Fixes #5500 - Add a GitHub Actions workflow that builds the docs

[martin-g]

Which issue does this PR close?

Closes #5500

Rationale for this change

Deploy the Datafusion website whenever a change is made in the docs/ folder.

What changes are included in this PR?

A new Github Action is introduced that builds the docs and copies them to asf-site branch

Are these changes tested?

Yes, I have tested them in my fork.

Are there any user-facing changes?

No

[martin-g]

This PR is a follow up of #5631

Last successful run of the new docs GHA workflow could be seen at https://github.com/martin-g/arrow-datafusion/actions/runs/4479933269/jobs/7874551780
Content of asf-site branch in my fork: https://github.com/martin-g/arrow-datafusion/tree/asf-site

[martin-g]

TODOs for the Datafusion committers:

1. create asf-site branch in arrow-datafusion repo
2. delete the datafusion folder in arrow-site repo

[martin-g]

CC @kou @alamb

[kou]

1. create asf-site branch in arrow-datafusion repo

Done.

[alamb]

I tested this PR out in my fork and it works great! Thank you @martin-g

Here https://github.com/alamb/arrow-datafusion/tree/asf-site

What are the next steps after this PR to actually get this site served?

On my fork I configured github pages:

And it published https://github.com/alamb/arrow-datafusion/actions/runs/4483635485 which is cool

But the site looks pretty bad https://alamb.github.io/arrow-datafusion

[alamb]

2. delete the datafusion folder in arrow-site repo

Here is a PR to do this apache/arrow-site#336

[alamb]

Seems like a step forward to me 👍

It would be nice to sort out how this content will be hosted (though maybe I just don't understand how the process works)

Thanks again @martin-g and @kou for your work in this area

[alamb]

However, when I check out the site locally and open it, it works great 👍

So I think that means the issue is with how github pages is publishing it

[kou]

We need to add .nojekyll to the asf-site like https://github.com/apache/arrow-site/blob/main/.github/workflows/deploy.yml#L112 to use GitHub Pages for preview.
If we don't have .nojekyll, our asf-site contents are processed by Jekyll. Jekyll ignores _*. So _static/styles/* aren't published on GitHub Pages.

[kou]

+1

[kou]

It would be nice to sort out how this content will be hosted (though maybe I just don't understand how the process works)

ASF provides https://arrow.apache.org/ (not GitHub Pages) that serves the contents in https://github.com/apache/arrow-site/tree/asf-site .
With the .asf.yaml configuration in this PR, https://arrow.apache.org/datafusion/ uses https://github.com/apache/arrow-datafusion/tree/asf-site instead of https://github.com/apache/arrow-site/tree/asf-site/datafusion .

[alamb]

I tested the latest and greatest code on my fork and it seems to have worked great! https://alamb.github.io/arrow-datafusion/

Thank you so much @martin-g and @kou

I am going to merge this PR and see how it goes!

[alamb]

I am happy to report that the first run of https://github.com/apache/arrow-datafusion/actions/runs/4488868585/jobs/7893990469 has worked

And the content appears to be on https://github.com/apache/arrow-datafusion/tree/asf-site 👍

I am going to test making changes to the datafusion site and verify they appear on https://arrow.apache.org/datafusion/

[alamb]

My test shows that the process is working : #5500 (comment)

Thanks again @kou and @martin-g -- this is really great.

[alamb]

PR to update release process: #5687

[alamb]

Here is a proposal to get the logo back : #5688