrafficMonitor:  map[string]tc.TrafficMonitor{"a": {}},
+		DeliveryService: map[string]tc.TMDeliveryService{"a": {}},
+		Profile:         map[string]tc.TMProfile{"a": {}},
+		Config: map[string]interface{}{
+			"peers.polling.interval":  42.0,
+			"health.polling.interval": 24.0,
+		},
+	}
+	if err := MonitorConfigValid(validMC); err != nil {
+		t.Errorf("MonitorConfigValid(%++v) expected: nil, actual: %+v", validMC, err)
+	}
+}