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

I installed gulp and when I ran this gulp command in the command line I got a gulp: command not found error. It appeared that it installed gulp in my local folder that is /home/YOURUSERNAME/.node/lib/node_modules and not in the global npm folder.

You can check npm root folder by running this command: npm root -g, which was returning my personal directory /home/YOURUSERNAME/.node/lib/node_modules and not the expected /usr/local/lib/node_modules.

You can fix this by running npm config set prefix /usr/local command.

Answer 2

It looks like the easiest way to do this is to run npm install from your app's folder. This tells npm to hook everything up.

It's the last instruction after express <appname>:

...
dont forget to install dependencies:
$ cd <appname> && npm install

Answer 3

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

Answer 4

I had the same problem. This worked for me though:

Seems like npm (now?) installs node modules to /usr/local/lib/node_modules/ and not /usr/local/lib/node/

What I did was simply to copy everything from node_modules to node: sudo cp -r /usr/local/lib/node_modules/* usr/local/lib/node/ and now it seems to be working for me.

Hope this helps you :-)

Answer 5

On Ubuntu 12.04 you have to add the export NODE_PATH=/usr/local/lib/node_modules to your /.bashrc to use globally installed modules.

Answer 6

for mac users

cd /usr/local/lib/node
sudo ln -s ../node_modules/* ./$1