fix: issue with logging

[ekalosak]

Summary

I removed an invalid argument to a logging.warning call.

Related

#130

What was broken

As-is, the logging block for missing content-type headers is:

def _on_call_valid_content_type(request: _Request) -> bool:
    """Validate content"""
    content_type: str | None = request.headers.get("Content-Type")

    if content_type is None:
        _logging.warning("Request is missing Content-Type.", content_type)
        return False
...

In the conditional block, you can see the None positional arg content_type passed to the logging call. Python logging doesn't allow null positional (nor keyword) args. The logging used in this module is indeed stdlib Python logging cf functions-framework-python from which it is imported.

A minimal reproducible example

Using Python 3.11.4, python -c 'import logging; logging.warning("this will raise an exception", None)'

Expected result

--- Logging error ---
Traceback (most recent call last):
  File "/.../3.11.4/lib/python3.11/logging/__init__.py", line 1110, in emit
    msg = self.format(record)
          ^^^^^^^^^^^^^^^^^^^
  File "/.../3.11.4/lib/python3.11/logging/__init__.py", line 953, in format
    return fmt.format(record)
           ^^^^^^^^^^^^^^^^^^
  File "/...versions/3.11.4/lib/python3.11/logging/__init__.py", line 687, in format
    record.message = record.getMessage()
                     ^^^^^^^^^^^^^^^^^^^
  File "/.../python3.11/logging/__init__.py", line 377, in getMessage
    msg = msg % self.args
          ~~~~^~~~~~~~~~~
TypeError: not all arguments converted during string formatting
Call stack:
  File "<string>", line 1, in <module>
Message: 'this will raise an exception'
Arguments: (None,)

[exaby73]

LGTM