title: How to check in node if module exists and if exists to load?
body: <p>I need to check if file/(custom)module js exists under some path. I tried like</p>
  
  <p><code>var m = require('/home/test_node_project/per');</code><br>
  but it throws error when there is no per.js in path. 
  I thought to check with
   <code>fs</code> if file exists but I don't want to add <code>'.js'</code> as suffix if is possible to check without that.
  How to check in node if module exists and if exists to load ?</p>