Use actions/setup-node to cache pnpm store instead of doing it manually

[dtinth]

actions/setup-node supports the option cache: pnpm, so we can take advantage of that to make our workflow simpler.

Note: pnpm/action-setup must be run BEFORE actions/setup-node because otherwise the setup-node action will fail due to not being able to find the pnpm executable.

[menasheh]

Haven't tried the old way for comparison, but can confirm this way works.

[robotkutya]

Anyone knows what the difference is between the two methods?
#82

[nicolassanmar]

I don't know if I have set this up incorrectly, but I find the manual way to be faster than using the cache from setup-node.

The manual way does not require us to install the packages again (as we cache node_modules), while this suggested one does require it:

Manual (~20s)

Using setup-node (~1m)

(This was a cache hit)

setup-node step config

    - name: Install pnpm
      uses: pnpm/action-setup@v2
      with:
        version: 8.1.0
        run_install: false

    # Has to be done after installing pnpm, otherwise the cache will not work.
    - name: Install Node.js
      uses: actions/setup-node@v3
      with:
        node-version: 18
        cache: pnpm
        cache-dependency-path: 'pnpm-lock.yaml'

[dtinth]

@nicolassanmar Does your “manual” setup also cache node_modules? Using cache: pnpm merely caches the pnpm store, not node_modules.

This is how I interpret the log message:

Log message	Description
resolved X, reused 0, downloaded X, added X, done	Cache is not working.
resolved X, reused X, downloaded 0, added X, done	Store cache is working.
Already up to date	node_modules is cached.

[nicolassanmar]

@dtinth You are 100% right. I thought that https://github.com/pnpm/action-setup#use-cache-to-reduce-installation-time suggested caching node_modules but I was mistaken.
I am manually caching node_modules and I don't think setup-node provides a way to do that
They stated that it is not supported and they are not planning to add it actions/setup-node#406 (comment)

[robotkutya]

thanks guys for the discussion, makes it much more clear!

I think more info about this would be appreciated to newcomers, any ideas how to improve the docs in this regard?

[FFdhorkin]

I would highly suggest you show both as two different options (as opposed to replacing the existing one) - this solution won't work if you're using a self-hosted runner that has node pre-installed

[davidlj95]

pnpm docs also mention using setup-node to cache pnpm store

https://pnpm.io/continuous-integration#github-actions

I think we should update the example to go the recommended way by using setup-node. I think that would be the recommended way given you don't have to maintain a custom cache. setup-node takes care of that for you (what if pnpm store command is deprecated and now another one is used? setup-node would take care of that). So a thing less to worry about

Links:

• Docs source
• Docs source PR where GitHub Actions + setup-node is added