topic Re: client-state SDK: informations about error being thrown in Developer Q&A Forum

client-state SDK: informations about error being thrown

david_petroni — Thu, 20 Jul 2023 13:08:29 GMT

When using the client-state SDK, what is the best way to see when a key is not set vs when there are other issues? Would the snippet below be the right answer?

Thanks!

return stateClient .getAppState(...) .then(...) .catch((err) => { if (isErrorResponseError(err) && err.response.status === 404) { // key not set } else { throw err; } });

Re: client-state SDK: informations about error being thrown

gregor_riegler — Mon, 20 Nov 2023 10:36:35 GMT

I'm not sure what the isErrorResponseError function looks like, but basically it looks correct and something as below would work

return stateClient .getAppState(...) .then(...) .catch((err) => { const status = e?.response?.status; if (status && status === 404) { // key not set } else { throw err; } });

Alternatively, if the non-existence of a certain queried app state is a genuine scenario that you want to cover in your app you could also handle this without explicit error handling logic (as explained in https://developer.dynatrace.com/develop/data/state/#filter-states ) via

const oneElementOrEmpty: Array<{ key: string, value: string }> = await stateClient.getAppStates({ filter: "key = 'might-not-exist'", add-fields: "value", });

and build your logic based on empty/non-empty-array result.

Re: client-state SDK: informations about error being thrown

david_petroni — Fri, 21 Jul 2023 08:46:39 GMT

Indeed, this seems to be the way to go in my case, as it would not require specific error handling. Thanks!

Edit: FYI, `isErrorResponseError` is exposed in the SDK itself, and it seemed like the way to go, but next time I will use the "simplified" condition or the solution you provided without the explicit error handling 🙂