Make results' limits configurable (fixes #347)

[sskorol]

Context

There were several places in code with hardcoded limits for items rendered on charts. It was really inconvenient for the end-user who had to rebuild the entire project to make limits configurable.

This fix moves the actual configuration into an Aggregator interface which is implemented by key plugins. Moreover, a user can now control the limits via ALLURE_RESULTS_LIMIT env variable that could be set before the report's generation. Note that a newly added method was intentionally made static as some of the APIs that adjust the limits are also static.

Fixes #347

Checklist

• Sign Allure CLA
• Provide unit tests

[indradeepchowdhury]

Hello, Just checking to see if there is a possibility of this PR to get merged soon and what it would take to get this merged :)

Thank you.

[indradeepchowdhury]

LGTM!

[sskorol]

@indradeepchowdhury as far as I remember, @baev had some concerns in terms of implementation. Need to double-check with him.

[indradeepchowdhury]

@indradeepchowdhury as far as I remember, @baev had some concerns in terms of implementation. Need to double-check with him.

Thanks for the update @sskorol. @baev would it be possible to expedite this feature. This would be a super cool feature to have.

[pbandura]

Hi @sskorol. Thanks for jour work on providing such feature.
I've got one question - do you still work on this or has it been parked?

[sskorol]

Hi @pbandura, I don't. When I initially pushed it, it was a fully working feature. I talked to maintainers directly. And they promised to check. Seems like they didn't have time. Now I see there's a conflict. I can resolve it. And then you will be able to build a new version with this feature from sources if it's important for you.

[indradeepchowdhury]

Hi @sskorol I think this feature would be pretty cool and I am looking forward to using it. This feature will allow us to align the history with our Sprint duration or even let us increase the history limit to a month for proper tracking 🙂

[sskorol]

@indradeepchowdhury @pbandura force-pushed changes with conflicts' resolution. Now you can build the report on your own with this feature.

[sangheee]

@sskorol @indradeepchowdhury @baev Why didn't you guys apply this?

[baev]

I don't like the current implementation because:

1. Plugin API changes -- new method introduced in Aggregator interface may create some issues for other users
2. The env variable processing is unsafe -- You can set negative or non-number env variable and crash your report generation
3. There are no tests provided

Besides that, our team is heavily focused on Allure 3 development right now, so this change isn't really in priority right now

[A1exKH]

Code LGTM.

Please resolve conflicts for this PR.