validating home az value (#1902)

validate home az value
change default PopulateHomeAzCacheRetryIntervalSecs value from 15 to 30

Author: ZetaoZhuang

cns/configuration/configuration.go

@@ -189,8 +189,8 @@ func SetCNSConfigDefaults(config *CNSConfig) {
 		config.SyncHostNCTimeoutMs = 500 //nolint:gomnd // default times
 	}
 	if config.PopulateHomeAzCacheRetryIntervalSecs == 0 {
-		// set the default PopulateHomeAzCache retry interval to 15 seconds
-		config.PopulateHomeAzCacheRetryIntervalSecs = 15
+		// set the default PopulateHomeAzCache retry interval to 30 seconds
+		config.PopulateHomeAzCacheRetryIntervalSecs = 30
 	}
 	if config.WireserverIP == "" {
 		config.WireserverIP = "168.63.129.16"

cns/configuration/configuration_test.go

@@ -206,7 +206,7 @@ func TestSetCNSConfigDefaults(t *testing.T) {
 				KeyVaultSettings: KeyVaultSettings{
 					RefreshIntervalInHrs: 12,
 				},
-				PopulateHomeAzCacheRetryIntervalSecs: 15,
+				PopulateHomeAzCacheRetryIntervalSecs: 30,
 				WireserverIP:                         "168.63.129.16",
 			},
 		},

cns/restserver/homeazmonitor.go

@@ -139,6 +139,13 @@ func (h *HomeAzMonitor) Populate(ctx context.Context) {
 		return
 	}
 
+	// validate home az value, HomeAz is a uint, so it's value >=0
+	if azResponse.HomeAz == 0 {
+		returnMessage := fmt.Sprintf("[HomeAzMonitor] invalid home az value from nmagent: %d", azResponse.HomeAz)
+		returnCode := types.UnexpectedError
+		h.update(returnCode, returnMessage, cns.HomeAzResponse{IsSupported: true})
+		return
+	}
 	h.update(types.Success, "Get Home Az succeeded", cns.HomeAzResponse{IsSupported: true, HomeAz: azResponse.HomeAz})
 }
 

cns/restserver/homeazmonitor_test.go

@@ -47,6 +47,19 @@ func TestHomeAzMonitor(t *testing.T) {
 			cns.HomeAzResponse{},
 			false,
 		},
+		{
+			"api supported but home az value is not valid",
+			&fakes.NMAgentClientFake{
+				SupportedAPIsF: func(ctx context.Context) ([]string, error) {
+					return []string{GetHomeAzAPIName}, nil
+				},
+				GetHomeAzF: func(ctx context.Context) (nmagent.AzResponse, error) {
+					return nmagent.AzResponse{HomeAz: 0}, nil
+				},
+			},
+			cns.HomeAzResponse{IsSupported: true},
+			true,
+		},
 		{
 			"api supported but got unexpected errors",
 			&fakes.NMAgentClientFake{