chore: introduce APM_TRACING RC product

[P403n1x87]

We refactor the APM_TRACING remote configuration product that allows dispatching remote configuration to the library for remote enablement/configuration of library components and features. Firstly, we make this an actual product, in the sense of the product protocol. We then extend the latter to modularise capabilities and remote APM configuration handling.

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/internal/remoteconfig/products/__init__.py                      @DataDog/remote-config @DataDog/apm-core-python
ddtrace/internal/remoteconfig/products/apm_tracing.py                   @DataDog/remote-config @DataDog/apm-core-python
ddtrace/_trace/product.py                                               @DataDog/apm-sdk-api-python
ddtrace/internal/README.md                                              @DataDog/python-guild @DataDog/apm-core-python
ddtrace/settings/_config.py                                             @DataDog/apm-core-python
pyproject.toml                                                          @DataDog/python-guild
riotfile.py                                                             @DataDog/apm-python
tests/integration/test_settings.py                                      @DataDog/apm-core-python
tests/internal/test_settings.py                                         @DataDog/apm-core-python
ddtrace/internal/remoteconfig/products/client.py                        @DataDog/remote-config @DataDog/apm-core-python

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: chore/apm-tracing-rc
Commit report: 7c4ca59
Test service: dd-trace-py

✅ 0 Failed, 130 Passed, 1468 Skipped, 4m 50.35s Total duration (35m 10.03s time saved)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-04-02 12:15:44

Comparing candidate commit 76de753 in PR branch chore/apm-tracing-rc with baseline commit 5b3a8f2 in branch main.

Found 2 performance improvements and 0 performance regressions! Performance is the same for 496 metrics, 2 unstable metrics.

scenario:iast_aspects-ospathbasename_aspect

• 🟩 execution_time [-495.560ns; -439.787ns] or [-13.280%; -11.786%]

scenario:iast_aspects-ospathdirname_aspect

• 🟩 execution_time [-362.416ns; -305.018ns] or [-8.900%; -7.491%]

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: chore/apm-tracing-rc
Commit report: c6ce9ed
Test service: dd-trace-py

✅ 0 Failed, 43 Passed, 290 Skipped, 53.52s Total duration (5m 2.68s time saved)

[shatzi]

I think we should also record the right capabilities once they set.

[mabdinur]

Benchmarks

Benchmark execution time: 2025-03-06 17:07:38

Comparing candidate commit 89b3d7e in PR branch chore/apm-tracing-rc with baseline commit 63c1237 in branch main.

Found 0 performance improvements and 9 performance regressions! Performance is the same for 451 metrics, 2 unstable metrics.

scenario:startup-ddtrace_run

• 🟥 execution_time [+109.758ms; +111.183ms] or [+10.931%; +11.073%]

scenario:startup-ddtrace_run_django

• 🟥 execution_time [+132.938ms; +134.796ms] or [+11.895%; +12.061%]

scenario:startup-ddtrace_run_flask

• 🟥 execution_time [+125.581ms; +127.328ms] or [+10.802%; +10.953%]

scenario:startup-ddtrace_run_import_ddtrace_auto

• 🟥 execution_time [+109.066ms; +110.516ms] or [+10.866%; +11.010%]

scenario:startup-ddtrace_run_import_ddtrace_auto_django

• 🟥 execution_time [+134.688ms; +136.274ms] or [+12.057%; +12.199%]

scenario:startup-ddtrace_run_import_ddtrace_auto_flask

• 🟥 execution_time [+126.786ms; +128.407ms] or [+10.906%; +11.045%]

scenario:startup-import_ddtrace_auto

• 🟥 execution_time [+109.915ms; +111.070ms] or [+16.861%; +17.038%]

scenario:startup-import_ddtrace_auto_django

• 🟥 execution_time [+126.351ms; +127.887ms] or [+16.331%; +16.529%]

scenario:startup-import_ddtrace_auto_flask

• 🟥 execution_time [+126.095ms; +127.408ms] or [+15.585%; +15.747%]

The new plugin interface increases start up time by over 10%. Can we try to optimize this? This seems like a blocker

[mabdinur]

left a comment about the overhead of this new API

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 244 ± 8 ms.

The average import time from base is: 247 ± 8 ms.

The import time difference between this PR and base is: -3.2 ± 0.3 ms.

Import time breakdown

The following import paths have grown:

ddtrace.auto 0.812 ms (0.33%)

ddtrace.bootstrap.sitecustomize 0.719 ms (0.29%)

ddtrace.bootstrap.preload 0.447 ms (0.18%)

ddtrace.internal.products 0.184 ms (0.08%)

ddtrace.settings.dynamic_instrumentation 0.109 ms (0.04%)

multiprocessing 0.074 ms (0.03%)

multiprocessing.context 0.074 ms (0.03%)

multiprocessing.process 0.074 ms (0.03%)

ddtrace.settings.crashtracker 0.105 ms (0.04%)

ddtrace.internal.flare.flare 0.086 ms (0.04%)

logging.handlers 0.086 ms (0.04%)

ddtrace.settings.profiling 0.073 ms (0.03%)

ddtrace.vendor.psutil 0.073 ms (0.03%)

ddtrace.vendor.psutil._pslinux 0.073 ms (0.03%)

glob 0.073 ms (0.03%)

ddtrace.appsec._common_module_patches 0.109 ms (0.04%)

ddtrace.appsec._asm_request_context 0.109 ms (0.04%)

shlex 0.101 ms (0.04%)

ddtrace._trace.trace_handlers 0.061 ms (0.03%)

ddtrace._trace._inferred_proxy 0.061 ms (0.03%)

ddtrace 0.094 ms (0.04%)

ddtrace.settings._config 0.094 ms (0.04%)

ddtrace.internal.gitmetadata 0.094 ms (0.04%)

ddtrace.ext.ci 0.094 ms (0.04%)

The following import paths have shrunk:

ddtrace.auto 2.329 ms (0.96%)

ddtrace.bootstrap.sitecustomize 1.498 ms (0.61%)

ddtrace.bootstrap.preload 1.237 ms (0.51%)

ddtrace.internal.products 0.801 ms (0.33%)

ddtrace.internal.remoteconfig.client 0.653 ms (0.27%)

multiprocessing 0.149 ms (0.06%)

multiprocessing.context 0.103 ms (0.04%)

ddtrace.appsec._remoteconfiguration 0.134 ms (0.06%)

ddtrace.appsec._capabilities 0.134 ms (0.06%)

ddtrace.settings.crashtracker 0.124 ms (0.05%)

ddtrace.internal.datadog.profiling.crashtracker 0.124 ms (0.05%)

ddtrace.internal.datadog.profiling.crashtracker._crashtracker 0.124 ms (0.05%)

ddtrace.internal.datadog.profiling._types 0.124 ms (0.05%)

ddtrace.settings.profiling 0.103 ms (0.04%)

ddtrace.vendor.psutil 0.103 ms (0.04%)

ddtrace.internal.flare.flare 0.075 ms (0.03%)

ddtrace.internal.flare 0.075 ms (0.03%)

ddtrace._trace.trace_handlers 0.154 ms (0.06%)

ddtrace.appsec._common_module_patches 0.106 ms (0.04%)

ddtrace.appsec._asm_request_context 0.106 ms (0.04%)

ddtrace.appsec._utils 0.106 ms (0.04%)

ddtrace 0.832 ms (0.34%)

ddtrace.settings._config 0.111 ms (0.05%)

ddtrace.internal.gitmetadata 0.111 ms (0.05%)