[node.js] Print a list of all installed node.js modules

Generally, there are two ways to list out installed packages - through the Command Line Interface (CLI) or in your application using the API.

Both commands will print to stdout all the versions of packages that are installed, as well as their dependencies, in a tree-structure.


CLI

npm list

Use the -g (global) flag to list out all globally-installed packages. Use the --depth=0 flag to list out only the top packages and not their dependencies.


API

In your case, you want to run this within your script, so you'd need to use the API. From the docs:

npm.commands.ls(args, [silent,] callback)

In addition to printing to stdout, the data will also be passed into the callback.