Added dotenv parsing, cleared up style errors.

main.go

@@ -6,23 +6,37 @@ import (
 	"os"
 	"strconv"
 
+	"github.com/joho/godotenv"
+
 	"darjeeling.systemec.nl/rhouben/fibonacci/functions"
 )
 
 func main() {
-	var port_number int
+	var port_number int = 8098 // hard default
 	var error error
 	var bind_socket string
 	fmt.Println("Hello, world. I'm teaching myself Go.")
 
-	if len(os.Args) <= 1 {
-		port_number = 8088
-	} else {
-		port_number, error = strconv.Atoi(os.Args[1])
+	error = godotenv.Load() // Load .env file
+	if error != nil {
+		fmt.Printf("Error trying to load .env file: %s\n", error)
+	}
+	port_arg := os.Getenv("FIB_PORT")
+	if port_arg != "" {
+		fmt.Printf("Loaded port value '%s' from environment.\n",
+			port_arg)
+	}
+	if len(os.Args) > 1 { // commandline overrules env
+		port_arg = os.Args[1]
+		fmt.Printf("Loading port value '%s' from command line.\n",
+			port_arg)
+	}
 
+	if port_arg != "" {
+		port_number, error = strconv.Atoi(port_arg)
 		if error != nil {
-			fmt.Printf("I had an error trying to parse %s into a number: %s\n",
-				os.Args[1],
+			fmt.Printf("I had an error trying to parse '%s' into a number: %s\n",
+				port_arg,
 				error)
 			os.Exit(0)
 		}