Disable proxy for persistent container endpoints

Author: danegsta

src/Aspire.Hosting/ApplicationModel/EndpointAnnotation.cs

@@ -83,6 +83,11 @@ public int? Port
         }
     }
 
+    /// <summary>
+    /// Indicates the the port is set with an explicit value.
+    /// </summary>
+    public bool IsPortSet => _port != null;
+
     /// <summary>
     /// This is the port the resource is listening on. If the endpoint is used for the container, it is the container port.
     /// </summary>

src/Aspire.Hosting/ApplicationModel/ResourceExtensions.cs

@@ -320,7 +320,7 @@ public static int GetReplicaCount(this IResource resource)
     /// Gets the lifetime type of the container for the specified resource.
     /// Defaults to <see cref="ContainerLifetime.Session"/> if no <see cref="ContainerLifetimeAnnotation"/> is found.
     /// </summary>
-    /// <param name="resource">The resource to the get the ContainerLifetimeType for.</param>
+    /// <param name="resource">The resource to get the ContainerLifetimeType for.</param>
     /// <returns>
     /// The <see cref="ContainerLifetime"/> from the <see cref="ContainerLifetimeAnnotation"/> for the resource (if the annotation exists).
     /// Defaults to <see cref="ContainerLifetime.Session"/> if the annotation is not set.
@@ -335,6 +335,16 @@ internal static ContainerLifetime GetContainerLifetimeType(this IResource resour
         return ContainerLifetime.Session;
     }
 
+    /// <summary>
+    /// Determines whether a resource supports proxied endpoints/services. Returns true for non-container resources container resources with a lifetime other than <see cref="ContainerLifetime.Persistent"/>.
+    /// </summary>
+    /// <param name="resource">The resource to get proxy support for.</param>
+    /// <returns>True if the resource supports proxied endpoints/services, false otherwise.</returns>
+    internal static bool SupportsProxy(this IResource resource)
+    {
+        return !resource.IsContainer() || resource.GetContainerLifetimeType() != ContainerLifetime.Persistent;
+    }
+
     /// <summary>
     /// Get the top resource in the resource hierarchy.
     /// e.g. for a AzureBlobStorageResource, the top resource is the AzureStorageResource.

src/Aspire.Hosting/Dcp/ApplicationExecutor.cs

@@ -1015,7 +1015,7 @@ private void AddAllocatedEndpointInfo(IEnumerable<AppResource> resources)
                     throw new InvalidDataException($"Service {svc.Metadata.Name} should have valid address at this point");
                 }
 
-                if (!sp.EndpointAnnotation.IsProxied && svc.AllocatedPort is null)
+                if (!sp.EndpointAnnotation.IsProxied && svc.AllocatedPort == null)
                 {
                     throw new InvalidOperationException($"Service '{svc.Metadata.Name}' needs to specify a port for endpoint '{sp.EndpointAnnotation.Name}' since it isn't using a proxy.");
                 }
@@ -1040,12 +1040,25 @@ private void PrepareServices()
         // services produced by different resources).
         HashSet<string> serviceNames = [];
 
+        List<(IResource, EndpointAnnotation)> endpointsWithHostUnset = [];
+
         foreach (var sp in serviceProducers)
         {
             var endpoints = sp.Endpoints.ToArray();
 
             foreach (var endpoint in endpoints)
             {
+                if (!sp.ModelResource.SupportsProxy())
+                {
+                    // If the resource can't be proxied, we need to enforce that on the annotation
+                    endpoint.IsProxied = false;
+                }
+
+                if (sp.ModelResource.IsContainer() && !endpoint.IsProxied && !endpoint.IsPortSet && endpoint.TargetPort is int)
+                {
+                    endpointsWithHostUnset.Add((sp.ModelResource, endpoint));
+                }
+
                 var candidateServiceName = endpoints.Length == 1
                     ? GetObjectNameForResource(sp.ModelResource)
                     : GetObjectNameForResource(sp.ModelResource, endpoint.Name);
@@ -1070,6 +1083,15 @@ private void PrepareServices()
                 _appResources.Add(new ServiceAppResource(sp.ModelResource, svc, endpoint));
             }
         }
+
+        if (endpointsWithHostUnset.Any())
+        {
+            _logger.LogWarning("You have unproxied container endpoints without an explicit host port set. By default these endpoints will attempt to bind a host port that matches the container target port. This can lead to port conflicts if multiple containers are using the same target port(s). For containers running with a persistent lifetime or container endpoints with IsProxied disabled, we recommend specifying explicit host ports. For more information on container networking in .NET Aspire see: https://aka.ms/dotnet/aspire/container-networking");
+            foreach (var (resource, endpoint) in endpointsWithHostUnset)
+            {
+                _logger.LogInformation("'{EndpointName}' endpoint for '{ResourceName}' doesn't have a host port set. Attempting to bind host port '{TargetPort}'.", endpoint.Name, resource.Name, endpoint.TargetPort);
+            }
+        }
     }
 
     private void PrepareExecutables()
@@ -1626,10 +1648,6 @@ private async Task CreateContainerAsync(AppResource cr, ILogger resourceLogger,
 
         dcpContainerResource.Spec.Env = [];
 
-        var proxiedPorts = new List<EndpointAnnotation>();
-
-        var isPersistentContainer = modelContainerResource.GetContainerLifetimeType() == ContainerLifetime.Persistent;
-
         if (cr.ServicesProduced.Count > 0)
         {
             dcpContainerResource.Spec.Ports = new();
@@ -1657,25 +1675,9 @@ private async Task CreateContainerAsync(AppResource cr, ILogger resourceLogger,
                 }
 
                 dcpContainerResource.Spec.Ports.Add(portSpec);
-
-                if (isPersistentContainer)
-                {
-                    if (ea.IsProxied)
-                    {
-                        proxiedPorts.Add(ea);
-                    }
-                }
             }
         }
 
-        if (proxiedPorts.Count > 0)
-        {
-            _logger.LogWarning(
-                "'{ResourceName}' is configured with a persistent lifetime, but has proxied endpoints. The target port(s) ({TargetPorts}) will be exposed via a proxy while your App Host project is running, but may not otherwise be accessible between App Host runs. It is recommended to configure fixed unproxied endpoint ports for persistent containers. For more information on networking in .NET Aspire see: https://aka.ms/dotnet/aspire/networking",
-                modelContainerResource.Name,
-                string.Join(", ", proxiedPorts.Select(p => p.TargetPort)));
-        }
-
         if (modelContainerResource.TryGetEnvironmentVariables(out var containerEnvironmentVariables))
         {
             var context = new EnvironmentCallbackContext(_executionContext, config, cancellationToken);

src/Aspire.Hosting/ProjectResourceBuilderExtensions.cs

@@ -52,9 +52,9 @@ public static class ProjectResourceBuilderExtensions
     /// Example of adding a project to the application model.
     /// <code lang="csharp">
     /// var builder = DistributedApplication.CreateBuilder(args);
-    /// 
+    ///
     /// builder.AddProject&lt;Projects.InventoryService&gt;("inventoryservice");
-    /// 
+    ///
     /// builder.Build().Run();
     /// </code>
     /// </example>
@@ -67,7 +67,7 @@ public static class ProjectResourceBuilderExtensions
     }
 
     /// <summary>
-    /// Adds a .NET project to the application model. 
+    /// Adds a .NET project to the application model.
     /// </summary>
     /// <param name="builder">The <see cref="IDistributedApplicationBuilder"/>.</param>
     /// <param name="name">The name of the resource. This name will be used for service discovery when referenced in a dependency.</param>
@@ -85,9 +85,9 @@ public static class ProjectResourceBuilderExtensions
     /// Add a project to the app model via a project path.
     /// <code lang="csharp">
     /// var builder = DistributedApplication.CreateBuilder(args);
-    /// 
+    ///
     /// builder.AddProject("inventoryservice", @"..\InventoryService\InventoryService.csproj");
-    /// 
+    ///
     /// builder.Build().Run();
     /// </code>
     /// </example>
@@ -132,9 +132,9 @@ public static IResourceBuilder<ProjectResource> AddProject(this IDistributedAppl
     /// Example of adding a project to the application model.
     /// <code lang="csharp">
     /// var builder = DistributedApplication.CreateBuilder(args);
-    /// 
+    ///
     /// builder.AddProject&lt;Projects.InventoryService&gt;("inventoryservice", launchProfileName: "otherLaunchProfile");
-    /// 
+    ///
     /// builder.Build().Run();
     /// </code>
     /// </example>
@@ -170,9 +170,9 @@ public static IResourceBuilder<ProjectResource> AddProject(this IDistributedAppl
     /// Add a project to the app model via a project path.
     /// <code lang="csharp">
     /// var builder = DistributedApplication.CreateBuilder(args);
-    /// 
+    ///
     /// builder.AddProject("inventoryservice", @"..\InventoryService\InventoryService.csproj", launchProfileName: "otherLaunchProfile");
-    /// 
+    ///
     /// builder.Build().Run();
     /// </code>
     /// </example>
@@ -219,9 +219,9 @@ public static IResourceBuilder<ProjectResource> AddProject(this IDistributedAppl
     /// Example of adding a project to the application model.
     /// <code lang="csharp">
     /// var builder = DistributedApplication.CreateBuilder(args);
-    /// 
+    ///
     /// builder.AddProject&lt;Projects.InventoryService&gt;("inventoryservice", options => { options.LaunchProfileName = "otherLaunchProfile"; });
-    /// 
+    ///
     /// builder.Build().Run();
     /// </code>
     /// </example>
@@ -259,9 +259,9 @@ public static IResourceBuilder<ProjectResource> AddProject(this IDistributedAppl
     /// Add a project to the app model via a project path.
     /// <code lang="csharp">
     /// var builder = DistributedApplication.CreateBuilder(args);
-    /// 
+    ///
     /// builder.AddProject("inventoryservice", @"..\InventoryService\InventoryService.csproj", options => { options.LaunchProfileName = "otherLaunchProfile"; });
-    /// 
+    ///
     /// builder.Build().Run();
     /// </code>
     /// </example>
@@ -724,7 +724,7 @@ private static void SetAspNetCoreUrls(this IResourceBuilder<ProjectResource> bui
                 }
 
                 // If the endpoint is proxied, we will use localhost as the target host since DCP will be forwarding the traffic
-                var targetHost = e.EndpointAnnotation.IsProxied ? "localhost" : e.EndpointAnnotation.TargetHost;
+                var targetHost = e.EndpointAnnotation.IsProxied && builder.Resource.SupportsProxy() ? "localhost" : e.EndpointAnnotation.TargetHost;
 
                 aspnetCoreUrls.Append($"{e.Property(EndpointProperty.Scheme)}://{targetHost}:{e.Property(EndpointProperty.TargetPort)}");
                 first = false;

src/Aspire.Hosting/PublicAPI.Unshipped.txt

@@ -10,6 +10,7 @@ Aspire.Hosting.ApplicationModel.DockerfileBuildAnnotation.ContextPath.get -> str
 Aspire.Hosting.ApplicationModel.DockerfileBuildAnnotation.DockerfileBuildAnnotation(string! contextPath, string! dockerfilePath, string? stage) -> void
 Aspire.Hosting.ApplicationModel.DockerfileBuildAnnotation.DockerfilePath.get -> string!
 Aspire.Hosting.ApplicationModel.DockerfileBuildAnnotation.Stage.get -> string?
+Aspire.Hosting.ApplicationModel.EndpointAnnotation.IsPortSet.get -> bool
 Aspire.Hosting.ApplicationModel.EndpointNameAttribute
 Aspire.Hosting.ApplicationModel.EndpointNameAttribute.EndpointNameAttribute() -> void
 Aspire.Hosting.ApplicationModel.HealthReportSnapshot