What is the correct way of retrieving async values in a cust

Question

What is the correct way of retrieving async values in a custom `ComponentResource` We struggle with having a stack hanging if the async requests fails We are doing something like this ```export class Team extends pulumi ComponentResource teamId pulumi Output lt string gt constructor name string teamSpec types TeamSpec super something name const azureAdConfig = azuread getClientConfig const usersIds = pulumi output getUsers teamSpec members getUsers is something that returns a promise const adGroup = new azuread Group `$ teamSpec teamName ad group` displayName teamSpec teamName owners azureAdConfig then c = gt c objectId description Created and managed by Automation securityEnabled true members usersIds ``` if the call to `getUsers` fails everything will just hang I would expect pulumi to catch that and fail the whole process Am I doing something wrong or is this a bug

little-cartoon-10569 · Answer

Generally async stuff is either 1 done in the provider not the resource or 2 is not resolved then apply in the constructor but left as a property with an Output value

little-cartoon-10569 · Answer

Can you expose userIds as a property rather than a local variable

little-cartoon-10569 · Answer

The dependency on it in adGroup is fine since Pulumi will handle that Are there any other dependencies on it further down

wet-noon-14291 · Answer

We need it when creating the adGroup which we do want to do in the constructor I think since we do want a concept of a team that has a set of children

wet-noon-14291 · Answer

nope that is the only dependency

wet-noon-14291 · Answer

so you re saying I can just depend directly on the promise and not resolve it

little-cartoon-10569 · Answer

Since that s the only use of it I don t think it should be causing a problem Does the code inside `getUsers ` resolve anything outside of the Promise If everything is deferred until the Pulumi engine is doing its thing you should be okay

wet-noon-14291 · Answer

It is quite simple ```const getUsers = async members string = gt const users = await azuread getUsers userPrincipalNames members return users objectIds ```

little-cartoon-10569 · Answer

Heh that was exactly the example I was coming up with slightly smiling face

little-cartoon-10569 · Answer

That won t work since you re awaiting before the engine gets involved

little-cartoon-10569 · Answer

Try doing the work inside a `then ` instead of an async await block

little-cartoon-10569 · Answer

Same thing effectively but I think Pulumi handles it better because it s close to Output apply

wet-noon-14291 · Answer

got it so it is the async await stuff that is causing the problem Promise style will work last famous words

little-cartoon-10569 · Answer

That s my understanding yes

little-cartoon-10569 · Answer

Plus you can skip the extra function slightly smiling face

wet-noon-14291 · Answer

yes

little-cartoon-10569 · Answer

`pulumi output azuread getUsers userPrincipalNames members then u = gt u objectIds `

little-cartoon-10569 · Answer

Or equivalently `pulumi output azuread getUsers userPrincipalNames members apply u = gt u objectIds `

little-cartoon-10569 · Answer

I would go with the 2nd one since then the Pulumi dependency resolution logic gets involved earlier and maybe can make better decisions

wet-noon-14291 · Answer

ok so I still need to put it in an output

wet-noon-14291 · Answer

hm still same issue I know I can work my way around it by validating the input it is an automation application but I do want to understand why it isn t working and failing as expected

wet-noon-14291 · Answer

so the correct way to do it is to move all the async calls out from the constructor I think Then I got it behaving like I expected

wet-noon-14291 · Answer

One question I have though is how should one go about getting values async if they depend on the output from another resource Does that also have to be done outside of a constructor or maybe pulumi knows how to deal with that properly since it is a resource creating the output

little-cartoon-10569 · Answer

I was under the impression that if the value is to be passed into a resource constructor it would be fine to retrieve the value inside an apply and pass the returned output to the constructor But that didn t work for you yesterday so I m at a loss to explain this

wet-noon-14291 · Answer

Maybe < broad dog 22463> can help explain Or can point to someone It isn t urgent by any means but it would be nice to understand what the right way is