SOLR-15972 Add wrapper jar and export-ignore attr

[madrob]

Tested via: git archive --format tgz HEAD | tar -zt | grep wrapper

https://issues.apache.org/jira/browse/SOLR-15972

[janhoy]

As the no-binary requirement is for releases only, I guess this solution is acceptable.

[dweiss]

I'm not sure why you want to have the wrapper versioned - for me it's one way or the other. Since you can't publish it in source releases and the infrastructure to automatically download it is in place - why add things to make it more complicated?

[madrob]

I'm just trying to make my internal, non internet accessible CI work. Like I said on the Jira, I have a maven mirror but not a GitHub mirror. I suppose the other option is that I install gradle from somewhere and use that instead of the wrapper?

[dweiss]

bq. I'm just trying to make my internal, non internet accessible CI work

Fair enough. The only thing that comes to my mind is to download the wrapper manually and place it where it should be placed then. Another alternative for isolated networks would be a git mirror with that wrapper checked in on a downstream branch.

bq. I suppose the other option is that I install gradle from somewhere and use that instead of the wrapper?

Yes, if it's the same version, it'll work just fine.

[HoustonPutman]

Seems fine to me. If we have to remove it in the future, so be it, but this does solve the original reason it was taken away.

It's not a huge file (not nearly the biggest in our repo), and checking it in is recommended by Gradle.

[dweiss]

I'm +0. My view is very polarized - either remove the gradle wrapper download infrastructure or use it for what it was added. Occam's razor.

[madrob]

I ended up being able to install the full gradle version and use that for CI instead of trying to hack around the wrapper being missing.