Merge pull request #78 from modern-python/53-try-litestar-structlog-plugin

feat: integrate litestar StructlogPlugin for request.logger support

Author: lesnik512

docs/integrations/litestar.md

@@ -47,3 +47,17 @@ application = bootstrapper.bootstrap()
 ```
 
 Read more about available configuration options [here](../../../introduction/configuration):
+
+## Logging
+
+Structlog is integrated via Litestar's `StructlogPlugin`, which makes `request.logger` available in route handlers:
+
+```python
+from litestar import Request, get
+
+
+@get("/items")
+async def list_items(request: Request) -> list[str]:
+    request.logger.info("listing items")
+    return []
+```

docs/introduction/configuration.md

@@ -115,6 +115,21 @@ Additional parameters:
 - `logging_extra_processors`
 - `logging_unset_handlers`.
 
+### Structlog Litestar
+
+When using Litestar, the `StructlogPlugin` is automatically registered, which enables `request.logger` inside route handlers:
+
+```python
+from litestar import Litestar, Request, get
+from lite_bootstrap import LitestarConfig, LitestarBootstrapper
+
+
+@get("/")
+async def handler(request: Request) -> dict[str, str]:
+    request.logger.info("handling request")
+    return {"status": "ok"}
+```
+
 ### Structlog FastStream
 
 When using FastStream, the structlog logger is automatically injected into the broker so that all broker

lite_bootstrap/bootstrappers/litestar_bootstrapper.py

@@ -28,9 +28,11 @@
     import litestar
     from litestar.config.app import AppConfig
     from litestar.config.cors import CORSConfig
+    from litestar.logging.config import StructLoggingConfig
     from litestar.openapi import OpenAPIConfig
     from litestar.openapi.plugins import SwaggerRenderPlugin
     from litestar.plugins.prometheus import PrometheusConfig, PrometheusController
+    from litestar.plugins.structlog import StructlogConfig, StructlogPlugin
     from litestar.static_files import create_static_files_router
 
 if import_checker.is_litestar_opentelemetry_installed:
@@ -42,6 +44,9 @@
 if import_checker.is_opentelemetry_installed:
     from opentelemetry.trace import get_tracer_provider
 
+if import_checker.is_structlog_installed:
+    import structlog
+
 
 def build_span_name(method: str, route: str) -> str:
     if not route:
@@ -144,6 +149,25 @@ def bootstrap(self) -> None:
 class LitestarLoggingInstrument(LoggingInstrument):
     bootstrap_config: LitestarConfig
 
+    def bootstrap(self) -> None:
+        self._unset_handlers()
+        if import_checker.is_structlog_installed and import_checker.is_litestar_installed:
+            self.bootstrap_config.application_config.plugins.append(
+                StructlogPlugin(
+                    config=StructlogConfig(
+                        structlog_logging_config=StructLoggingConfig(
+                            processors=self.structlog_processors,
+                            logger_factory=self.memory_logger_factory,
+                            wrapper_class=structlog.stdlib.BoundLogger,
+                            cache_logger_on_first_use=True,
+                            pretty_print_tty=False,
+                            standard_lib_logging_config=None,
+                        ),
+                    ),
+                )
+            )
+            self._configure_foreign_loggers()
+
 
 @dataclasses.dataclass(kw_only=True, frozen=True)
 class LitestarOpenTelemetryInstrument(OpenTelemetryInstrument):

lite_bootstrap/instruments/logging_instrument.py

@@ -127,20 +127,28 @@ def _unset_handlers(self) -> None:
         for unset_handlers_logger in self.bootstrap_config.logging_unset_handlers:
             logging.getLogger(unset_handlers_logger).handlers = []
 
+    @property
+    def structlog_processors(self) -> list[typing.Any]:
+        return [
+            structlog.stdlib.filter_by_level,
+            *self.structlog_pre_chain_processors,
+            *self.bootstrap_config.logging_extra_processors,
+            structlog.processors.JSONRenderer(serializer=_serialize_log_with_orjson_to_string),
+        ]
+
+    @property
+    def memory_logger_factory(self) -> "MemoryLoggerFactory":
+        return MemoryLoggerFactory(
+            logging_buffer_capacity=self.bootstrap_config.logging_buffer_capacity,
+            logging_flush_level=self.bootstrap_config.logging_flush_level,
+            logging_log_level=self.bootstrap_config.logging_log_level,
+        )
+
     def _configure_structlog_loggers(self) -> None:
         structlog.configure(
-            processors=[
-                structlog.stdlib.filter_by_level,
-                *self.structlog_pre_chain_processors,
-                *self.bootstrap_config.logging_extra_processors,
-                structlog.processors.JSONRenderer(serializer=_serialize_log_with_orjson_to_string),
-            ],
+            processors=self.structlog_processors,
             context_class=dict,
-            logger_factory=MemoryLoggerFactory(
-                logging_buffer_capacity=self.bootstrap_config.logging_buffer_capacity,
-                logging_flush_level=self.bootstrap_config.logging_flush_level,
-                logging_log_level=self.bootstrap_config.logging_log_level,
-            ),
+            logger_factory=self.memory_logger_factory,
             wrapper_class=structlog.stdlib.BoundLogger,
             cache_logger_on_first_use=True,
         )

tests/test_litestar_bootstrap.py

@@ -112,6 +112,22 @@ async def get_item(item_id: int) -> dict[str, int]:
     assert any("GET /items/{item_id}" in name for name in span_names)
 
 
+def test_litestar_request_logger(litestar_config: LitestarConfig) -> None:
+    @litestar.get("/log-test")
+    async def log_handler(request: litestar.Request) -> dict[str, str]:
+        request.logger.info("test log from handler", key="value")
+        return {"status": "ok"}
+
+    config = dataclasses.replace(litestar_config, application_config=AppConfig(route_handlers=[log_handler]))
+    bootstrapper = LitestarBootstrapper(bootstrap_config=config)
+    application = bootstrapper.bootstrap()
+
+    with TestClient(app=application) as client:
+        response = client.get("/log-test")
+        assert response.status_code == status_codes.HTTP_200_OK
+        assert response.json() == {"status": "ok"}
+
+
 def test_build_span_name_no_route() -> None:
     assert build_span_name("GET", "") == "GET"