How to clean up node modules?

#node #javascript #npm

When building a Node.js application you install a various amount of npm modules, the package.json and node-modules folder grow. It is best practice minimizing the code you have to maintain, and this is also true for npm packages.

Clean up node_modules/ folder

There are two ways to clean up the node_modules folder:

Delete the folder and reinstall
Use npm prune (starting with npm version 6)

Manually remove and reinstall

You could remove your node_modules/ folder and then reinstall the dependencies from package.json.

Remove all your packages (for Windows users: you can use Git Bash to run this command):

rm -r node_modules/

Install packages:

npm install

Remove extraneous packages with NPM prune

Synopsis: npm prune [[<@scope>/]<pkg>...] [--production] [--dry-run] [--json]

npm prune removes extraneous packages. If a package name is provided, then only packages matching one of the supplied names are removed. Extraneous packages are those present in the node_modules folder, but not listed as any package's dependency list.

You can provide the following flags:

--production - If the --production flag is specified, or the NODE_ENV environment variable is set to production, the packages specified in your devDependencies will be removed.
--no-production will negate NODE_ENV being set to production.
--dry-run indicates that you don't want npm to make any changes and that it should only report what it would have done.
--json changes that npm prune made or would have made with --dry-run are printed as a JSON object.

Extraneous modules are pruned automatically (normal operations), hence this command is only needed with the --production flag. Though, operation is not always normal as it should be and crashes and mistakes happen. The command npm prune can help clean up resulting garbage of crashes.

TL;DR

npm prune removes not listed packages in the node_modules folder.
The flag --dry-run is useful to see what would be removed.
When crashes or mistakes happen, npm prune can help clean up any resulting garbage.

Thanks for reading and if you have any questions , use the comment function or send me a message @mariokandut.

If you want to know more about Node, have a look at these Node Tutorials.