title: Large file upload on Heroku (NodeJS + Express)
body: <p>I am a total beginner in web development using MEAN Stack. I am considering to deploy my app on Heroku for this particular project. I am trying to create an application where the user would upload large excel files(<strong>>200MB</strong>). The application needs to process the excel file and then export the resultant file of similar size to another service. It is very hard for me to figure out the following:</p>
  
  <ol>
  <li>Would it be possible to save a file on disk in Heroku?</li>
  <li>For this process do I need to save the file somewhere on server at all, or would it be possible to just process the file keeping in memory and then export?</li>
  <li>Would it be possible to process large files from disk or should I try to save the information in a database?</li>
  <li>Are there any Heroku constraints that limit the size of file to be processed within memory?</li>
  </ol>
  
  <p>The information I have looked up seems too involved to be understood by a beginner like me. I haven't had much success with what I have tried and I don't want to spend too much time trying all these possibilities. </p>
  
  <p>How should I proceed? </p>
  
  <p>Thanks.</p>