Allow --mapping argument to be repeated or comma-separated

cmd/mc-router/main.go

@@ -30,7 +30,7 @@ type MetricsBackendConfig struct {
 
 type Config struct {
 	Port                 int      `default:"25565" usage:"The [port] bound to listen for Minecraft client connections"`
-	Mapping              string `usage:"Comma-separated mappings of externalHostname=host:port"`
+	Mapping              []string `usage:"Comma-separated or repeated mappings of externalHostname=host:port"`
 	ApiBinding           string   `usage:"The [host:port] bound for servicing API requests"`
 	Version              bool     `usage:"Output version and exit"`
 	CpuProfile           string   `usage:"Enables CPU profiling and writes to given path"`
@@ -137,11 +137,9 @@ func main() {
 	logrus.Info("Stopping")
 }
 
-func parseMappings(val string) map[string]string {
+func parseMappings(vals []string) map[string]string {
 	result := make(map[string]string)
-	if val != "" {
+	for _, part := range vals {
-		parts := strings.Split(val, ",")
-		for _, part := range parts {
 		keyValue := strings.Split(part, "=")
 		if len(keyValue) == 2 {
 			result[keyValue[0]] = keyValue[1]
@@ -149,7 +147,6 @@ func parseMappings(val string) map[string]string {
 			logrus.WithField("part", part).Fatal("Invalid part of mapping")
 		}
 	}
-	}
 
 	return result
 }