CircleCI Hacks: Caching NPM Package Dependencies
CircleCI’s caching is wonky, here’s a way around the weirdness
Problem 1: Dynamic Cache Keys
Let’s begin by reading the documentation on CircleCI caching keys and templates. This is where we learn about cache keys, eg. myapp-{{ checksum "package-lock.json" }}, which enable you to relate your cache to the specific contents of a file (amongst other things).
This is a fantastic idea, because the cache should only be updated when the dependencies change, and that’s what’s indicated by changes to the package.json and package-lock.jsonfiles.
There are two ways to install packages with npm:
npm install
The first, npm install, will install the dependencies listed in thepackage.json file. This allows for npm to select the optimal versions of the upstream dependencies based on the version specifications in package.json as well as those in the package.json files of the aforementioned upstream dependencies.
