Allow caching for deployment events or other events without GITHUB_REF

As suggested in #317 and #318, I would like to be able to use actions/cache for events where the GITHUB_REF environment variable is not necessarily defined.

For example, I currently have decoupled the creation and the processing of deployments.

• one ore more workflows create deployment (with differing payloads) using the Deployments API
• a workflow is triggered by a deployment event and process the actual deployment to different environments

Currently, even with #263, it is not possible to use caching for the deployment event (see @joshmgross’ comments in #317). Consequently, deployments using a workflow setup describes as above either take a lot longer, or are not feasible.

It would be really nice to be able to use actions/cache with a setup as described!

Let me know if there is anything I can do to help push this feature through the door.

🌱

[Fedeorlandau]

This would be massive for us. We’re running cypress after Vercel’s deployment.

name: Run E2E Tests
on: [deployment_status]
jobs:
  e2e:
    if: github.event.deployment_status.state == 'success'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/setup-node@v2
        with:
          node-version: '14'
          cache: 'yarn'
      - run: yarn
      - run: yarn cypress:headless --env host=${{ github.event.deployment_status.target_url }}

[RichiCoder1]

Would love this for the exact reason of deployment events.