Make resource HealthStatus computed from HealthReports

playground/HealthChecks/HealthChecksSandbox.AppHost/Program.cs

@@ -2,15 +2,16 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using Aspire.Hosting.Lifecycle;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Diagnostics.HealthChecks;
 
 var builder = DistributedApplication.CreateBuilder(args);
 
 builder.Services.TryAddLifecycleHook<TestResourceLifecycleHook>();
 
 AddTestResource("healthy", HealthStatus.Healthy, "I'm fine, thanks for asking.");
-AddTestResource("unhealthy", HealthStatus.Unhealthy, "I can't do that, Dave.", exception: GetException("Feeling unhealthy."));
-AddTestResource("degraded", HealthStatus.Degraded, "Had better days.", exception: GetException("Feeling degraded."));
+AddTestResource("unhealthy", HealthStatus.Unhealthy, "I can't do that, Dave.", exceptionMessage: "Feeling unhealthy.");
+AddTestResource("degraded", HealthStatus.Degraded, "Had better days.", exceptionMessage: "Feeling degraded.");
 
 #if !SKIP_DASHBOARD_REFERENCE
 // This project is only added in playground projects to support development/debugging
@@ -24,28 +25,22 @@
 
 builder.Build().Run();
 
-static string GetException(string message)
+IResourceBuilder<TestResource> AddTestResource(string name, HealthStatus status, string? description = null, string? exceptionMessage = null)
 {
-    try
-    {
-        throw new InvalidOperationException(message);
-    }
-    catch (InvalidOperationException ex)
-    {
-        return ex.ToString();
-    }
-}
+    builder.Services.AddHealthChecks()
+                    .AddCheck(
+                        $"{name}_check",
+                        () => new HealthCheckResult(status, description, new InvalidOperationException(exceptionMessage))
+                        );
 
-IResourceBuilder<TestResource> AddTestResource(string name, HealthStatus status, string? description = null, string? exception = null)
-{
     return builder
         .AddResource(new TestResource(name))
+        .WithHealthCheck($"{name}_check")
         .WithInitialState(new()
         {
             ResourceType = "Test Resource",
             State = "Starting",
             Properties = [],
-            HealthReports = [new HealthReportSnapshot($"{name}_check", status, description, exception)]
         })
         .ExcludeFromManifest();
 }

src/Aspire.Dashboard/Model/ResourceStateViewModel.cs

@@ -62,12 +62,6 @@ internal static ResourceStateViewModel GetStateViewModel(ResourceViewModel resou
             icon = new Icons.Filled.Size16.Circle();
             color = Color.Info;
         }
-        else if (resource.HealthStatus is null)
-        {
-            // If we are waiting for a health check, show a progress bar and consider the resource unhealthy
-            icon = new Icons.Filled.Size16.CheckmarkCircleWarning();
-            color = Color.Warning;
-        }
         else if (resource.HealthStatus is not HealthStatus.Healthy)
         {
             icon = new Icons.Filled.Size16.CheckmarkCircleWarning();

src/Aspire.Dashboard/Resources/Resources.resx

@@ -233,7 +233,7 @@
     <value>View console logs</value>
   </data>
   <data name="ResourcesDetailsHealthStateProperty" xml:space="preserve">
-    <value>Health State</value>
+    <value>Health state</value>
   </data>
   <data name="ResourcesDetailsStopTimeProperty" xml:space="preserve">
     <value>Stop time</value>
@@ -262,4 +262,4 @@
   <data name="ResourceActionTelemetryTooltip" xml:space="preserve">
     <value>No telemetry found for this resource.</value>
   </data>
-</root>
+</root>

src/Aspire.Hosting/ApplicationModel/CustomResourceSnapshot.cs

@@ -12,6 +12,9 @@ namespace Aspire.Hosting.ApplicationModel;
 /// </summary>
 public sealed record CustomResourceSnapshot
 {
+    private readonly ImmutableArray<HealthReportSnapshot> _healthReports = [];
+    private readonly ResourceStateSnapshot? _state;
+
     /// <summary>
     /// The type of the resource.
     /// </summary>
@@ -40,7 +43,15 @@ public sealed record CustomResourceSnapshot
     /// <summary>
     /// Represents the state of the resource.
     /// </summary>
-    public ResourceStateSnapshot? State { get; init; }
+    public ResourceStateSnapshot? State
+    {
+        get => _state;
+        init
+        {
+            _state = value;
+            HealthStatus = ComputeHealthStatus(_healthReports, value?.Text);
+        }
+    }
 
     /// <summary>
     /// The exit code of the resource.
@@ -52,11 +63,10 @@ public sealed record CustomResourceSnapshot
     /// </summary>
     /// <remarks>
     /// <para>
-    /// This value is derived from <see cref="HealthReports"/>. If a resource is known to have a health check
-    /// and no reports exist, or if a resource does not have a health check, then this value is <see langword="null"/>.
+    /// This value is derived from <see cref="HealthReports"/>.
     /// </para>
     /// </remarks>
-    public HealthStatus? HealthStatus { get; init; }
+    public HealthStatus? HealthStatus { get; private set; }
 
     /// <summary>
     /// The health reports for this resource.
@@ -65,7 +75,15 @@ public sealed record CustomResourceSnapshot
     /// May be zero or more. If there are no health reports, the resource is considered healthy
     /// so long as no heath checks are registered for the resource.
     /// </remarks>
-    public ImmutableArray<HealthReportSnapshot> HealthReports { get; init; } = [];
+    public ImmutableArray<HealthReportSnapshot> HealthReports
+    {
+        get => _healthReports;
+        internal init
+        {
+            _healthReports = value;
+            HealthStatus = ComputeHealthStatus(value, State?.Text);
+        }
+    }
 
     /// <summary>
     /// The environment variables that should show up in the dashboard for this resource.
@@ -86,6 +104,22 @@ public sealed record CustomResourceSnapshot
     /// The commands available in the dashboard for this resource.
     /// </summary>
     public ImmutableArray<ResourceCommandSnapshot> Commands { get; init; } = [];
+
+    internal static HealthStatus? ComputeHealthStatus(ImmutableArray<HealthReportSnapshot> healthReports, string? state)
+    {
+        if (state != KnownResourceStates.Running)
+        {
+            return null;
+        }
+
+        return healthReports.Length == 0
+            // If there are no health reports and the resource is running, assume it's healthy.
+            ? Microsoft.Extensions.Diagnostics.HealthChecks.HealthStatus.Healthy
+            // If there are health reports, the health status is the minimum of the health status of the reports.
+            // If any of the reports is null (first health check has not returned), the health status is unhealthy.
+            : healthReports.MinBy(r => r.Status)?.Status
+                ?? Microsoft.Extensions.Diagnostics.HealthChecks.HealthStatus.Unhealthy;
+    }
 }
 
 /// <summary>

src/Aspire.Hosting/ApplicationModel/ResourceNotificationService.cs

@@ -352,7 +352,6 @@ public Task PublishUpdateAsync(IResource resource, string resourceId, Func<Custo
             var newState = stateFactory(previousState);
 
             newState = UpdateCommands(resource, newState);
-            newState = UpdateHealthStatus(resource, newState);
 
             notificationState.LastSnapshot = newState;
 
@@ -377,11 +376,10 @@ public Task PublishUpdateAsync(IResource resource, string resourceId, Func<Custo
             {
                 _logger.LogTrace("Resource {Resource}/{ResourceId} update published: " +
                     "ResourceType = {ResourceType}, CreationTimeStamp = {CreationTimeStamp:s}, State = {{ Text = {StateText}, Style = {StateStyle} }}, " +
-                    "HealthStatus = {HealthStatus} " +
                     "ExitCode = {ExitCode}, EnvironmentVariables = {{ {EnvironmentVariables} }}, Urls = {{ {Urls} }}, " +
                     "Properties = {{ {Properties} }}",
                     resource.Name, resourceId,
-                    newState.ResourceType, newState.CreationTimeStamp, newState.State?.Text, newState.State?.Style, newState.HealthStatus,
+                    newState.ResourceType, newState.CreationTimeStamp, newState.State?.Text, newState.State?.Style,
                     newState.ExitCode, string.Join(", ", newState.EnvironmentVariables.Select(e => $"{e.Name} = {e.Value}")), string.Join(", ", newState.Urls.Select(u => $"{u.Name} = {u.Url}")),
                     string.Join(", ", newState.Properties.Select(p => $"{p.Name} = {p.Value}")));
             }
@@ -390,20 +388,6 @@ public Task PublishUpdateAsync(IResource resource, string resourceId, Func<Custo
         return Task.CompletedTask;
     }
 
-    /// <summary>
-    /// Update resource snapshot health status if the resource is running with no health checks.
-    /// </summary>
-    private static CustomResourceSnapshot UpdateHealthStatus(IResource resource, CustomResourceSnapshot previousState)
-    {
-        // A resource is also healthy if it has no health check annotations and is in the running state.
-        if (previousState.HealthStatus is not HealthStatus.Healthy && !resource.TryGetAnnotationsIncludingAncestorsOfType<HealthCheckAnnotation>(out _) && previousState.State?.Text == KnownResourceStates.Running)
-        {
-            return previousState with { HealthStatus = HealthStatus.Healthy };
-        }
-
-        return previousState;
-    }
-
     /// <summary>
     /// Use command annotations to update resource snapshot.
     /// </summary>

src/Aspire.Hosting/Dashboard/DashboardServiceData.cs

@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-using System.Collections.Immutable;
 using System.Runtime.CompilerServices;
 using Aspire.Hosting.ApplicationModel;
 using Microsoft.Extensions.Logging;
@@ -50,31 +49,9 @@ static GenericResourceSnapshot CreateResourceSnapshot(IResource resource, string
                     State = snapshot.State?.Text,
                     StateStyle = snapshot.State?.Style,
                     HealthStatus = snapshot.HealthStatus,
-                    HealthReports = GetOrCreateHealthReports(),
+                    HealthReports = snapshot.HealthReports,
                     Commands = snapshot.Commands
                 };
-
-                ImmutableArray<HealthReportSnapshot> GetOrCreateHealthReports()
-                {
-                    if (!resource.TryGetAnnotationsIncludingAncestorsOfType<HealthCheckAnnotation>(out var annotations))
-                    {
-                        return snapshot.HealthReports;
-                    }
-
-                    var enumeratedAnnotations = annotations.ToList();
-                    if (snapshot.HealthReports.Length == enumeratedAnnotations.Count)
-                    {
-                        return snapshot.HealthReports;
-                    }
-
-                    var reportsByKey = snapshot.HealthReports.ToDictionary(report => report.Name);
-                    foreach (var healthCheckAnnotation in enumeratedAnnotations.Where(annotation => !reportsByKey.ContainsKey(annotation.Key)))
-                    {
-                        reportsByKey.Add(healthCheckAnnotation.Key, new HealthReportSnapshot(healthCheckAnnotation.Key, null, null, null));
-                    }
-
-                    return [..reportsByKey.Values];
-                }
             }
 
             var timestamp = DateTime.UtcNow;