TypeError in Uvicorn logging module

[SkandaPrasad-S]

---

Description:
When running the Uvicorn server with the provided configuration in main.py, a TypeError is encountered within the logging module. This issue occurs during the formatting of log messages, specifically when trying to format numerical placeholders such as %d.

Steps to Reproduce:

1. Run the command python main.py in the project directory.
2. Observe the traceback output in the console.

Expected Behavior:
The Uvicorn server should start without any errors or exceptions.

Actual Behavior:
A TypeError is raised during the logging process, leading to a failure to start the server.

Error Message:

TypeError: %d format: a real number is required, not str

Additional Information:

• This issue seems to be related to the handling of numerical placeholders in log messages.
• The problem appears to originate from the logging module used by Uvicorn.
• The error occurs in the E:\Software\Lib\logging\__init__.py file, specifically in the emit method.

---

Here is the full error

--- Logging error ---
Traceback (most recent call last):
  File "E:\Software\Lib\logging\__init__.py", line 1110, in emit
    msg = self.format(record)
          ^^^^^^^^^^^^^^^^^^^
  File "E:\Software\Lib\logging\__init__.py", line 953, in format
    return fmt.format(record)
           ^^^^^^^^^^^^^^^^^^
  File "E:\Software\Lib\logging\__init__.py", line 687, in format
    record.message = record.getMessage()
                     ^^^^^^^^^^^^^^^^^^^
  File "E:\Software\Lib\logging\__init__.py", line 377, in getMessage
    msg = msg % self.args
          ~~~~^~~~~~~~~~~
TypeError: %d format: a real number is required, not str
Call stack:
  File "E:\Perfection\supabaseWithFastAPI\main.py", line 19, in <module>
    uvicorn.run(app=app, host="localhost", port="8080")
  File "E:\Perfection\supabaseWithFastAPI\venv\Lib\site-packages\uvicorn\main.py", line 587, in run
    server.run()
  File "E:\Perfection\supabaseWithFastAPI\venv\Lib\site-packages\uvicorn\server.py", line 62, in run
    return asyncio.run(self.serve(sockets=sockets))
  File "E:\Software\Lib\asyncio\runners.py", line 190, in run
    return runner.run(main)
  File "E:\Software\Lib\asyncio\runners.py", line 118, in run
    return self._loop.run_until_complete(task)
  File "E:\Software\Lib\asyncio\base_events.py", line 640, in run_until_complete
    self.run_forever()
  File "E:\Software\Lib\asyncio\windows_events.py", line 321, in run_forever
    super().run_forever()
  File "E:\Software\Lib\asyncio\base_events.py", line 607, in run_forever
    self._run_once()
  File "E:\Software\Lib\asyncio\base_events.py", line 1919, in _run_once
    handle._run()
  File "E:\Software\Lib\asyncio\events.py", line 80, in _run
    self._context.run(self._callback, *self._args)
  File "E:\Perfection\supabaseWithFastAPI\venv\Lib\site-packages\uvicorn\server.py", line 79, in serve
    await self.startup(sockets=sockets)
  File "E:\Perfection\supabaseWithFastAPI\venv\Lib\site-packages\uvicorn\server.py", line 178, in startup
    self._log_started_message(listeners)
  File "E:\Perfection\supabaseWithFastAPI\venv\Lib\site-packages\uvicorn\server.py", line 219, in _log_started_message
    logger.info(
Message: 'Uvicorn running on %s://%s:%d (Press CTRL+C to quit)'
Arguments: ('http', 'localhost', '8080')

[gincla]

Experiencing the same.
Is this actually a FastAPI error or are we just doing something wrong?

[theyashl]

The port parameter is of type int (port: int), you're providing port as string, it should be a number without quotes.
IDK if uvicorn should explicitly cast the port to int or not but your issue lies with that parameter only.