[Feature]: Create GitHub Action to block PRs from ${fork}/main branch

[varshith257]

Requirement

We should set up a new workflow that will fail if the PR is submitted from main branch. This workflow should be added to jearger/jarger-ui/documentation repositories (perhaps we need a reusable action - only if the check logic is reasonably complex).

Problem

Making PR changes on the main branch of a fork is a bad practice, and breaks some of our workflows that check if the current branch is main before doing certain steps (like trying to push to Docker).

Proposal

No response

Open questions

No response

[varshith257]

It is a part of:

• Create GitHub Action to block PRs from ${fork}/main branch jaeger#5271

[varshith257]

@yurishkuro Here in this repo I can't find any GitHub actions. Should I add this functionality as a separate workflow in this repo?

[yurishkuro]

you can refer to the action from the main repo and add it to lint workflow

[varshith257]

you can refer to the action from the main repo and add it to lint workflow

@yurishkuro Can guide this how can we link with main repo action? So that it can be make ease for me to raise a PR. I tried it before when issue created but didn't get a work around solution

[yurishkuro]

In the main repo we call the actions via relative path

    - name: Ensure PR is not on main branch
      uses: ./.github/actions/block-pr-not-on-main

In the other repos I think you can call the same action via full path jaegertracing/jaeger/.github/actions/block-pr-not-on-main@main

If that doesn't work for actions, it should definitely work for helper workflows according to the docs https://docs.github.com/en/actions/using-workflows/reusing-workflows#example-caller-workflow