title: rails: enforce validation check with form with multiple submit buttons
body: <p>I have a form with multiple submit buttons that trigger different functionality in controller action.  One submit button allows user to save csv with format. Another submit button allows user to load csv file with specified format from dropdown. Then a final submit button allows user to save actual formatted records to database. In order to save records, the user must either save csv format first or load a csv format. How can I enforce this validation check? How can I determine one of the other two submit buttons were triggered before the create call? </p>
  
  <p>The problem with using session variable will be if I add a boolean in session after one button submitted, then when they import another csv file, that value still will be in session and give false positive.</p>