How to check in node if module exists and if exists to load?

Question

I need to check if file/(custom)module js exists under some path. I tried like

var m = require('/home/test_node_project/per');
but it throws error when there is no per.js in path. I thought to check with fs if file exists but I don't want to add '.js' as suffix if is possible to check without that. How to check in node if module exists and if exists to load ?

Answer 1

Require is a synchronous operation so you can just wrap it in a try/catch.

try {     var m = require('/home/test_node_project/per');     // do stuff } catch (ex) {     handleErr(ex); } 

Answer 2

You can just try to load it and then catch the exception it generates if it fails to load:

try {     var foo = require("foo"); } catch (e) {     if (e instanceof Error && e.code === "MODULE_NOT_FOUND")         console.log("Can't load foo!");     else         throw e; } 

You should examine the exception you get just in case it is not merely a loading problem but something else going on. Avoid false positives and all that.