chore(logger): disable native logging by default (#15005)

## Description

Disable native logging by default as it shouldn't be logging to file by
default.

## Testing

<!-- Describe your testing strategy or note what tests are included -->

## Risks

<!-- Note any risks associated with this change, or "None" if no risks
-->

## Additional Notes

<!-- Any other information that would be helpful for reviewers -->

---------

Co-authored-by: Munir Abdinur <munir.abdinur@datadoghq.com>

Author: VianneyRuhlmann

ddtrace/_logger.py

@@ -131,7 +131,9 @@ def _configure_ddtrace_native_logger():
         from .settings._config import config
 
         if config._trace_writer_native:
-            backend = get_config("_DD_NATIVE_LOGGING_BACKEND", "file", report_telemetry=True)
+            backend = get_config("_DD_NATIVE_LOGGING_BACKEND")
+            if not backend:
+                return
             kwargs = {"output": backend}
             if backend == "file":
                 kwargs["path"] = get_config("_DD_NATIVE_LOGGING_FILE_PATH", "native.log", report_telemetry=True)

tests/tracer/test_native_logger.py

@@ -68,7 +68,7 @@ def test_logger_configure(output, path, files, max_bytes):
 cases = [(config, msg, LEVELS.index(msg) >= LEVELS.index(config)) for config in LEVELS for msg in LEVELS]
 
 
-@pytest.mark.parametrize("backend", ["stdout", "stderr", "file"])
+@pytest.mark.parametrize("backend", ["", "stdout", "stderr", "file"])
 @pytest.mark.parametrize("configured_level, message_level, should_log", cases)
 def test_logger_subprocess(
     backend, configured_level, message_level, should_log, tmp_path, ddtrace_run_python_code_in_subprocess
@@ -93,7 +93,11 @@ def test_logger_subprocess(
     out, err, status, _ = ddtrace_run_python_code_in_subprocess(code, env=env)
 
     assert status == 0
-    if backend == "stdout":
+    if backend == "":
+        assert out == b""
+        assert err == b""
+        assert not log_path.exists()
+    elif backend == "stdout":
         found = message in out.decode("utf8")
         assert err == b""
         assert found == should_log