[SPARK-51104][DOC] Self-host JavaScript and CSS in Spark website

[gengliangwang]

What changes were proposed in this pull request?

Currently, the Spark website fails to load bootstrap.bundle.min.js/jquery.js/etc due to the following errors

Refused to load the stylesheet '<URL>' because it violates the following Content Security Policy directive: "style-src 'self' 'unsafe-inline' data:". Note that 'style-src-elem' was not explicitly set, so 'style-src' is used as a fallback.
Understand this errorAI
latest/:1 Refused to load the script 'https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.js' because it violates the following Content Security Policy directive: "script-src 'self' 'unsafe-inline' 'unsafe-eval' https://analytics.apache.org/". Note that 'script-src-elem' was not explicitly set, so 'script-src' is used as a fallback.
Understand this errorAI
latest/:1 Refused to load the script 'https://code.jquery.com/jquery.js' because it violates the following Content Security Policy directive: "script-src 'self' 'unsafe-inline' 'unsafe-eval' https://analytics.apache.org/". Note that 'script-src-elem' was not explicitly set, so 'script-src' is used as a fallback.
...

As a result, the website looks like:

To fix the issue, I suggest using self-host javascript and CSS in Spark website

Why are the changes needed?

Fix the broken styling on the Spark website.

Does this PR introduce any user-facing change?

No

How was this patch tested?

Test locally

Was this patch authored or co-authored using generative AI tooling?

No

[gengliangwang]

Note: after this PR, there is still one error:

Refused to load the script 'https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML' because it violates the following Content Security Policy directive: "script-src 'self' 'unsafe-inline' 'unsafe-eval' https://analytics.apache.org/". Note that 'script-src-elem' was not explicitly set, so 'script-src' is used as a fallback.

The mathjax lib is big and it doesn't seem reasonable to self-host it.

[LuciferYang]

+1, LGTM

[nchammas]

Not to distract from the main purpose of this PR, but are you able to build the PySpark API docs locally without hitting memory errors? (Mentioning this only because it was part of my email thread reporting the broken CSS link.)

[dongjoon-hyun]

+1, Thank you!

[gengliangwang]

but are you able to build the PySpark API docs locally without hitting memory errors?

@nchammas This question isn't related to this PR, but I couldn't build the PySpark API docs on macOS using the following command:

SKIP_SCALADOC=1 SKIP_RDOC=1 SKIP_SQLDOC=1 bundle exec jekyll serve

[nchammas]

@nchammas This question isn't related to this PR, but I couldn't build the PySpark API docs on macOS using the following command:

SKIP_SCALADOC=1 SKIP_RDOC=1 SKIP_SQLDOC=1 bundle exec jekyll serve

OK, so it's not just me. I will follow-up on this issue back on the dev list.

[LuciferYang]

@nchammas This question isn't related to this PR, but I couldn't build the PySpark API docs on macOS using the following command:

SKIP_SCALADOC=1 SKIP_RDOC=1 SKIP_SQLDOC=1 bundle exec jekyll serve

OK, so it's not just me. I will follow-up on this issue back on the dev list.

#48860 @panbingkun has provided a developer script to build docs locally using a Docker image.

[nchammas]

#48860 @panbingkun has provided a developer script to build docs locally using a Docker image.

Yes, I tried that, but got the same result. I think I need a way to tinker with the memory settings Spark uses when run by Sphinx. I am surprised the build here on GitHub is unaffected.

Let's continue the discussion on the dev list so we don't pester the folks on this thread here.

[gengliangwang]

@LuciferYang @HyukjinKwon @dongjoon-hyun @nchammas thanks for the reviews. I am merging this one to master/branch-4.0/branch-3.5

[panbingkun]

LGTM late.