Setting `log_level="debug"` doesn't output debug log messages on console

Checklist

• The bug is reproducible against the latest release and/or master.
• There are no similar issues or pull requests to fix it yet.

Describe the bug

Using the latest uvicorn version 0.13.3 and fastapi version 0.63.0.

Bare minimum application to use logging:

import logging
from fastapi import FastAPI

app = FastAPI()
logger = logging.getLogger("foo")

@app.get("/")
def read_root():
    logger.debug("hello")
    return {"Hello": "World"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, port=8080, log_level="debug")

Output of running this file with python 3.8, and executing curl localhost:8080 in a separate terminal:

Press ENTER or type command to continue
INFO:     Started server process [19618]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://127.0.0.1:8080 (Press CTRL+C to quit)
INFO:     127.0.0.1:48340 - "GET / HTTP/1.1" 200 OK
^CINFO:     Shutting down
INFO:     Waiting for application shutdown.
INFO:     Application shutdown complete.
INFO:     Finished server process [19618]

To reproduce

Run the code above.

Expected behavior

I expect to see debug log messages on the console.

Actual behavior

Debug log messages do not show up. logger.error() messages do, but they are unformatted.

@app.get("/")
def read_root():
    logger.error("hello")
    return {"Hello": "World"}

produces:

INFO:     Started server process [19731]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://127.0.0.1:8080 (Press CTRL+C to quit)
hello
INFO:     127.0.0.1:48342 - "GET / HTTP/1.1" 200 OK

Debugging material

Environment

Python 3.8.2, Ubuntu 16.04, uvicorn version 0.13.3 and fastapi version 0.63.0.

Additional context

None

[uSpike]

That behavior seems wrong to me. I’d expect that at least passing debug=True / --debug would enable more verbose logging for all loggers. Requiring a user to provide a log configuration file when they’re trying to get a simple application running is a big ask.

[daidai21]

config log of logging level.

Setting the logging level of uvicorn.run() is different from that of logging module.

import logging
from fastapi import FastAPI

app = FastAPI()
logging.basicConfig(level=logging.DEBUG)   # add this line
logger = logging.getLogger("foo")

@app.get("/")
def read_root():
    logger.debug("hello")
    return {"Hello": "World"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, port=8080, log_level="debug")

This is execuate result:

➜  fastapi uvicorn log_lvl_conf:app
INFO:     Started server process [82468]
INFO:uvicorn.error:Started server process [82468]
INFO:     Waiting for application startup.
INFO:uvicorn.error:Waiting for application startup.
INFO:     Application startup complete.
INFO:uvicorn.error:Application startup complete.
INFO:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
INFO:uvicorn.error:Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
DEBUG:foo:hello
INFO:     127.0.0.1:64384 - "GET / HTTP/1.1" 200 OK