chore: configurable logger levels

[P403n1x87]

We introduce private enviornment variables that allow configuring the log level of the ddtrace loggers. This allows for fine-grained control over the logger levels, making debugging easier by reducing the noise of logs. For example, setting _DD_DEBUGGING_LOG_LEVEL=DEBUG would enable debug logs for any loggers under ddtrace.debugging only.

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/logger.py                                              @DataDog/apm-core-python
tests/tracer/test_logger.py                                             @DataDog/apm-sdk-api-python

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 279 ± 6 ms.

The average import time from base is: 281 ± 7 ms.

The import time difference between this PR and base is: -1.7 ± 0.3 ms.

Import time breakdown

The following import paths have appeared:

ddtrace.auto 7.188 ms (2.57%)

ddtrace 7.188 ms (2.57%)

ddtrace._logger 7.188 ms (2.57%)

ddtrace.internal.telemetry 7.188 ms (2.57%)

ddtrace.internal.logger 7.188 ms (2.57%)

dataclasses 7.188 ms (2.57%)

inspect 6.354 ms (2.27%)

ast 2.317 ms (0.83%)

_ast 1.202 ms (0.43%)

dis 1.469 ms (0.53%)

opcode 0.588 ms (0.21%)

_opcode 0.160 ms (0.06%)

importlib.machinery 0.235 ms (0.08%)

importlib 0.173 ms (0.06%)

copy 0.198 ms (0.07%)

The following import paths have disappeared:

ddtrace.auto 7.706 ms (2.76%)

ddtrace 7.706 ms (2.76%)

ddtrace._logger 7.706 ms (2.76%)

ddtrace.internal.telemetry 7.706 ms (2.76%)

ddtrace.settings._agent 7.706 ms (2.76%)

ddtrace.settings 7.706 ms (2.76%)

ddtrace.settings.http 7.510 ms (2.69%)

ddtrace.internal.utils.cache 6.869 ms (2.46%)

inspect 6.869 ms (2.46%)

ast 2.349 ms (0.84%)

_ast 1.211 ms (0.43%)

dis 1.480 ms (0.53%)

opcode 0.605 ms (0.22%)

_opcode 0.165 ms (0.06%)

importlib.machinery 0.232 ms (0.08%)

importlib 0.170 ms (0.06%)

ddtrace.internal.utils.http 0.641 ms (0.23%)

dataclasses 0.641 ms (0.23%)

ddtrace._hooks 0.196 ms (0.07%)

copy 0.196 ms (0.07%)

The following import paths have grown:

ddtrace.auto 1.581 ms (0.57%)

ddtrace 1.581 ms (0.57%)

ddtrace._logger 1.581 ms (0.57%)

ddtrace.internal.telemetry 1.581 ms (0.57%)

ddtrace.internal.logger 0.909 ms (0.33%)

ddtrace.internal.utils.formats 0.586 ms (0.21%)

ddtrace.internal.compat 0.586 ms (0.21%)

pathlib 0.586 ms (0.21%)

ddtrace.settings._agent 0.086 ms (0.03%)

ddtrace.settings 0.086 ms (0.03%)

ddtrace.settings.http 0.086 ms (0.03%)

ddtrace.internal.utils.http 0.086 ms (0.03%)

email.encoders 0.086 ms (0.03%)

base64 0.086 ms (0.03%)

struct 0.086 ms (0.03%)

_struct 0.086 ms (0.03%)

The following import paths have shrunk:

ddtrace.auto 2.445 ms (0.87%)

ddtrace.bootstrap.sitecustomize 1.373 ms (0.49%)

ddtrace.bootstrap.preload 1.373 ms (0.49%)

ddtrace.internal.remoteconfig.client 0.649 ms (0.23%)

ddtrace 1.072 ms (0.38%)

ddtrace._logger 0.387 ms (0.14%)

ddtrace.internal.telemetry 0.387 ms (0.14%)

ddtrace.settings._agent 0.248 ms (0.09%)

ddtrace.settings 0.248 ms (0.09%)

ddtrace.settings.http 0.248 ms (0.09%)

ddtrace.internal.utils.http 0.248 ms (0.09%)

email.encoders 0.088 ms (0.03%)

base64 0.072 ms (0.03%)

email 0.016 ms (0.01%)

ddtrace.internal.utils.formats 0.139 ms (0.05%)

ddtrace.internal.compat 0.139 ms (0.05%)

ddtrace.internal._unpatched 0.034 ms (0.01%)

json 0.034 ms (0.01%)

json.decoder 0.034 ms (0.01%)

re 0.034 ms (0.01%)

enum 0.034 ms (0.01%)

types 0.034 ms (0.01%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-06-12 17:01:51

Comparing candidate commit e9ae14d in PR branch chore/ddtrace-logger-level with baseline commit 140c2b9 in branch main.

Found 0 performance improvements and 1 performance regressions! Performance is the same for 555 metrics, 6 unstable metrics.

scenario:iastaspectsospath-ospathsplitdrive_aspect

• 🟥 execution_time [+356.703ns; +424.484ns] or [+9.750%; +11.603%]

[brettlangdon]

tests?

[P403n1x87]

tests?

I can add them if we're all onboard with merging this change 🙂

[brettlangdon]

we shouldn't have to manually set the level for all children.... right?

meaning _DD_TESTING_DEBUG_LOG_LEVEL=DEBUG should only set the level on testing.debug only, and not on .foo or .foo.bar.

You should evaluate via .isEnabledFor(logging.DEBUG) instead of .level == logging.DEBUG, since that takes into account it's parents settings as well:

>>> a = logging.getLogger("a")
>>> b = logging.getLogger("a.b")
>>> a.setLevel(logging.DEBUG)
>>> b.isEnabledFor(logging.DEBUG)
True
>>> a.setLevel(logging.ERROR)
>>> b.isEnabledFor(logging.DEBUG)
False

[P403n1x87]

Ah that's a good point, but what if the logger for a is never created? 🤔

[emmettbutler]

This makes sense to me