Express module not found when installed with NPM

Question

When I try to run the app.js file created by express, I get the following error:

$ node app.js

node.js:134
        throw e; // process.nextTick         


        

Answer 1

It appears that while npm had been updated to install global modules into /usr/local/lib/node_modules, Node's own require.paths does not yet reflect this change.

There are two reasonable solutions:

1. Add the following code to the top of your application:

   require.paths.push('/usr/local/lib/node_modules');
   

   • Pro: non-invasive, easy to add

   • Con: requires discipline, future versions of node will restrict access to require.paths

2. As root, execute:

   ln -s /usr/local/lib/node_modules /usr/local/lib/node
   

   • Pro: reasonably non-invasive

   • Con: requires root, modifies linux fs, might not survive system updates