Extension methods on IDistributedApplicationBuilder for subscribing to application level events.

playground/DotnetTool/DotnetTool.AppHost/AppHost.cs

@@ -85,7 +85,7 @@
 
 // Some issues only show up when installing for first time, rather than using existing downloaded versions
 // Use a specific NUGET_PACKAGES path for these playground tools, so we can easily reset them
-builder.Eventing.Subscribe<BeforeStartEvent>(async (evt, _) =>
+builder.OnBeforeStart(async (evt, _) =>
 {
     var nugetPackagesPath = Path.Join(evt.Services.GetRequiredService<IAspireStore>().BasePath, "nuget");
 

src/Aspire.Hosting.Azure.ContainerRegistry/AzureContainerRegistryExtensions.cs

@@ -76,7 +76,7 @@ public static IResourceBuilder<AzureContainerRegistryResource> AddAzureContainer
     /// </summary>
     private static void SubscribeToAddRegistryTargetAnnotations(IDistributedApplicationBuilder builder, AzureContainerRegistryResource registry)
     {
-        builder.Eventing.Subscribe<BeforeStartEvent>((beforeStartEvent, cancellationToken) =>
+        builder.OnBeforeStart((beforeStartEvent, cancellationToken) =>
         {
             foreach (var resource in beforeStartEvent.Model.Resources)
             {

src/Aspire.Hosting.Azure.CosmosDB/AzureCosmosDBExtensions.cs

@@ -408,7 +408,7 @@ public static IResourceBuilder<AzureCosmosDBResource> WithAccessKeyAuthenticatio
         // need to do this later in case builder becomes an emulator after this method is called.
         if (builder.ApplicationBuilder.ExecutionContext.IsRunMode)
         {
-            builder.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((data, _) =>
+            builder.ApplicationBuilder.OnBeforeStart((data, _) =>
             {
                 if (builder.Resource.IsEmulator)
                 {

src/Aspire.Hosting.Azure.Functions/AzureFunctionsProjectResourceExtensions.cs

@@ -148,7 +148,7 @@ private static IResourceBuilder<AzureFunctionsProjectResource> AddAzureFunctions
                 .Resource;
         }
 
-        builder.Eventing.Subscribe<BeforeStartEvent>((data, token) =>
+        builder.OnBeforeStart((data, token) =>
         {
             var removeStorage = true;
             // Look at all of the resources and if none of them use the default storage, then we can remove it.

src/Aspire.Hosting.Azure.PostgreSQL/AzurePostgresExtensions.cs

@@ -300,7 +300,7 @@ public static IResourceBuilder<AzurePostgresFlexibleServerResource> WithPassword
         // need to do this later in case builder becomes an emulator after this method is called.
         if (builder.ApplicationBuilder.ExecutionContext.IsRunMode)
         {
-            builder.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((data, token) =>
+            builder.ApplicationBuilder.OnBeforeStart((data, token) =>
             {
                 if (builder.Resource.IsContainer())
                 {

src/Aspire.Hosting.Azure.Redis/AzureManagedRedisExtensions.cs

@@ -133,7 +133,7 @@ public static IResourceBuilder<AzureManagedRedisResource> WithAccessKeyAuthentic
         // need to do this later in case builder becomes an emulator after this method is called.
         if (builder.ApplicationBuilder.ExecutionContext.IsRunMode)
         {
-            builder.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((data, token) =>
+            builder.ApplicationBuilder.OnBeforeStart((data, token) =>
             {
                 if (builder.Resource.IsContainer())
                 {

src/Aspire.Hosting.Azure.Redis/AzureRedisExtensions.cs

@@ -206,7 +206,7 @@ public static IResourceBuilder<AzureRedisCacheResource> WithAccessKeyAuthenticat
         // need to do this later in case builder becomes an emulator after this method is called.
         if (builder.ApplicationBuilder.ExecutionContext.IsRunMode)
         {
-            builder.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((data, token) =>
+            builder.ApplicationBuilder.OnBeforeStart((data, token) =>
             {
                 if (builder.Resource.IsContainer())
                 {

src/Aspire.Hosting.JavaScript/JavaScriptHostingExtensions.cs

@@ -260,7 +260,7 @@ public static IResourceBuilder<NodeAppResource> AddNodeApp(this IDistributedAppl
 
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((_, _) =>
+            builder.OnBeforeStart((_, _) =>
             {
                 // set the command to the package manager executable if the JavaScriptRunScriptAnnotation is present
                 if (resourceBuilder.Resource.TryGetLastAnnotation<JavaScriptRunScriptAnnotation>(out _) &&
@@ -463,7 +463,7 @@ private static IResourceBuilder<TResource> CreateDefaultJavaScriptAppBuilder<TRe
         // ensure the package manager command is set before starting the resource
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((_, _) =>
+            builder.OnBeforeStart((_, _) =>
             {
                 if (resourceBuilder.Resource.TryGetLastAnnotation<JavaScriptPackageManagerAnnotation>(out var packageManager))
                 {
@@ -631,7 +631,7 @@ public static IResourceBuilder<ViteAppResource> AddViteApp(this IDistributedAppl
 
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((@event, _) =>
+            builder.OnBeforeStart((@event, _) =>
             {
                 var developerCertificateService = @event.Services.GetRequiredService<IDeveloperCertificateService>();
 
@@ -985,7 +985,7 @@ private static void AddInstaller<TResource>(IResourceBuilder<TResource> resource
                 .ExcludeFromManifest()
                 .WithCertificateTrustScope(CertificateTrustScope.None);
 
-            resource.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((_, _) =>
+            resource.ApplicationBuilder.OnBeforeStart((_, _) =>
             {
                 // set the installer's working directory to match the resource's working directory
                 // and set the install command and args based on the resource's annotations

src/Aspire.Hosting.Keycloak/KeycloakResourceBuilderExtensions.cs

@@ -106,7 +106,7 @@ public static IResourceBuilder<KeycloakResource> AddKeycloak(
 
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((@event, cancellationToken) =>
+            builder.OnBeforeStart((@event, cancellationToken) =>
             {
                 var developerCertificateService = @event.Services.GetRequiredService<IDeveloperCertificateService>();
 

src/Aspire.Hosting.Maui/MauiOtlpExtensions.cs

@@ -115,7 +115,7 @@ private static OtlpDevTunnelConfigurationAnnotation CreateOtlpDevTunnelInfrastru
 
         // Manually allocate the stub endpoint so dev tunnel can start
         // Dev tunnels wait for ResourceEndpointsAllocatedEvent before starting
-        appBuilder.Eventing.Subscribe<BeforeStartEvent>((evt, ct) =>
+        appBuilder.OnBeforeStart((evt, ct) =>
         {
             var endpoint = stubResource.Annotations.OfType<EndpointAnnotation>().FirstOrDefault();
             if (endpoint is not null && endpoint.AllocatedEndpoint is null)

src/Aspire.Hosting.Python/PythonAppResourceBuilderExtensions.cs

@@ -312,7 +312,7 @@ public static IResourceBuilder<UvicornAppResource> AddUvicornApp(
 
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((@event, cancellationToken) =>
+            builder.OnBeforeStart((@event, cancellationToken) =>
             {
                 var developerCertificateService = @event.Services.GetRequiredService<IDeveloperCertificateService>();
 
@@ -510,7 +510,7 @@ private static IResourceBuilder<T> AddPythonAppCore<T>(
             // and the dependencies will be established based on which resources actually exist
             // Only do this in run mode since the installer and venv creator only run in run mode
             var resourceToSetup = resourceBuilder.Resource;
-            builder.Eventing.Subscribe<BeforeStartEvent>((evt, ct) =>
+            builder.OnBeforeStart((evt, ct) =>
             {
                 // Wire up wait dependencies for this resource based on which child resources exist
                 SetupDependencies(builder, resourceToSetup);
@@ -1346,7 +1346,7 @@ private static void AddInstaller<T>(IResourceBuilder<T> builder, bool install) w
                 installerBuilder.WithExplicitStart();
             }
 
-            builder.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((_, _) =>
+            builder.ApplicationBuilder.OnBeforeStart((_, _) =>
             {
                 // Set the installer's working directory to match the resource's working directory
                 // and set the install command and args based on the resource's annotations

src/Aspire.Hosting.Redis/RedisBuilderExtensions.cs

@@ -175,7 +175,7 @@ public static IResourceBuilder<RedisResource> AddRedis(
 
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((@event, cancellationToken) =>
+            builder.OnBeforeStart((@event, cancellationToken) =>
             {
                 var developerCertificateService = @event.Services.GetRequiredService<IDeveloperCertificateService>();
 
@@ -387,7 +387,7 @@ public static IResourceBuilder<RedisResource> WithRedisInsight(this IResourceBui
                 })
                 .ExcludeFromManifest();
 
-            builder.ApplicationBuilder.Eventing.Subscribe<BeforeStartEvent>((@event, cancellationToken) =>
+            builder.ApplicationBuilder.OnBeforeStart((@event, cancellationToken) =>
             {
                 var developerCertificateService = @event.Services.GetRequiredService<IDeveloperCertificateService>();
 

src/Aspire.Hosting.Yarp/YarpResourceExtensions.cs

@@ -55,7 +55,7 @@ public static IResourceBuilder<YarpResource> AddYarp(
 
         if (builder.ExecutionContext.IsRunMode)
         {
-            builder.Eventing.Subscribe<BeforeStartEvent>((@event, cancellationToken) =>
+            builder.OnBeforeStart((@event, cancellationToken) =>
             {
                 var developerCertificateService = @event.Services.GetRequiredService<IDeveloperCertificateService>();
 

src/Aspire.Hosting/ContainerRegistryResourceBuilderExtensions.cs

@@ -118,7 +118,7 @@ public static IResourceBuilder<ContainerRegistryResource> AddContainerRegistry(
     /// </summary>
     private static void SubscribeToAddRegistryTargetAnnotations(IDistributedApplicationBuilder builder, ContainerRegistryResource registry)
     {
-        builder.Eventing.Subscribe<BeforeStartEvent>((beforeStartEvent, cancellationToken) =>
+        builder.OnBeforeStart((beforeStartEvent, cancellationToken) =>
         {
             foreach (var resource in beforeStartEvent.Model.Resources)
             {