Question

I’ve created a script to send SMS notifications once important message is received (in accordance with this tutorial).
But quite often I receive notifications, that script failed to finish successfully. Error message is Cannot connect to Gmail (line 13), line 13 is:

var threads = GmailApp.getUserLabelByName('SMS').getThreads();

How should I handle it? I.e. just to stop execution and wait for next run?

Answer 1

A nice way would be to wrap your code around in a while loop and a try catch block and try until the operation is successful.
Something like …

var retryCount = 0; 
var success = false ; 

while (!success & retryCount++ <=5 ){
  try{
    var threads = GmailApp.getUserLabelByName('SMS').getThreads();
    // Other code here 

    success = true; 
  }catch(ex){ 
    Logger.log(ex);
  }
  Utilities.sleep(1000);
}