Add auto reconnect function.

main.go

@@ -40,7 +40,7 @@ type Payload struct {
 var db *sql.DB
 
 func main() {
-	// Load environment variables from .env file if it exists
+	// // Load environment variables from .env file if it exists
 	// err := godotenv.Load()
 	// if err != nil {
 	// 	log.Println("Error loading .env file:", err)
@@ -48,52 +48,17 @@ func main() {
 
 	// Connect to PostgreSQL
 	pgConnStr := os.Getenv("PG_DB")
-	var err error
+	if err := connectToPostgreSQL(pgConnStr); err != nil {
-	db, err = sql.Open("postgres", pgConnStr)
+		log.Fatal("Error connecting to PostgreSQL:", err)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer db.Close()
-
-	// Enable TimescaleDB
-	// _, err = db.Exec(`
-	// 	CREATE EXTENSION IF NOT EXISTS timescaledb;
-	// `)
-	if err != nil {
-		log.Fatal("Error creating TimescaleDB extension:", err)
 	}
 
-	// Create table if not exists
+	// pgConnStr := os.Getenv("PG_DB")
-	_, err = db.Exec(`
+	// var err error
-		CREATE TABLE IF NOT EXISTS p1 (
+	// db, err = sql.Open("postgres", pgConnStr)
-			timestamp TIMESTAMPTZ,
+	// if err != nil {
-			delivered_tariff1 INT,
+	// 	log.Fatal(err)
-			delivered_tariff2 INT,
+	// }
-			returned_tariff1 INT,
+	// defer db.Close()
-			returned_tariff2 INT,
-			delivery_all INT,
-			returning_all INT,
-			failures INT,
-			long_failures INT,
-			gas INT,
-			voltage_l1 INT,
-			voltage_l2 INT,
-			voltage_l3 INT,
-			current_l1 INT,
-			current_l2 INT,
-			current_l3 INT,
-			delivery_l1 INT,
-			delivery_l2 INT,
-			delivery_l3 INT,
-			returning_l1 INT,
-			returning_l2 INT,
-			returning_l3 INT
-			);
-		-- SELECT create_hypertable('p1', 'timestamp', if_not_exists => TRUE);
-	`)
-	if err != nil {
-		log.Fatal("Error creating table:", err)
-	}
 
 	// Initialize MQTT options
 	opts := mqtt.NewClientOptions()
@@ -184,3 +149,59 @@ func insertData(timestamp time.Time, payload Payload) error {
 	)
 	return err
 }
+
+func connectToPostgreSQL(pgConnStr string) error {
+	// Connect to PostgreSQL
+	var err error
+	for {
+		db, err = sql.Open("postgres", pgConnStr)
+		if err == nil {
+			break // Successfully connected
+		}
+
+		log.Println("Error connecting to PostgreSQL:", err)
+		time.Sleep(5 * time.Second) // Retry after 5 seconds
+	}
+
+	// Enable TimescaleDB
+	_, err = db.Exec(`
+		CREATE EXTENSION IF NOT EXISTS timescaledb;
+	`)
+	if err != nil {
+		log.Fatal("Error creating TimescaleDB extension:", err)
+	}
+
+	// Create table if not exists
+	_, err = db.Exec(`
+		CREATE TABLE IF NOT EXISTS p1 (
+			timestamp TIMESTAMPTZ,
+			delivered_tariff1 INT,
+			delivered_tariff2 INT,
+			returned_tariff1 INT,
+			returned_tariff2 INT,
+			delivery_all INT,
+			returning_all INT,
+			failures INT,
+			long_failures INT,
+			gas INT,
+			voltage_l1 INT,
+			voltage_l2 INT,
+			voltage_l3 INT,
+			current_l1 INT,
+			current_l2 INT,
+			current_l3 INT,
+			delivery_l1 INT,
+			delivery_l2 INT,
+			delivery_l3 INT,
+			returning_l1 INT,
+			returning_l2 INT,
+			returning_l3 INT
+			);
+		SELECT create_hypertable('p1', 'timestamp', if_not_exists => TRUE);
+	`)
+	if err != nil {
+		log.Fatal("Error creating table:", err)
+	}
+
+	return nil
+}