What actually happens when we do npm clear cache --force

Question

I am working on angular and just in general i wanted to know what actually happens in the angular project when we execute command npm clear cache --force and what type of data is there in cache. Thanks in advance

Answer 1

As found here

npm stores cache data in an opaque directory within the configured cache, named _cacache. This directory is a cacache-based content-addressable cache that stores all http request data as well as other package-related data. This directory is primarily accessed through pacote, the library responsible for all package fetching as of npm@5.

All data that passes through the cache is fully verified for integrity on both insertion and extraction. Cache corruption will either trigger an error, or signal to pacote that the data must be refetched, which it will do automatically. For this reason, it should never be necessary to clear the cache for any reason other than reclaiming disk space, thus why clean now requires --force to run.

There is currently no method exposed through npm to inspect or directly manage the contents of this cache. In order to access it, cacache must be used directly.

npm will not remove data by itself: the cache will grow as new packages are installed.

To answer your question:

The cache stores all http request data as well as other package-related data

Answer 2

The clear cache delete all data out of the cache folder and --force "forces" npm to re-download all packages and install them again.