Merge pull request #5 from slawr/rebase-iotdb-config-support

Apache IoTDB: add runtime configuration file support for connector

server/vissv2server/iotdb-config.json

@@ -0,0 +1,8 @@
+{
+	"host": "iotdb-service",
+	"port": "6667",
+	"username": "root",
+	"password": "root",
+	"queryPrefixPath": "root.test2.dev1",
+	"queryTimeout(ms)": 5000
+}

server/vissv2server/serviceMgr/serviceMgr.go

@@ -79,16 +79,33 @@ var historySupport bool
 
 // Apache IoTDB
 var IoTDBsession client.Session
-var IoTDbPrefixPath string = "root.test2.dev1" // DB prefix used for get/set
-var IoTDbTimeout int64 = 3000
-var IoTDBconfig = &client.Config{
-	//	Host:     "127.0.0.1",
-	Host:     "iotdb-service",
+var IoTDBClientConfig = &client.Config {
+	Host:     "127.0.0.1",
 	Port:     "6667",
 	UserName: "root",
 	Password: "root",
 }
 
+type IoTDBConfiguration struct {
+	Host string		`json:"host"`
+	Port string		`json:"port"`
+	UserName string `json:"username"`
+	Password string `json:"password"`
+	PrefixPath string `json:"queryPrefixPath"`
+	Timeout int64	`json:"queryTimeout(ms)"`
+}
+
+// Default IoTDB connector configuration
+var IoTDBConfig = IoTDBConfiguration {
+	"127.0.0.1",
+	"6667",
+	"root",
+	"root",
+	"root.test2.dev1",
+	5000,
+}
+
+
 var dummyValue int // dummy value returned when DB configured to none. Counts from 0 to 999, wrap around, updated every 47 msec
 
 func initDataServer(serviceMgrChan chan string, clientChannel chan string, backendChannel chan string) {
@@ -495,12 +512,12 @@ func getVehicleData(path string) string { // returns {"value":"Y", "ts":"Z"}
 	case "apache-iotdb":
 		var (
 			// Back-quote the VSS node for the DB query, e.g. `Vehicle.CurrentLocation.Longitude`
-			selectLastSQL = fmt.Sprintf("select last `%v` from %v", path, IoTDbPrefixPath)
-			value         = ""
-			ts            = ""
+			selectLastSQL = fmt.Sprintf("select last `%v` from %v", path, IoTDBConfig.PrefixPath)
+			value = ""
+			ts = ""
 		)
-		//		utils.Info.Printf("IoTDB: query using: %v", selectLastSQL)
-		sessionDataSet, err := IoTDBsession.ExecuteQueryStatement(selectLastSQL, &IoTDbTimeout)
+//		utils.Info.Printf("IoTDB: query using: %v", selectLastSQL)
+		sessionDataSet, err := IoTDBsession.ExecuteQueryStatement(selectLastSQL, &IoTDBConfig.Timeout)
 		if err == nil {
 			var success bool
 			success, err = sessionDataSet.Next()
@@ -573,8 +590,8 @@ func setVehicleData(path string, value string) string {
 		IoTDBts := time.Now().UTC().UnixNano() / 1000000
 
 		// IoTDB will automatically convert the value string to the native data type in the timeseries schema for basic types
-		//		utils.Info.Printf("IoTDB: DB insert with prefixPath: %v vssKey: %v, vssValue: %v, ts: %v", IoTDbPrefixPath, vssKey, vssValue, IoTDBts)
-		if status, err := IoTDBsession.InsertStringRecord(IoTDbPrefixPath, vssKey, vssValue, IoTDBts); err != nil {
+//		utils.Info.Printf("IoTDB: DB insert with prefixPath: %v vssKey: %v, vssValue: %v, ts: %v", IoTDBConfig.PrefixPath, vssKey, vssValue, IoTDBts)
+		if status, err := IoTDBsession.InsertStringRecord(IoTDBConfig.PrefixPath, vssKey, vssValue, IoTDBts); err != nil {
 			utils.Error.Printf("IoTDB: DB insert using InsertStringRecord failed with: %v", err)
 			return ""
 		} else {
@@ -983,10 +1000,34 @@ func ServiceMgrInit(mgrId int, serviceMgrChan chan string, stateStorageType stri
 		}
 		utils.Info.Printf("Redis state storage initialised.")
 	case "apache-iotdb":
-		utils.Info.Printf("IoTDB: creating new session with host:%v port:%v user:%v pass:%v", IoTDBconfig.Host, IoTDBconfig.Port, IoTDBconfig.UserName, IoTDBconfig.Password)
-		IoTDBsession = client.NewSession(IoTDBconfig)
+		// Read configuration from file if present else use defaults
+		IoTDBConfigFilename := "iotdb-config.json"
+		utils.Info.Printf("IoTDB: Default configuration before config file read = %+v", IoTDBConfig)
+		data, err := os.ReadFile(IoTDBConfigFilename)
+		if err != nil {
+			utils.Error.Printf("IoTDB: Failed to read configuration from %v with error = %+v", IoTDBConfigFilename, err)
+		} else {
+			var IoTDBJSONConfig IoTDBConfiguration
+			err = json.Unmarshal(data, &IoTDBJSONConfig)
+			if err != nil {
+				utils.Error.Printf("IoTDB: Failed to unmarshal the JSON config data from %v with error = %+v", IoTDBConfigFilename, err)
+			} else {
+				utils.Info.Printf("IoTDB: Configuration read from config file %v = %+v", IoTDBConfigFilename, IoTDBJSONConfig)
+				// Success. Copy config read from the file.
+				IoTDBConfig = IoTDBJSONConfig
+			}
+		}
+
+		IoTDBClientConfig.Host = IoTDBConfig.Host
+		IoTDBClientConfig.Port = IoTDBConfig.Port
+		IoTDBClientConfig.UserName = IoTDBConfig.UserName
+		IoTDBClientConfig.Password = IoTDBConfig.Password
+
+		// Create new client session with IoTDB server
+		utils.Info.Printf("IoTDB: Creating new session with client config = %+v", *IoTDBClientConfig)
+		IoTDBsession = client.NewSession(IoTDBClientConfig)
 		if err := IoTDBsession.Open(false, 0); err != nil {
-			utils.Error.Printf("IoTDB: Failed to open session with error=%s", err)
+			utils.Error.Printf("IoTDB: Failed to open server session with error=%s", err)
 			os.Exit(1)
 		}
 		defer IoTDBsession.Close()