Preserve stored structlog exceptions in Sentry events

lite_bootstrap/instruments/logging_instrument.py

@@ -19,10 +19,6 @@ class _RenderedLine(str):
     __slots__ = ()
 
 
-def _mark_rendered(_: "WrappedLogger", __: str, rendered_line: str) -> _RenderedLine:
-    return _RenderedLine(rendered_line)
-
-
 if import_checker.is_structlog_installed:
     import structlog
 
@@ -141,12 +137,24 @@ def _build_excluded_paths(self) -> tuple[str, ...]:
 
     @property
     def structlog_processors(self) -> list[typing.Any]:
-        return [
-            structlog.stdlib.filter_by_level,
+        processors = [
             *self.structlog_pre_chain_processors,
             *self.bootstrap_config.logging_extra_processors,
-            structlog.processors.JSONRenderer(serializer=_serialize_log_to_string),
-            _mark_rendered,
+        ]
+        render_json = structlog.processors.JSONRenderer(serializer=_serialize_log_to_string)
+
+        def render_for_stdlib(
+            logger: "WrappedLogger", method: str, event_dict: "EventDict"
+        ) -> tuple[tuple[_RenderedLine], dict[str, typing.Any]]:
+            exc_info = event_dict.get("exc_info")
+            for processor in processors:
+                event_dict = processor(logger, method, event_dict)
+            line = _RenderedLine(render_json(logger, method, event_dict))
+            return (line,), {"exc_info": exc_info}
+
+        return [
+            structlog.stdlib.filter_by_level,
+            render_for_stdlib,
         ]
 
     def _configure_structlog_loggers(self) -> None:

tests/instruments/test_sentry_instrument.py

@@ -1,5 +1,6 @@
 import copy
 import dataclasses
+import json
 import logging
 import typing
 import uuid
@@ -556,3 +557,37 @@ def before_send(event: "sentry_types.Event", _: "sentry_types.Hint") -> "sentry_
     finally:
         logs.teardown()
         sentry.teardown()
+
+
+def test_structlog_stored_exception_reaches_sentry_and_stdout(
+    minimal_sentry_config: SentryConfig,
+    sentry_mock: SentryTestTransport,
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    sentry = SentryInstrument(bootstrap_config=minimal_sentry_config)
+    logs = LoggingInstrument(bootstrap_config=LoggingConfig())
+    sentry.bootstrap()
+    logs.bootstrap()
+    try:
+        try:
+            int("original stored error")
+        except ValueError as exc:
+            stored = exc
+
+        logger.error("stored exception", exc_info=stored, component="worker")
+
+        line = json.loads(capsys.readouterr().out.splitlines()[-1])
+        assert "Traceback (most recent call last)" in line["exception"]
+        assert "ValueError: invalid literal for int() with base 10: 'original stored error'" in line["exception"]
+        event = sentry_mock.mock_envelopes[0].get_event()
+        assert event is not None
+        (exception,) = event["exception"]["values"]
+        assert exception["type"] == "ValueError"
+        assert exception["value"] == "invalid literal for int() with base 10: 'original stored error'"
+        assert exception["stacktrace"]["frames"][-1]["function"] == (
+            "test_structlog_stored_exception_reaches_sentry_and_stdout"
+        )
+        assert event["contexts"]["structlog"] == {"component": "worker"}
+    finally:
+        logs.teardown()
+        sentry.teardown()