title: shinyapps.io- Failed to load resource: the server responded with a status of 500 (Internal Server Error)
body: <p>I have an app that I've uploaded to shinyapps.io, and I've been noticing some instability that I can't trace.  The app has a bunch of different reactive inputs which call code to filter, calculate, and plot some data.  Occasionally, a certain sequence of selecting these inputs causes the site to freeze and trigger a 500 Internal Server Error.</p>
  
  <p>Strangely enough, when I execute the same commands on a locally-hosted (thru R) version of the app, I don't get an error.</p>
  
  <p>It's a really booger to trace: any suggestions on what may be causing the problem and/or how to debug it better? I'm a javascript novice, so any help would be appreciated.</p>
  
  <p>Full representative error log:</p>
  
  <pre><code>/opt/shiny-server/scripts/shiny-run: line 3:    32 Killed    
  /bin/bash --login -c   "$SHINY_EXEC_COMMAND $SHINY_R_PATH $*"
  
  Failed to load resource: the server responded with a status of 500 (Internal Server Error) 
  &lt;&lt;site@shinyapps.io&gt;&gt;/shared/bootstrap/css/bootstrap-responsive.min.css
  
  Failed to load resource: the server responded with a status of 500 (Internal Server Error) 
  &lt;&lt;site@shinyapps.io&gt;&gt;/shared/bootstrap/css/bootstrap.min.css
  
  Failed to load resource: the server responded with a status of 500 (Internal Server Error) 
  &lt;&lt;site@shinyapps.io&gt;&gt;/shared/font-awesome/css/font-awesome.min.css
  
  Failed to load resource: the server responded with a status of 500 (Internal Server Error) 
  &lt;&lt;site@shinyapps.io&gt;&gt;/shared/datatables/css/DT_bootstrap.css
  </code></pre>