Set ensure_ascii=False on json.dumps() for WebSocket.send_json()

[xiayouran]

Summary

When the data output by the send_json function is in Chinese, it will force Chinese characters to be converted to Unicode, so I fixed this issue.(The most fundamental reason is that the value of the ensure_ascii parameter was not modified when using the json.dumps function)

Checklist

• [√] I understand that this PR may be closed in case there was no previous discussion. (This doesn't apply to typos!)
• [√] I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• [√] I've updated the documentation accordingly.

[Kludex]

I think we have some issues about this around. Can we link them here?

[abersheeran]

I'm not sure what problem you encountered that requires adding this option. Sending Chinese should still work fine without using this option. Can you provide a more detailed description of what kind of problem this solves? (Converting Chinese to Unicode encoding is not a problem, it is standard-compliant.)

[xiayouran]

Yes, from the perspective of the code workflow, there is no problem. I am building a Chinese question and answer system, but when using send_json function sends Chinese characters, my front-end display is Unicode characters instead of Chinese characters, so I want to solve this problem. The problem lies in the fact that the json.dumps function did not set the ensure_ascii parameter to False.

[abersheeran]

I verified it, and it was

[Kludex]

Can we add a test case?

[Kludex]

Yeah, according to the spec (https://asgi.readthedocs.io/en/latest/specs/www.html#send-send-event), there was no need to ensure_ascii here. 👍