Add instructions using actions/cache to README

[mering]

Newer versions of actions/cache have resolved previous issues. Prefer this over third party actions.

[viceice]

related to

• Unable to use actions/cache with Renovate: EACCESS #646

[mering]

@viceice Thanks. In the current version of the README using a third party action there is also an explicit chown call necessary.

[viceice]

feel free to open a PR to update the readme 🤗

[AB-xdev]

Hey,

we had the same problem and created a working version.

renovate.yml

name: Renovate

on:
  # This lets you dispatch a renovate job with different cache options if you want to reset or disable the cache manually.
  workflow_dispatch:
    inputs:
      repoCache:
        description: 'Reset or disable the cache?'
        type: choice
        default: enabled
        options:
          - enabled
          - disabled
          - reset
  schedule:
    - cron: '0 0 * * *'

permissions: 
  actions: write # Required to delete existing cache
  contents: read 

# Adding these as env variables makes it easy to re-use them in different steps and in bash.
env:
  # This is the dir renovate provides -- if we set our own directory via cacheDir, we can run into permissions issues.
  # It is also possible to cache a higher level of the directory, but it has minimal benefit. While renovate execution
  # time gets faster, it also takes longer to upload the cache as it grows bigger.
  cache_dir: /tmp/renovate/cache/renovate/repository
  # This can be manually changed to bust the cache if necessary.
  cache_key: renovate-cache

jobs:
  renovate:
    name: Renovate
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Restore cache
        if: github.event.inputs.repoCache != 'disabled'
        id: cache-restore
        uses: actions/cache/restore@v4
        with:
          path: ${{ env.cache_dir }}
          key: ${{ env.cache_key }}

      - name: Try fix cache permissions
        if: ${{ steps.cache-restore.outputs.cache-hit }}
        continue-on-error: true
        run: |
          set -x
          
          # Unfortunately, the permissions expected within renovate's docker container
          # are different than the ones given after the cache is restored. We have to
          # change ownership to solve this. We also need to have correct permissions in
          # the entire /tmp/renovate tree, not just the section with the repo cache.
          sudo chown -R 12021:0 /tmp/renovate/
          ls -R $cache_dir

      - uses: renovatebot/github-action@v41.0.13
        with:
          configurationFile: self-hosted.json5
          token: ${{ secrets.RENOVATE_TOKEN }}
        env:
          # This enables the cache -- if this is set, it's not necessary to add it to renovate.json.
          RENOVATE_REPOSITORY_CACHE: ${{ github.event.inputs.repoCache || 'enabled' }}

      - name: Delete previous cache
        if: ${{ github.event.inputs.repoCache != 'disabled' && steps.cache-restore.outputs.cache-hit }}
        continue-on-error: true
        # GitHub CLI is already preinstalled on the runner
        run: gh cache delete "${{ env.cache_key }}"
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      - name: Save cache
        uses: actions/cache/save@v4
        if: github.event.inputs.repoCache != 'disabled'
        with:
          path: ${{ env.cache_dir }}
          key: ${{ env.cache_key }}

in use at: https://github.com/xdev-software/renovate-selfhosted

Should I create a PR?