Created strongly typed PolicyMatch struct from policy config to match values

[andriusluk]

What this PR does:
Introduced AttributePolicyMatch & IntrinsicPolicyMatch structures to match span attributes based on strongly typed values & precompiled regex which are used to match span attribute values.

Which issue(s) this PR fixes:
Fixes #3015

Checklist

• Tests updated
• Documentation added
• CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX]

[CLAassistant]

All committers have signed the CLA.

[joe-elliott]

thx for the improvements!

as far as i can tell there should be no change to a user's config correct? the old config will parse and work just fine?

this seems like it would result in some nice perf improvements. dropping the reflection and only doing the regex once. if you had time for benchmarks that would be cool, but no worries if you're busy.

i have one suggestion regarding the interface. i think it would help me see the structure of code better. do you think it makes sense?

[zalegrala]

This looks like a nice change to me, good work. Thanks for the PR.

[andriusluk]

@joe-elliott tempodb tests seem to be timing out for some reason. I see the same timeout on the other PRs as well.

=== Failed
=== FAIL: tempodb  (0.00s)
panic: test timed out after 20m0s
...

[joe-elliott]

It's looking good. I think the code in attribute.go/intrinsic.go is much more straightforward with your changes.

Looking for some cleanup in splitpolicy.go. Other than that I think this is good to go. Given how we much we rely on this feature I will run it in some on some of our internal clusters after the next round of changes. If everything is looking good then I think this will be ready.

[joe-elliott]

@joe-elliott tempodb tests seem to be timing out for some reason. I see the same timeout on the other PRs as well.

Yup, this times out occasionally regularly. Don't worry about it. I will re-run in CI that is unrelated to your PR.

[joe-elliott]

You've gotten this PR into a really nice spot. Code is clear and I love the benchmarks.

I'm going to approve, but not merge just yet to give some maintainers with more experience in this area a chance to review.

[joe-elliott]

Thanks for the contribution! I think everyone will enjoy the more performant filters.