feat(onboarding): early exit conditions in lib-injection [backport 2.9]

[emmettbutler]

This pull request adds "guardrails" to the "library injection" process. These are early exit conditions from the instrumentation process intended to avoid sending any traces when undefined behavior is likely. The code makes this determination on the basis of software versions present in the application environment, both of Python packages and the Python runtime itself.

The biggest risk here is that instrumentation is disabled when it's not intended to be. I think existing tests in tests/lib-injection cover this pretty well. There's a new test added that verifies instrumentation was cancelled when an unsupported package version is present.

Contains changes from #9418 Related RFC: "[RFC] One Step Guardrails"

• minimum package version checks

• Testing

• replace envvars with inject_force

• figure out what to use instead of pkg_resources

• replace local file path with DD_TELEMETRY_FORWARDER_PATH

• Change(s) are motivated and described in the PR description

• Testing strategy is described if automated tests are not included in the PR

• Risks are described (performance impact, potential for breakage, maintainability)

• Change is maintainable (easy to change, telemetry, documentation)

• Library release note guidelines are followed or label changelog/no-changelog is set

• Documentation is included (in-code, generated user docs, public corp docs)

• Backport labels are set (if applicable)

• If this PR changes the public interface, I've notified @DataDog/apm-tees.

• Title is accurate

• All changes are related to the pull request's stated goal

• Description motivates each change

• Avoids breaking API changes

• Testing strategy adequately addresses listed risks

• Change is maintainable (easy to change, telemetry, documentation)

• Release note makes sense to a user of the library

• 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

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: backport-9323-to-2.9
Commit report: d4db6ef
Test service: dd-trace-py

❌ 1 Failed (0 Known Flaky), 160353 Passed, 15474 Skipped, 8h 58m 36.28s Total duration (2h 1m 12.31s time saved)
⌛ 11 Performance Regressions

❌ Failed Tests (1)

• test_load_new_empty_config_and_remove_targets_file_same_product - test_remoteconfiguration.py - Details

  Expand for error

   expected call not found.
   Expected: _appsec_rules_data({'asm': {'enabled': <tests.appsec.utils.Either object at 0x7f4e9817ba30>}, 'data': [{'x': 1}], 'data2': [{'y': 2}]}, None)
   Actual: _appsec_rules_data({'data': [{'x': 1}], 'data2': [{'y': 2}]}, None)
  

⌛ Performance Regressions vs Default Branch (11)

This report shows up to 5 performance regressions.

• test_unspecified_operation_name_schematization_v1 - test_tornado_web.py 4.07s (+3.35s, +463%) - Details
• test_unspecified_service_name_schematization_v0 - test_tornado_web.py 3.82s (+3.1s, +432%) - Details
• test_service_name_schematization_default - test_tornado_web.py 3.89s (+3.17s, +441%) - Details
• test_service_name_schematization_v1 - test_tornado_web.py 3.76s (+3.04s, +422%) - Details
• test_unspecified_service_name_schematization_default - test_tornado_web.py 3.82s (+3.1s, +432%) - Details

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 10.15%. Comparing base (acd1bf5) to head (d4db6ef).
Report is 7 commits behind head on 2.9.

Additional details and impacted files

@@            Coverage Diff             @@
##              2.9   #10563      +/-   ##
==========================================
- Coverage   10.22%   10.15%   -0.07%     
==========================================
  Files        1258     1258              
  Lines      120899   120919      +20     
==========================================
- Hits        12356    12281      -75     
- Misses     108543   108638      +95     

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[pr-commenter]

Benchmarks

Benchmark execution time: 2024-09-09 15:48:24

Comparing candidate commit ea3ee4e in PR branch backport-9323-to-2.9 with baseline commit f20d79c in branch 2.9.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 209 metrics, 9 unstable metrics.