[Feature] Does Yarn 2 have any sort of global cache?

Describe the user story

Yarn 1 had a useful feature — it stored global cache, for example in folder /usr/local/share/.cache/yarn, which could be revealed by running yarn cache dir.

Having cache like this allowed to mount it to CI runner so that all jobs on runner will have shared cache, and it will be much faster rather than to cache Yarn’s cache per-job.

Yarn 2 does not have such command.

Describe the solution you’d like

Same thing as before. Global cache which will be used as fallback if project’s .yarn/cache is empty.

[kirill-konshin]

@phuctm97 in my case yarn config get cacheFolder returns me %PROJECT_DIR%/.yarn/cache which is project’s folder, not system-wide cache folder.

@arcanis I think this issue has to be reopened, since it will give a lot of benefits for CI like Gitlab. There’s still no solution how to determine which system-wide folder Yarn 2 is using. enableGlobalCache is a bit different, I need both:

1. local cache (to cache it using Gitlab, per branch)
2. global cache (same as in Yarn 1) to speed up when local cache is cold (first checkout of branch).

[phuctm97]

@kirill-konshin I share the same use case with you that I want to be able to save/attach cache to optimize CI/CD resources.

I ended up caching Yarn’s local cache folder and everything works just fine. Why don’t you do that, is there any complication or unseen issue, or you just didn’t think of it?

Following is how I cache Yarn’s local cache folder and the results:

jobs:
  build:
    runs-on: ubuntu-latest
    env:
      node-version: 12.x
    steps:
      - name: Checkout
        uses: actions/checkout@v2
      - name: Setup Node.js ${{ env.node-version }}
        uses: actions/setup-node@v1
        with:
          node-version: ${{ env.node-version }}
      - id: find-yarn-cache-folder
        name: Find Yarn's cache folder
        run: echo "::set-output name=path::$(yarn config get cacheFolder)"
      - name: Cache Yarn's cache folder
        uses: actions/cache@v1
        with:
          path: ${{ steps.find-yarn-cache-folder.outputs.path }}
          key: yarn-cache-folder-os-${{ runner.os }}-node-${{ env.node-version }}-${{ hashFiles('yarn.lock') }}
          restore-keys: |
            yarn-cache-folder-os-${{ runner.os }}-node-${{ env.node-version }}-
            yarn-cache-folder-os-${{ runner.os }}-
      - name: Install dependencies
        run: yarn install
        ...

• Before applying cache:

  441 packages were already cached, 1556 had to be fetched
  

• After applying cache:

  1994 packages were already cached
  

Updated CI/CD still bundles my application properly and saves ~85% build time.