Node_modules Be Gone: A Script for Removing Unused Node.js Dependencies

Background

As a Node.js developer I enjoy messing around with different side projects, and I’ll periodically clone a repository online, install the dependencies with NPM, and after a day or two I’ll move on to the next thing.

In order to run a Node app you need the packages, which are downloaded and placed in the project's node_modules folder when you run npm install (or yarn if you’re a bad boy). You need these packages in order to run the project, but they usually take up more space than the project code itself.

Then if you’re like me, you’re left with dozens of random projects in a folder called open-source in a folder called Misc, all of which containing MBs of code that is potentially deprecated.

These folders can waste valuable space on your hard drive, and it can be tedious to manually search through your project directories to find and delete them.

To help solve this problem, I created this script you can run on macOS to remove the node_modules folder for any project that hasn't been accessed in a given number of days (here I’m setting it to 30):

#!/bin/bash

# Set the threshold for inactivity in days
inactive_threshold=30

# Set the path to the folder you want to scan
proj_folder=~/Documents/Misc

# Find all project directories in the Documents folder that have a node_modules folder
# and haven't been accessed in over the inactive threshold
for project in $(find "$proj_folder" -type d -name node_modules -mtime +"$inactive_threshold" -print); do
  # Remove the node_modules folder for the project
  rm -rf "$project"
done
bash

This script will go through every project in the ~/Documents/Misc folder (this is where I clone projects I don’t care about). For every project has not been accessed within the inactive_threshold, it will remove the node_modules folder.

Running it on a schedule

You can run that script once in the folder(s) you want to clean. To run it daily, you can use the cron utility.

Open a terminal and type crontab -e. This will open the crontab file in your default text editor. Then add this line to the file (replacing /path/to/script.sh with the actual path to the script):

0 0 * * * /path/to/script.sh
bash

Save and close the file.

If you're unfamiliar with Vim: to edit you need to enter 'insert' mode by pressing i which you can exit with the Esc key. To save, type : to enter the prompt bar at the bottom, then type x and press Enter.

The script will now run daily at midnight and delete the node_modules folder for any project that hasn't been accessed in the past 30 days, freeing up storage on your hard drive.

Note: Make sure that you understand the implications of this before setting this up. This will essentially break Node projects after 30 days until you run npm install/yarn. You may want to alter the parameters for your use case.