How to use/reference properties that's needed by the resource that's being created? ('Microsoft.Graph/applications@v1.0')

[OranguTech]

(This might be a more basic/general Bicep question)

Trying to create an app registration (https://learn.microsoft.com/en-us/graph/templates/bicep/reference/applications?view=graph-bicep-1.0), need to fill in the identifierUris: property, which in this case would be "api://{appId}", but of course we can't get/know the appID until the registration is created...

Is there some way to reference that? Something like "this" or "self"? (Something like identifierUris: = array ['api://${self.appId}'] )

[eketo-msft]

I think you need to do something like:

 extension microsoftGraphV1
 
 @description('Client-provided unique name for the app (alternate key, immutable).')
 param appUniqueName string
 
 @description('Display name for the app.')
 param appDisplayName string
 
 // Step 1: Create the app. appId is server-generated.
 resource app 'Microsoft.Graph/applications@v1.0' = {
   uniqueName: appUniqueName
   displayName: appDisplayName
   signInAudience: 'AzureADMyOrg'
 }
 
 // Step 2:  Update against the same app (matched by uniqueName) to set
 // identifierUris using the appId from step 1.
 resource appIdentifierUris 'Microsoft.Graph/applications@v1.0' = {
   uniqueName: appUniqueName
   identifierUris: [
     'api://${app.appId}'
   ]
 }
 
 output identifierUri string = appIdentifierUris.identifierUris[0]