Automatically wire up the --enable-preview option if necessary

[iamdanfox]

Before this PR

In baseline 3.52.0 we added this new plugin as a one-liner to add the --enable-preview flag wherever necessary (palantir/gradle-baseline#1549). We're using the extraProperties thing to avoid taking a compile dependency on baseline.

After this PR

==COMMIT_MSG==
sls-packaging will automatically include the --enable-preview jvm arg in launcher-static.yml if com.palantir.baseline-enable-preview-flag is applied.
==COMMIT_MSG==

Possible downsides?

[changelog-app]

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Type

• Feature
• Improvement
• Fix
• Break
• Deprecation
• Manual task
• Migration

Description

sls-packaging will automatically include the --enable-preview jvm arg in launcher-static.yml if com.palantir.baseline-enable-preview-flag is applied.

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[ferozco]

What do you think about keeping all of this inside of baseline? I think it might be a bit cleaner since consolidates the preview logic in one place and stays true to the nature of baseline configuring other plugins correctly

[iamdanfox]

Right, that's the other options for where to put this stuff. I wanted to preserve the situation we have now where there is no compilation dependency from sls-packaging to baseline or vice versa. It seems that if we put the logic in baseline and make it 'reach out' to configure sls-packaging then we'll need to have a compile dependency in order to get hold of the JavaServiceDistributionExtension.

I figured doing it this way round (with the Provider<Boolean>) avoid this kinda nicely? Also I figured that in theory there might be lots of different plugins that could all need to read this flag (e.g. maybe some gradle-graal things too??) so exposing a nice readable Provider from baseline seemed sort-of future-proof.

[iamdanfox]

Somewhat related thought - what do you think about baking something into our manifest or something so that we can do a papaya analysis and keep track of all the releases that enable this flag?? Feels like at some point we're going to want to keep an eye on who's using this!

EDIT nvm there's a dataset in papaya of launcher-static files already, so we can just detect the --enable-preview flag in that: ri.foundry.main.dataset.e3c4b54c-99eb-48cf-9f6d-df35d58e77bf

[svc-autorelease]

Released 4.22.0