[WebToolsE2E][Aspire]After adding Azure Key Vault to AppHost project, F5 failed with exception: One or more errors occurred. (No output for vaultUri)

[v-cazhang]

REGRESSION INFO: Works fine on Aspire 8.0.0-preview.3.24105.21

INSTALL STEPS

1. Clean machine: Win11 x64 23h2 ENU
2. Install 17.10.0 Preview 2.0 [34701.141.d17.10] (Includes Aspire 8.0.0-preview.4.24129.7)
3. Apply NuGet Feeds
4. Install Docker Desktop

REPRO STEPS

1. New Project > ASP.NET Core Empty project > name it AspireKeyVault02 > .NET 8.0 > check 'Enlist in Aspire Orchestration' > create
2. Open appsettings.json of AppHost project, add connection string:

"ConnectionStrings": {
  "secretConnectionName": "https://<vault_account_name>.vault.azure.net/"
}

3. In your AppHost project, install the Aspire Azure Hosting package and save the file
4. Open Program.cs of AspireKeyVault02.AppHost project, add following codes:

	var keyVault = builder.AddAzureKeyVault("[secretConnectionName]");
        var myService = builder.AddProject<Projects.AspireKeyVault02>("aspirekeyvault02")
                       .WithReference(keyVault);

6. Build and F5

ACTUAL
It shows an exception during F5

System.AggregateException
HResult=0x80131500
Message=One or more errors occurred. (No output for vaultUri)
Source=System.Private.CoreLib
StackTrace:
at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at System.Threading.Tasks.Task.Wait()
at Aspire.Hosting.DistributedApplication.Run()
at Program.

$(String[] args) in C:\Users\v-cazhang\source\repos\WebApplication2\WebApplication2.AppHost\Program.cs:line 11

This exception was originally thrown at this call stack:
[External Code]

Inner Exception 1:
InvalidOperationException: No output for vaultUri

EXPECTED
F5 successfully.

[davidfowl]

This pattern no longer works for azure resources. Dupe of #2395

[balachir]

@davidfowl the README file for Aspire.Azure.Security.KeyVault component recommends this builder.AddAzureKeyVault pattern in the AppHost section of the README. Will the README also get updated as part of the fix for #2395 or should we open a separate issue to fix the README for P5?

[davidfowl]

That's a good point. It applies to the application and to the app host as well, but not the AddKeyVault method. @eerhardt What do you think? Do we update the readmes to add this "use existing keyvault vs new keyvault" scenario?

[eerhardt]

If the READMEs no longer point to valid information/scenarios we need to update them. What is the recommended pattern here for someone who isn't using AzureProvisioning? (or do we start recommend using AzureProvisioning in the READMEs?)

[davidfowl]

This: #2395 (comment)

[eerhardt]

This has been completed with #3793.