Add ability to install groups

[TheSuperiorStanislav]

Summary

Add the ability to specify which groups will be installed while making the main group as default one

Use Cases

When building for different environments like dev or prod. Would might need some dev tools, while prod is the opposite.

Closes #180

Checklist

• I have viewed, signed, and submitted the Contributor License Agreement.
• I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• I have added an integration test, if necessary.
• I have reviewed the styleguide for guidance on my code quality.
• I'm happy with the commit history on this PR (I have rebased/squashed as needed).

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: TheSuperiorStanislav / name: Stanislav Khlud (33a6e4f, 1514fda, e683b04)

[TheSuperiorStanislav]

@robdimsdale could you take a look? Pretty please)

[TheSuperiorStanislav]

@robdimsdale pinging one more time, because our team would like to have it

[TheSuperiorStanislav]

@robdimsdale Sorry for pinging, don't want this to go to waste. Could you take a look or ping somebody who could?

[dmikusa]

The PR seems OK to me. I am by no means a poetry expert, but what you're proposing sounds reasonable and it doesn't sound like it will change the existing or default behavior.

The PR is stuck because Github didn't run the tests for some reason. I don't know of a way to fix this, but if you just push up a new commit that should trigger the actions again and hopefully Github will run them this time. I haven't tried, but looks like you can push an empty commit to do this too. Anyway, give that a shot and let me know. I might need to approve them to be run too.

[TheSuperiorStanislav]

I guess I need approval

[TheSuperiorStanislav]

I guess I need approval

@dmikusa Sorry for ping, but i still need approval to run checks

[dmikusa]

I apologize @TheSuperiorStanislav. All I'm seeing is Waiting for status to be reported, which is something that happens when Github is just in a bad state. There's nothing to approve, it's just stuck. Not sure if this happened cause it timed out or if something just failed to run the jobs. Can you try updating the PR one more time? Just push anything, and it should trigger the PR again. Then ping me on Slack and I'll take a look right away. Apologizes, again. We'll get this sorted.

[dmikusa]

@paketo-buildpacks/python-maintainers Any thoughts on this PR? The issue seems to have quite a few up-votes from the community. Be nice to get something to support this. Thanks

[jericop]

Thanks for the nudge and apologies for not getting around to looking at this sooner. This is definitely a welcome change, so thanks for this contribution! The PR looks good.

I know the current behavior is to install all dependencies in pyproject.toml, which is not always desired when there are dev dependencies. In my experience most poetry users follow the docs, so I think making this the default should be acceptable. While there is a chance that some users may rely on dev dependencies at run time, this change will encourage recommended configurations in pyproject.toml. I would consider this a minor server change at minimum, but not sure if this warrants a major bump. Any thoughts @dmikusa?

[dmikusa]

I think the intent of Paketo buildpacks has always been to produce production ready containers & this sounds like a way to improve that, so 👍 from me.

It's still a 0.x buildpack, so I would suggest that we bump the minor version to 0.4 and make a note of this behavior change in the release notes & also in the documentation.

https://paketo.io/docs/howto/python/#poetry

Maybe check the samples too, make sure this doesn't break any of them.