title: Include a javascript file in Shiny app
body: <p>I need to include a js library into my Shiny app. Currently I use includeHTML to include the script directly into html codes. e.g. </p>
  
  <pre><code>includeHTML('URL.js')
  </code></pre>
  
  <p>The browser will show "Not Found" when I try to browser the js file if I use tags$script, e.g.</p>
  
  <pre><code>http://127.0.0.1:7106/URL.js
  
  tags$script(src = 'URL.js')
  </code></pre>
  
  <p>Now I put URL.js in the same folder of ui.r and server.r. </p>
  
  <p>Where I should store the URL.js file? Or are there other ways to include a js file?</p>
  
  <p>Thanks for any suggestions.</p>