[release/9.4] Fix CLI hanging when dashboard fails to start by implementing ResourceFailedException (#10614)

* Initial plan

* Implement ResourceFailedException and update hosting/CLI to handle dashboard failures

Co-authored-by: mitchdenny <[email protected]>

* Add comprehensive tests for ResourceFailedException handling

Co-authored-by: mitchdenny <[email protected]>

* Address feedback: Move exception translation to AppHostRpcTarget and rename to DashboardStartupException

Co-authored-by: mitchdenny <[email protected]>

* Tweak wait logic.

* WIP: Working around exception JSON-RPC tear down issue.

* Fix test cases.

* Remove health check for dashboard.

* Copilot feedback.

* Remove whitespace change.

* PR feedback.

* Set default dashboard healthy state.

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: mitchdenny <[email protected]>
Co-authored-by: Mitch Denny <[email protected]>

Author: 3 people

src/Aspire.Cli/Backchannel/AppHostBackchannel.cs

@@ -14,7 +14,7 @@ namespace Aspire.Cli.Backchannel;
 internal interface IAppHostBackchannel
 {
     Task RequestStopAsync(CancellationToken cancellationToken);
-    Task<(string BaseUrlWithLoginToken, string? CodespacesUrlWithLoginToken)> GetDashboardUrlsAsync(CancellationToken cancellationToken);
+    Task<DashboardUrlsState> GetDashboardUrlsAsync(CancellationToken cancellationToken);
     IAsyncEnumerable<BackchannelLogEntry> GetAppHostLogEntriesAsync(CancellationToken cancellationToken);
     IAsyncEnumerable<RpcResourceState> GetResourceStatesAsync(CancellationToken cancellationToken);
     Task ConnectAsync(string socketPath, CancellationToken cancellationToken);
@@ -46,19 +46,18 @@ await rpc.InvokeWithCancellationAsync(
             cancellationToken);
     }
 
-    public async Task<(string BaseUrlWithLoginToken, string? CodespacesUrlWithLoginToken)> GetDashboardUrlsAsync(CancellationToken cancellationToken)
+    public async Task<DashboardUrlsState> GetDashboardUrlsAsync(CancellationToken cancellationToken)
     {
         using var activity = telemetry.ActivitySource.StartActivity();
         var rpc = await _rpcTaskCompletionSource.Task.WaitAsync(cancellationToken).ConfigureAwait(false);
 
         logger.LogDebug("Requesting dashboard URL");
 
-        var url = await rpc.InvokeWithCancellationAsync<DashboardUrlsState>(
+        var state = await rpc.InvokeWithCancellationAsync<DashboardUrlsState>(
             "GetDashboardUrlsAsync",
             [],
             cancellationToken);
-
-        return (url.BaseUrlWithLoginToken, url.CodespacesUrlWithLoginToken);
+        return state;
     }
 
     public async IAsyncEnumerable<BackchannelLogEntry> GetAppHostLogEntriesAsync([EnumeratorCancellation] CancellationToken cancellationToken)

src/Aspire.Cli/Commands/RunCommand.cs

@@ -172,6 +172,13 @@ protected override async Task<int> ExecuteAsync(ParseResult parseResult, Cancell
                 return await backchannel.GetDashboardUrlsAsync(cancellationToken);
             });
 
+            if (dashboardUrls.DashboardHealthy is false)
+            {
+                _interactionService.DisplayError(RunCommandStrings.DashboardFailedToStart);
+                _interactionService.DisplayLines(runOutputCollector.GetLines());
+                return ExitCodeConstants.DashboardFailure;
+            }
+
             _ansiConsole.WriteLine();
 
             var topGrid = new Grid();

src/Aspire.Cli/ExitCodeConstants.cs

@@ -17,4 +17,5 @@ internal static class ExitCodeConstants
     public const int AppHostIncompatible = 9;
     public const int ConfigNotFound = 10;
     public const int SdkNotInstalled = 11;
+    public const int DashboardFailure = 12;
 }

src/Aspire.Cli/Resources/RunCommandStrings.Designer.cs

@@ -155,4 +155,7 @@
   <data name="Logs" xml:space="preserve">
     <value>Logs</value>
   </data>
+  <data name="DashboardFailedToStart" xml:space="preserve">
+    <value>Aspire Dashboard failed to start.</value>
+  </data>
 </root>