SignalR CORS add/remove not atomic

[Arithmomaniac]

https://github.com/Azure/azure-cli/blob/e015d5bcba0c2d21dc42189daa43dc1eb82d2485/src/azure-cli/azure/cli/command_modules/signalr/cors.py#L16-L35

While appreciating that the underlying API does not support atomic operations here, someone not knowing that and working on a system where CORS is programmatically enabled for new clients could potentially lose writes in a race condition. (I'm actually working on such a system now.

Suggestion: the non-atomicity should (a) be clearly documented in docs, and/or (b) the methods should be deprecated and replaced with a signalr cors set that operates on the whole list.

[ghost]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @sffamily, @chenkennt.

Issue Details

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https://github.com/Azure/azure-cli/blob/e015d5bcba0c2d21dc42189daa43dc1eb82d2485/src/azure-cli/azure/cli/command_modules/signalr/cors.py#L16-L35 While appreciating that the underlying API does not support atomic operations here, someone not knowing that and working on a system where CORS is programmatically enabled for new clients could potentially lose writes in a race condition. (I'm actually working on such a system now. Suggestion: the non-atomicity should (a) be clearly documented in docs, and/or (b) the methods should be deprecated and replaced with a `signalr cors set` that operates on the whole list.

Author:	Arithmomaniac
Assignees:	-
Labels:	`Service Attention`, `SignalR`, `question`
Milestone:	-

[yonzhan]

route to SignalR service team to help with.

[chenkennt]

@zackliu please help take a look.

[zackliu]

@Arithmomaniac We will add a set operation and update the document to make it clear. As cors add/remove operation are common in cli, I think we can keep it.

[holtalanm]

this is also not an idempotent command, which results in needing to check the list of CORs before adding.