chore(tracer): core additions

[christophe-papazian]

Small core additions:

• get_root to get the root context
• discard_item to discard items
• remove traverse optional argument of get_item and split the method and function in two version, get_item and get_local_item for efficiency reasons.
• use modern type annotations
• set _CURRENT_CONTEXT directly (without using an ephemeral None value that breaks type checking)
• add asyncio test for all of that with concurrent threads

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[github-actions]

CODEOWNERS have been resolved as:

ddtrace/_trace/trace_handlers.py                                        @DataDog/apm-sdk-api-python
ddtrace/appsec/_iast/processor.py                                       @DataDog/asm-python
ddtrace/internal/core/__init__.py                                       @DataDog/apm-core-python
tests/internal/test_context_events_api.py                               @DataDog/apm-core-python

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-09-20 15:23:13

Comparing candidate commit bc44c35 in PR branch christophe-papazian/core_additions with baseline commit baac738 in branch main.

Found 1 performance improvements and 0 performance regressions! Performance is the same for 295 metrics, 48 unstable metrics.

scenario:iast_aspects-aspect_iast_do_index_on_dict

• 🟩 max_rss_usage [-2.597MB; -2.254MB] or [-8.744%; -7.590%]

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: christophe-papazian/core_additions
Commit report: bc44c35
Test service: dd-trace-py

✅ 0 Failed, 592 Passed, 694 Skipped, 19m 24.51s Total duration (17m 58.39s time saved)