Bug: StructlogPlugin loggers do not adhere to set log level

[JacobCoffee]

Description

The expectation is that any logging done is derivative of the root logger if not otherwise specified.

Perhaps I've done this wrong - but I don't want to see debug level logs when I have set the level to INFO/20 or above.

URL to code causing the issue

No response

MCVE

import logging

import structlog
from litestar import Litestar, get
from litestar.plugins.structlog import StructlogPlugin
from litestar.logging import LoggingConfig, StructLoggingConfig
from litestar.middleware.logging import LoggingMiddlewareConfig
from litestar.plugins.structlog import StructlogConfig

logging_config = StructlogConfig(
    structlog_logging_config=StructLoggingConfig(
        log_exceptions="always",
        traceback_line_limit=4,
        standard_lib_logging_config=LoggingConfig(
            root={"level": logging.getLevelName(20), "handlers": ["queue_listener"]},
            loggers={
                "uvicorn.access": {
                    "propagate": False,
                    "level": 30,
                    "handlers": ["queue_listener"],
                },
                "uvicorn.error": {
                    "propagate": False,
                    "level": 20,
                    "handlers": ["queue_listener"],
                },
            },
        ),
    ),
    middleware_logging_config=LoggingMiddlewareConfig(
        request_log_fields=["method", "path", "path_params", "query"],
        response_log_fields=["status_code"],
    ),
)

logger = structlog.get_logger()

@get("/")
async def foo() -> None:
    logger.debug("you shouldnt see this")
    pass


structlog = StructlogPlugin(config=logging_config)
app = Litestar(route_handlers=[foo], plugins=[structlog])

Steps to reproduce

1. Create and run app: `litestar --app asgi:app run`
2. `curl 0.0.0.0:8000`
3. See error

2024-04-23T22:43:18.589449Z [debug    ] you shouldnt see this         
INFO:     127.0.0.1:58488 - "GET / HTTP/1.1" 200 OK

Screenshots

No response

Logs

✗ litestar --app asgi:app run
Using Litestar app from env: 'asgi:app'
Starting server process ────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
┌──────────────────────────────┬──────────────────────┐
│ Litestar version             │ 2.8.2                │
│ Debug mode                   │ Disabled             │
│ Python Debugger on exception │ Disabled             │
│ CORS                         │ Disabled             │
│ CSRF                         │ Disabled             │
│ OpenAPI                      │ Enabled path=/schema │
│ Compression                  │ Disabled             │
│ Middlewares                  │ LoggingMiddleware    │
└──────────────────────────────┴──────────────────────┘
2024-04-23T22:43:18.589367Z [info     ] HTTP Request                   method=GET path=/ path_params={} query={}
2024-04-23T22:43:18.589449Z [debug    ] you shouldnt see this         
INFO:     127.0.0.1:58488 - "GET / HTTP/1.1" 200 OK
2024-04-23T22:43:18.589767Z [info     ] HTTP Response                  status_code=200

Litestar Version

main

Platform

• Linux
• Mac
• Windows
• Other (Please specify in the description above)

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[JacobCoffee]

If i blanketly set it works, so maybe something with set_level?

import logging
import structlog

structlog.configure(
    wrapper_class=structlog.make_filtering_bound_logger(logging.INFO),
)

[peterschutt]

Issue is that the logs emitted via structlog's loggers don't pass through the standard library logging. This is why they aren't filtered by the level set on the root logger object, they are getting emitted directly to stdout via structlog.

As @JacobCoffee noted above, this can be addressed by:

StructLoggingConfig(wrapper_class=structlog.make_filtering_bound_logger(logging.INFO), ...)

This gives structlog the information it needs to be able to filter the logs it emits. A positive for this approach is that it can be quite a bit more efficient. Some downsides are that the logs are going through a different processor chain than the standard library ones (our default chains are different for either case), and logs aren't using the queue listener/handler configuration (is that an issue?).