exception

How to return a custom 404 Not Found page using FastAPI?

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Update A more elegant solution would be to use a custom exception handler, passing the status code of the exception you would like to handle, as shown below: from fastapi.responses import RedirectResponse from fastapi.exceptions import HTTPException @app.exception_handler(404) async def not_found_exception_handler(request: Request, exc: HTTPException): return RedirectResponse(‘https://fastapi.tiangolo.com’) or, use the exception_handlers parameter of the FastAPI class like … Read more

How do I create a directory, and any missing parent directories?

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On Python ≥ 3.5, use pathlib.Path.mkdir: from pathlib import Path Path(“/my/directory”).mkdir(parents=True, exist_ok=True) For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my take on it: Try os.path.exists, and consider os.makedirs for the creation. import os if not os.path.exists(directory): os.makedirs(directory) As noted in comments … Read more

How can I get WinForms to stop silently ignoring unhandled exceptions?

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In your Program.cs’ Main function you should also ensure that you’ve wrapped your call to open the form in a try/catch. Additionally use the AppDomain.UnhandledException to catch exceptions. We also add Application.ThreadException too. I believe the following will give you hooks into all the exceptions that can be thrown… static void Main() { try { … Read more

What happens if a constructor throws an exception?

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No, throwing an exception is the best way to signal an error during object construction. (Since there’s no return value, there’s no other way, other than constructing a headless object, which is bad style in C++.) From the man himself, Bjarne Stroustrup: http://www.stroustrup.com/bs_faq2.html#ctor-exceptions (If you are working in a project where exceptions aren’t allowed, then … Read more

Reflection MethodInfo.Invoke() catch exceptions from inside the method

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EDIT: As I understand your issue, the problem is purely an IDE one; you don’t like VS treating the exception thrown by the invocation of the MethodInfo as uncaught, when it clearly isn’t. You can read about how to resolve this problem here: Why is TargetInvocationException treated as uncaught by the IDE? It appears to … Read more

Close resource quietly using try-with-resources

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I found this answered on the coin-dev mailing list: http://mail.openjdk.java.net/pipermail/coin-dev/2009-April/001503.html 5. Some failures of the close method can be safely ignored (e.g., closing a file that was open for read). Does the construct provide for this? No. While this functionality seems attractive, it is not clear that it’s worth the added complexity. As a practical … Read more

How can I determine which exceptions can be thrown by a given method?

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Following up to my previous answer, I’ve managed to create a basic exception finder. It utilises a reflection-based ILReader class, available here on Haibo Luo’s MSDN blog. (Just add a reference to the project.) Updates: Now handles local variables and the stack. Correctly detects exceptions returned from method calls or fields and later thrown. Now … Read more