Fix code formatting github action

[vfdev-5]

🐛 Bug description

Currently, auto code formatting GA: https://github.com/pytorch/ignite/actions/workflows/code-style.yml
does not on forks and fails while try to commit/push the fix to the fork. This gives a misleading error to the user without helping how to solve it. Currently this action is disabled.

The idea is to find out what is the cause of the failure and fix it if possible.

Environment

• PyTorch Version (e.g., 1.4):
• Ignite Version (e.g., 0.3.0):
• OS (e.g., Linux):
• How you installed Ignite (conda, pip, source):
• Python version:
• Any other relevant information:

[Devanshu24]

Hi @vfdev-5 !
I could try fixing this, the problem is the user has to enable GitHub actions on their fork (which GitHub disables by default)
We could add a line in CONTRIBUTING.md suggesting if you want to use auto formating please enable GitHub actions on your fork. :)

[vfdev-5]

@Devanshu24 thanks for the info! Do you know if still there is a way to use/skip this action if user disabled actions ?

[Devanshu24]

I do not at this moment, but I'll look it up! :)

[trsvchn]

@vfdev-5

Actions are disabled by default for forked repos (as @Devanshu24 already mentioned). When you're creating a PR to upstream repo (pytorch/ignite) it triggers worklfow from that repo (pytorch/ignite).

If you want to use GH Actions you need to toggle them manually for your fork. Then, if you're creating PR or pushing to the fork repo (user/ignite) it triggers local workflow (workflow file from the fork repo will be used).

What kind of error do we have? I am going to reproduce it in my fork.

I think, it should work fine. Maybe this issue is related to permissions and GH Token, maybe user has to use Personal GitHub token or smth.

[trsvchn]

I've made some tests. Here #1663 you can see a PR with autopep8 fix made for a dummy python file in a fork w/o failure. so, it works as expected.

But the most interesting thing happens when you're trying to add new commits to that branch, it triggers 2 same workflows simultaneously: one for push and one for pr:

push action pushes new commit to the branch causing PR action to fail:
https://github.com/trsvchn/ignite/runs/1946163291?check_suite_focus=true#step:5:54:

  ! [rejected]        HEAD -> local-code-style (non-fast-forward)
error: failed to push some refs to 'https://github.com/trsvchn/ignite'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.

[trsvchn]

so we have double triggering here, and there is no easy way to fix it:

I’m afraid that you cannot do this directly. However, you can trigger only on pushes to master, or pull requests to master. This will prevent builds from happening twice when somebody opens a pull request against master and then pushes updates to their branch. For example: ...

Full: https://github.community/t/how-to-trigger-an-action-on-push-or-pull-request-but-not-both/16662

And our code-style workflow configured for all branches, that's why we have such behavior.

[trsvchn]

well, setting this really triggers only one workflow:

on:
  push:
    branches:
    - master
  pull_request:
    branches:
    - master

But, again it will work against master branch:
trsvchn#7

[trsvchn]

I think the possible solution might be to create two separate workflow files:
main code-style with:

on:
  push:
    branches:
    - master
  pull_request:
    branches:
    - master

and another for non-master/forks events, only for push events

on:
  push:
    branches:
    - "!master"

But we need to discuss it (and verify it)

[vfdev-5]

@trsvchn thanks for inspecting that !

What kind of error do we have? I am going to reproduce it in my fork.

Here is a log where GA has failed :

• https://github.com/pytorch/ignite/runs/1936462365?check_suite_focus=true
• https://github.com/pytorch/ignite/actions/workflows/code-style.yml

It is stefanzweifel/git-auto-commit-action@v4 which fails if there are files to format the code.

Yes, there is also this issue when we push a branch to the origin and its PR has 2 actions : for push and pull_request...
But i'd say it is another issue :)

[trsvchn]

@vfdev-5 ok, I see, it's different. Thanks, I will try to play that dummy PR to reproduce exactly that error. But, auto-formatting for forked repo with enabled actions works fine.

[trsvchn]

@vfdev-5 After quick view at the stefanzweifel/git-auto-commit-action@v4 I found this recomendation:

You must use action/checkout@v2 or later versions to checkout the repository. In non-push events, such as pull_request, make sure to specify the ref to checkout:

- uses: actions/checkout@v2
  with:
    ref: ${{ github.head_ref }}

And, also, there is a recipe how to use it with forks:

https://github.com/stefanzweifel/git-auto-commit-action#using-the-action-in-forks-from-public-repositories

And this:

For Workflows which runter linters and fixers (like the example above) we recommend running them when a push happens on the master-branch.

[vfdev-5]

Thanks for the info and the link. Shouldn't we do like in the example: https://github.com/stefanzweifel/git-auto-commit-action#example-2 but adapted for us :

• add pull_request_target

We can inspect what happens in both cases:
a) GitHub Action is enabled on the forked repository.
b) GitHub Action is disabled on the forked repository.

[trsvchn]

@vfdev-5 yes, I think we can start from that