How can we differentiate between release and pre-release at the git repo level?

[mhever]

We've nightly builds, building the latest images based on the ubuntu20 / ubuntu22 / win22 release tags. At the git repo level, how can we know if we're dealing with a release or a pre-release. Probably I'm missing the obvious. Recently we were fooled by actions/runner-images@d08c3d22

we built an image based on this tag, but 2 days later when we tried to check what's actually inside the release, the tag was gone.

[zioalex]

Good point,
we have the same problem.
Any guidance on how to find release or pre-release from git or in another way?

[DevOpsAzurance]

I use the following api:

https://api.github.com/repos/OWNER/REPO/releases/latest

To get the latest release. As for a pre-release, I'm not sure.

[mhever]

Thanks a lot! Apparently https://api.github.com/repos/actions/runner-images/releases lists all the information we need, including a bool flag prerelease. Perfect!

[erik-bershel]

Hey @mhever!
I have a couple of comments that may be useful to you:

• the prerelease tag means that we have started rolling out a new image, but it is far from a fact that your build will end up on the new runner;
• release branches are not repeatable, which means that if you are trying to build your own runners, they will not be 100% identical to the specified version of the GitHub or AzDO runners;
• with every minute after the prerelease, the chance that the code attached to the branch will stop executing due to the difference between the release branch and the main increases.

[Fran-Rg]

For myself in the future and anyone looking to have a workflow for prerelease and release working in every condition:

• draft -> prerelease == triggers on-prerelease
• draft -> release == triggers on-release
• prerelease -> release == triggers on-release
• prelease == triggers on-prerelease
• release == triggers on-release

Here's the pre-release workflow. NOTE: the if is required, the workflow will be called when creating a release directly but skipped :

---
name: on-prerelease
on:
  release:
    types:
      - published

jobs:
  test:
    if: github.event.release.prerelease
    runs-on: ubuntu-latest
    steps:
      - name: Echo
        run: |-
          echo "I am a pre-release"

and the release workflow:

---
name: on-release
on:
  release:
    types:
      - released

jobs:
  test:
    if: ${{ !github.event.release.prerelease }}
    runs-on: ubuntu-latest
    steps:
      - name: Echo
        run: |-
          echo "I am a release"