fix: enable uvicorn log propagation to root structured handler

- propagate=False with cleared handlers silently swallowed all uvicorn
  error/startup messages — set propagate=True so they reach the root
  structlog JSON handler
- document uvicorn integration: programmatic usage requires
  log_config=None and access_log=False; CLI usage self-heals via
  module import order
- remove duplicate dead assignment in AccessLogMiddleware.__init__

Author: babs

README.md

@@ -22,6 +22,8 @@ app.add_middleware(fastapi_structured_logging.AccessLogMiddleware)
 
 ```
 
+> **Important:** When using `uvicorn.run()`, pass `log_config=None` and `access_log=False` to prevent uvicorn from re-adding its default plain-text handlers over the structured logging setup. When using the uvicorn CLI, this is not needed — `setup_logging()` runs during app import, after uvicorn's logging init. Pass `--no-access-log` to let the middleware handle access logs.
+
 ## Configuration Options
 
 The library provides extensive configuration options to customize logging and access logging behavior.

examples/README.md

@@ -55,7 +55,7 @@ app.add_middleware(fastapi_structured_logging.AccessLogMiddleware)
 Run the FastAPI application with OpenTelemetry instrumentation:
 
 ```bash
-uv run opentelemetry-instrument uvicorn example1:app
+uv run opentelemetry-instrument uvicorn example1:app --no-access-log
 ```
 
 The server will start on `http://0.0.0.0:8000`.

examples/example1.py

@@ -31,4 +31,4 @@ def hello(who: str):
 
 
 if __name__ == "__main__":
-    uvicorn.run(app, host="0.0.0.0", port=8000)
+    uvicorn.run(app, host="0.0.0.0", port=8000, log_config=None, access_log=False)

src/fastapi_structured_logging.py

@@ -109,10 +109,12 @@ def setup_logging(json_logs: Optional[bool] = None, log_level: str = "INFO"):
     root_logger = logging.getLogger()
     root_logger.addHandler(handler)
     root_logger.setLevel(log_level.upper())
-    # Adjust Uvicorn loggers to propagate to root logger properly.
+    # Clear uvicorn's default handlers (plain-text) and let errors propagate
+    # to the root JSON handler. Access stays disabled — AccessLogMiddleware
+    # handles it via structured logging instead.
     for log_name in ["uvicorn", "uvicorn.error"]:
         logging.getLogger(log_name).handlers.clear()
-        logging.getLogger(log_name).propagate = False
+        logging.getLogger(log_name).propagate = True
     logging.getLogger("uvicorn.access").handlers.clear()
     logging.getLogger("uvicorn.access").propagate = False
 
@@ -177,7 +179,6 @@ def __init__(self, app: ASGIApp, config: Optional[AccessLogConfig] = None):
             ]
         except ValueError:
             self._cache_trusted_proxy_networks = []
-            self._cache_trusted_proxy_networks = []
 
     def __is_trusted_proxy(self, ip: str) -> bool:
         """Check if the given IP is in the trusted proxy CIDR ranges."""