Updating observes from server?

[sheosi]

Hi!!! I want to use CoAP-rs for voice assistant components, and we need to use observe, however, there's no support for updating the resources from the server anymore and trying to access the same server from a client in the same process (as a workaround) throws:

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 11, kind: WouldBlock, message: "Resource temporarily unavailable" }'

Is server-side resource update planned again, or at least, can the workaround be made to work in the meantime?

[wuyingfengsui]

Have you try the example? I think it can be work just change the client method get to put

[sheosi]

It might be because client and server are in different threads in the example? I might have to try that.

[sheosi]

Gave it a try, using that same example and changing CoAPClient::get(url) with CoAPClient::put(url, vec![]) gives the same error as before.

[wuyingfengsui]

let response = CoAPClient::put(url, vec![]).unwrap(); works on my computer. Which OS you are using?

[sheosi]

Linux, Fedora 35. You think that might be the cause?

[wuyingfengsui]

Maybe. The error occur on a non-blocking socket. The linux has its' own non-blocking system. Have you try to start the client a little later?

[sheosi]

That was it, adding a barrier (a oneshot channel too, pretty much anything to sync them up) was enough for the example to work. I still think the underlying problem is not resolved, but maybe this could be added as a workaround? It would be useful to have this in an example, as part of the documentation or even inside the library itself (if it makes sense).

[wuyingfengsui]

It relates to the OS type. Only a few of OS has the problem. I will add some comments in the example later.

[sheosi]

Also, add that the thread is mandatory, otherwise it produces an error as well.

[Covertness]

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