Hello! I’m starting a personal project in .NET.

For a logging solution, I want to achieve something similar to what I have in a Python REST API I wrote a while back using the decorator pattern (example in the image).

In the example, the outter “log” function receives the logger I want to use, the decorator function receives a function and returns the decorated function ready to be called (this would be the decorator), and the wrapper function receives the same arguments as the function to be decorated (which is a generic (*args, **kwargs) ofc, because it’s meant to decorate any function) and returns whatever the return type of the function is (so, Any). In lines 17 - 24 I just call the passed in “func” with the passed in arguments, but in between I wrap it in a try except block and log that the function with name func.__name__ started or finished executing. In practice, using this decorator in Python looks like this:

import logging
from my.decorator.module import log

_logger = logging.getLogger(__name__)

@log(_logger)
def my_func(arg1: Arg1Type, arg2: Arg2Type) -> ReturnType:
    ...

Ofc it’s a lot simpler in Python, however I was wondering if it would be possible or even recommended to attempt something similar in C#. I wouldn’t mind having to call the function and wrap it manually, something like this:

return RunWithLogs(MyFunction, arg1, arg2);

What I do want to avoid is manually writing the log statements inside the service’s business logic, or having to write separate wrappers for each method I want to log. Would be nice to have one generic function or class that I can somehow plug-in to any method and have it log when the call starts and finishes.

Any suggestions? Thanks in advance.

  • @Lmaydev
    link
    24 months ago

    Won’t you need to handle all the different expressions the parameter could be with this method? It won’t always be a constant right?

    • @[email protected]
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      fedilink
      24 months ago

      Yes, as I stated other expression types might be needed. You could also wrap the argument expression in Expression.Lambda() and execute it to get the value. None of these options are necessarily fast, and you’ll likely get double executions which could lead to unanticipated side effects.

      • @Lmaydev
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        14 months ago

        I think taking the parameters as parameters and creating a function for each parameter count is better then you can just call the func/action normally.