feat(tracing): report OTLP export status in startup diagnostic log

Add three boolean fields to the tracer's startup diagnostic log
("DATADOG TRACER CONFIGURATION") indicating whether each telemetry
signal is exported over OTLP:

- otlp_traces_export_enabled: reflects agent_config.trace_otlp_export_enabled
  (opt-in via OTEL_TRACES_EXPORTER=otlp; export is routed through
  libdatadog's native OTLP trace exporter)
- otlp_metrics_export_enabled: reflects config._otel_metrics_enabled
- otlp_logs_export_enabled: reflects config._otel_logs_enabled

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: bm1549

ddtrace/internal/debug.py

@@ -130,6 +130,9 @@ def collect() -> dict[str, Any]:
         log_injection_enabled=ddtrace.config._logs_injection,
         health_metrics_enabled=ddtrace.config._health_metrics_enabled,
         runtime_metrics_enabled=RuntimeWorker.enabled,
+        otlp_traces_export_enabled=agent_config.trace_otlp_export_enabled,
+        otlp_metrics_export_enabled=ddtrace.config._otel_metrics_enabled,
+        otlp_logs_export_enabled=ddtrace.config._otel_logs_enabled,
         dd_version=ddtrace.config.version or "",
         global_tags=tags_to_str(ddtrace.config.tags),
         tracer_tags=tags_to_str(tracer._tags),

releasenotes/notes/otlp-export-startup-log-2a93c575ab280413.yaml

@@ -0,0 +1,6 @@
+---
+other:
+  - |
+    tracing: The startup configuration log now reports ``otlp_traces_export_enabled``,
+    ``otlp_metrics_export_enabled``, and ``otlp_logs_export_enabled``, indicating whether
+    OTLP export is enabled for traces, metrics, and logs respectively.

tests/integration/test_debug.py

@@ -83,6 +83,12 @@ def test_standard_tags():
     assert f.get("log_injection_enabled") is True
     assert f.get("health_metrics_enabled") is False
     assert f.get("runtime_metrics_enabled") is False
+    assert "otlp_traces_export_enabled" in f
+    assert "otlp_metrics_export_enabled" in f
+    assert "otlp_logs_export_enabled" in f
+    assert isinstance(f.get("otlp_traces_export_enabled"), bool)
+    assert isinstance(f.get("otlp_metrics_export_enabled"), bool)
+    assert isinstance(f.get("otlp_logs_export_enabled"), bool)
     assert f.get("sampling_rules") == []
     assert f.get("global_tags") == ""
     assert f.get("tracer_tags") == ""
@@ -239,6 +245,52 @@ def test_runtime_metrics_enabled_via_env_var_start():
     )
 
 
+@pytest.mark.subprocess(
+    env=dict(
+        # Clear any inherited OTLP-related env so the defaults are deterministic.
+        OTEL_SDK_DISABLED=None,
+        OTEL_TRACES_EXPORTER=None,
+        OTEL_METRICS_EXPORTER=None,
+        OTEL_LOGS_EXPORTER=None,
+        DD_TRACE_OTEL_ENABLED=None,
+        DD_METRICS_OTEL_ENABLED=None,
+        DD_LOGS_OTEL_ENABLED=None,
+    )
+)
+def test_otlp_export_enabled_fields_default():
+    from ddtrace.internal import debug
+
+    f = debug.collect()
+
+    assert f.get("otlp_traces_export_enabled") is False
+    assert f.get("otlp_metrics_export_enabled") is False
+    assert f.get("otlp_logs_export_enabled") is False
+
+
+@pytest.mark.subprocess(
+    env=dict(
+        # trace_otlp_export_enabled is derived at config init, so it must come from the
+        # environment; DD_TRACE_AGENT_PROTOCOL_VERSION is cleared because it disables OTLP.
+        OTEL_TRACES_EXPORTER="otlp",
+        DD_TRACE_AGENT_PROTOCOL_VERSION=None,
+    ),
+    err=None,
+)
+def test_otlp_export_enabled_fields_set():
+    import ddtrace
+    from ddtrace.internal import debug
+
+    # Metrics/logs are read live from the global config, so they can be toggled here.
+    ddtrace.config._otel_metrics_enabled = True
+    ddtrace.config._otel_logs_enabled = True
+
+    f = debug.collect()
+
+    assert f.get("otlp_traces_export_enabled") is True
+    assert f.get("otlp_metrics_export_enabled") is True
+    assert f.get("otlp_logs_export_enabled") is True
+
+
 def test_to_json():
     info = debug.collect()
     json.dumps(info)