Sanic: Exception occured while handling uri: unknown

[xMistt]

Describe the bug
Randomly I get the exception:

[2020-08-24 04:50:26 +0100] [2348] [ERROR] Exception occurred while handling uri: unknown
NoneType: None

Code snippet
No code as I don't know causes this error.

Expected behavior
No exception.

Environment (please complete the following information):

• OS: Windows 10
• Version: 19.12.2

Additional context
I've got a websocket server running in the same script but when receiving/connecting/sending messages, the exception isnt raised then, it's raised randomly.

[ahopkins]

What kind of exception handlers do you have? Is this a full blown app or an MVP? Possibly something in your Middleware is messing up the request object. Have you tried to narrow it down at all?

[xMistt]

I've got no middleware & yes it is a MVP.

[xMistt]

And exception handler? Is this some sort of event?

[ahopkins]

can you provide any kind of code snippet?

[xMistt]

No code in particular causes this so I'm not sure what snippet of code to send, want the full code?

[ahopkins]

If you don't mind. It is near impossible to figure it out without knowing what you are running. 😬

If you would prefer to send privately, send me a private message on the forums

https://community.sanicframework.org

[xMistt]

Here is my source code from the script that I get the error from: https://hastebin.com/nuhuwobugu.py

[sjsadowski]

I stripped out everything unrelated to sanic, and it works fine: https://gist.github.com/sjsadowski/a2c5dc52967d3a68c0083370c1477334

I think your problem is with something not-sanic.

Also: windows support for sanic is best-effort, so there could be something else going on there.

[xMistt]

Is there any way to just ignore these exceptions?

[ahopkins]

You are running two servers from the same loop? This is definitely a less than ideal setup. Two things:

1. Sanic has websocket handlers. There is no need to run a seperate service.
2. If you _need_ to keep it seperate (different domain/port/etc), then it should be done in a separate process.

I have not run the code to look at it, but I suspect this is a problem.

---

Last thing, running Sanic this way is less than ideal. I would not suggest using run_until_complete and run_forever unless you absolutely have to. For _most_ situations where you need to run something along side Sanic (and need access to the loop), it should be done in a listener.

Application developers should typically use the high-level asyncio functions, such as asyncio.run(), and should rarely need to reference the loop object or call its methods. This section is intended mostly for authors of lower-level code, libraries, and frameworks, who need finer control over the event loop behavior

Source

[sjsadowski]

@ahopkins I will try and add a best practices document for communication between two servers using a queue. It seems like we're answering this question/pattern of thinking very often because of the assumption that in order to communicate, these things need to be running in the same loop in the same application.

[ahopkins]

I will try and add a best practices document for communication between two servers using a queue

I can do you one better. I am working on a user guide (will send you the repo) to hold lots of examples and a more tutorial style walk through of Sanic.

[sjsadowski]

I'll put it there, seems like a great place for it.

[stale[bot]]

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