Catch the "invalid auth token" when run blynk.config(token)

Ideas
1

Hi,
Is it possible to be able to inform the user when she inputs a wrong auth token? I can get from serial port this: “Invalid auth token” but there is no way to raise a flag so I can inform my user.

Thank you,

2

I found a way to overcome this problem by sending a GET request to the blynk server:

http://blynk-cloud.com/TOKEN/project

If the response contains the word “name” then the token is valid. (I hope this function will help others or even help the blynk team to create a function to check the token)
(library used: #include <HTTPClient.h> )

int isBlynkTokenValid(String token)
{
  //TODO
  //RETURNS:
  /// HTTP client errors
  //  #define HTTPC_ERROR_CONNECTION_REFUSED  (-1)
  //  #define HTTPC_ERROR_SEND_HEADER_FAILED  (-2)
  //  #define HTTPC_ERROR_SEND_PAYLOAD_FAILED (-3)
  //  #define HTTPC_ERROR_NOT_CONNECTED       (-4)
  //  #define HTTPC_ERROR_CONNECTION_LOST     (-5)
  //  #define HTTPC_ERROR_NO_STREAM           (-6)
  //  #define HTTPC_ERROR_NO_HTTP_SERVER      (-7)
  //  #define HTTPC_ERROR_TOO_LESS_RAM        (-8)
  //  #define HTTPC_ERROR_ENCODING            (-9)
  //  #define HTTPC_ERROR_STREAM_WRITE        (-10)
  //  #define HTTPC_ERROR_READ_TIMEOUT        (-11)
  //(-100) --> No Wifi
  //(-99) --> token checked but is not valid
  //(1) --> OK
  //the function validates a blynk token and returns 1 if token is valid and negative if token is not valid
  //http://blynk-cloud.com/TOKEN/project <-- this will return "Invalid token" if the token is not valid (if its valid it will return a json file containing all project details
  
  if(WiFi.status() != WL_CONNECTED) WiFi.begin();
  int timeOutCounter = 0;
  while (WiFi.status() != WL_CONNECTED) 
  {
    delay(1000);
    timeOutCounter++;
    if(timeOutCounter > 10) break;
  }
  if(WiFi.status() == WL_CONNECTED)
  {        
    http.begin("http://blynk-cloud.com/" + token + "/project");
    
    int httpCode = http.GET();
    if (httpCode > 0 )
    {
      String payload = http.getString();
      if(payload.indexOf("name") >= 0)
      {
        http.end();
        return 1;
      }
      else
      {
        http.end();
        return -99;
      }
    }
    else
    {
      http.end();
      return httpCode;
    }
  }
  else 
  {
    return -100;
  }
}