option to specify minimum length for upstream nicks

NTFConfig.go

@@ -11,6 +11,7 @@ type NTFConfig struct {
 	HubAddr         string
 	HubDescription  string
 	HubSecNick      string // Nickname of Hub-Security to exclude (e.g. "PtokaX")
+	HubNickMinChars int
 	BotAPIKey       string
 	GroupChatID     int64
 

NTFServer.go

@@ -544,6 +544,12 @@ func (this *NTFServer) HandleDirectMessage(update telegram.Update) error {
 
 	} else if strings.HasPrefix(msg, "/join ") {
 		requestedHubNick := msg[6:]
+
+		// Minimum nick lengths
+		if len(requestedHubNick) < this.config.HubNickMinChars {
+			return respond(fmt.Sprintf("Upstream nickname '%s' should be at least %d characters long", requestedHubNick, this.config.HubNickMinChars))
+		}
+
 		err := this.registerUser(userID, requestedHubNick)
 		if err != nil {
 			log.Printf("Failed to register user: %s", err.Error())