Adds serial port to serial transport

Change-type: minor
Signed-off-by: Alex Bucknall <[email protected]>

notecard/main.go

@@ -16,6 +16,9 @@ const (
 	I2C    = "i2c"
 )
 
+const defaultSerialDevice = "/dev/tty.usbmodemNOTE1"
+const defaultSerialBaud = "9600"
+
 type server struct {
 	card      *notecard.Context
 	initError error
@@ -86,7 +89,14 @@ func setupNotecard(protocol string) (*notecard.Context, error) {
 	}
 
 	if protocol == Serial {
-		card, err := notecard.OpenSerial("/dev/tty.usbmodemNOTE1", 9600)
+		serialPort := getEnv("NOTECARD_SERIAL_DEVICE", defaultSerialDevice)
+
+		baud, err := strconv.Atoi(getEnv("NOTECARD_SERIAL_BAUD", defaultSerialBaud))
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NOTECARD_SERIAL_BAUD: %v", err)
+		}
+
+		card, err := notecard.OpenSerial(serialPort, baud)
 		if err != nil {
 			return nil, fmt.Errorf("error opening Notecard: %v", err)
 		}