Find unused npm packages in package.json

Question

Is there a way to determine if you have packages in your package.json file that are no longer needed?

For instance, when trying out a package and later commenting o

Answer 1

If you're using a Unix like OS (Linux, OSX, etc) then you can use a combination of find and egrep to search for require statements containing your package name:

find . -path ./node_modules -prune -o -name "*.js" -exec egrep -ni 'name-of-package' {} \;

If you search for the entire require('name-of-package') statement, remember to use the correct type of quotation marks:

find . -path ./node_modules -prune -o -name "*.js" -exec egrep -ni 'require("name-of-package")' {} \;

or

find . -path ./node_modules -prune -o -name "*.js" -exec egrep -ni "require('name-of-package')" {} \;

The downside is that it's not fully automatic, i.e. it doesn't extract package names from package.json and check them. You need to do this for each package yourself. Since package.json is just JSON this could be remedied by writing a small script that uses child_process.exec to run this command for each dependency. And make it a module. And add it to the NPM repo...

Answer 2

if you want to choose upon which giant's shoulders you will stand

here is a link to generate a short list of options available to npm; it filters on the keywords unused packages

https://www.npmjs.com/search?q=unused%20packages