Added ability to resolve target port

src/Aspire.Hosting.Dapr/CommandLineBuilder.cs

@@ -6,9 +6,9 @@
 
 namespace Aspire.Hosting.Dapr;
 
-internal delegate IEnumerable<string> CommandLineArgBuilder();
+internal delegate IEnumerable<object> CommandLineArgBuilder();
 
-internal sealed record CommandLine(string FileName, IEnumerable<string> Arguments)
+internal sealed record CommandLine(string FileName, IEnumerable<object> Arguments)
 {
     public string ArgumentString
     {
@@ -178,6 +178,26 @@ private static CommandLineArgBuilder ModelNamedStringArg(string name, string val
         };
     }
 
+    public static CommandLineArgBuilder ModelNamedObjectArg(string name, object value)
+    {
+        return () =>
+        {
+            return [name, value];
+        };
+    }
+
+    public static CommandLineArgBuilder ModelNamedObjectArg<T>(string name, object value, bool assignValue = false) where T : struct
+    {
+        return () =>
+        {
+            string? stringValue = Convert.ToString(value, CultureInfo.InvariantCulture);
+
+            return stringValue is not null
+                ? ModelNamedStringArg(name, stringValue, assignValue)()
+                : Enumerable.Empty<string>();
+        };
+    }
+
     public static CommandLineArgBuilder PostOptionsArgs(params CommandLineArgBuilder[] args)
     {
         return PostOptionsArgs(null, args);
@@ -190,7 +210,7 @@ public static CommandLineArgBuilder PostOptionsArgs(string? separator, params Co
 
     public static CommandLineArgBuilder PostOptionsArgs(string? separator, IEnumerable<CommandLineArgBuilder> args)
     {
-        IEnumerable<string> GeneratePostOptionsArgs()
+        IEnumerable<object> GeneratePostOptionsArgs()
         {
             bool postOptions = false;
 

src/Aspire.Hosting.Dapr/DaprDistributedApplicationLifecycleHook.cs

@@ -94,10 +94,10 @@ public async Task BeforeStartAsync(DistributedApplicationModel appModel, Cancell
             }
 
             var daprAppPortArg = (int? port) => ModelNamedArg("--app-port", port);
-            var daprGrpcPortArg = (string? port) => ModelNamedArg("--dapr-grpc-port", port);
-            var daprHttpPortArg = (string? port) => ModelNamedArg("--dapr-http-port", port);
-            var daprMetricsPortArg = (string? port) => ModelNamedArg("--metrics-port", port);
-            var daprProfilePortArg = (string? port) => ModelNamedArg("--profile-port", port);
+            var daprGrpcPortArg = (object port) => ModelNamedObjectArg("--dapr-grpc-port", port);
+            var daprHttpPortArg = (object port) => ModelNamedObjectArg("--dapr-http-port", port);
+            var daprMetricsPortArg = (object port) => ModelNamedObjectArg("--metrics-port", port);
+            var daprProfilePortArg = (object port) => ModelNamedObjectArg("--profile-port", port);
             var daprAppChannelAddressArg = (string? address) => ModelNamedArg("--app-channel-address", address);
 
             var appId = sidecarOptions?.AppId ?? resource.Name;
@@ -182,13 +182,21 @@ public async Task BeforeStartAsync(DistributedApplicationModel appModel, Cancell
                             }
                         }
 
-                        updatedArgs.AddRange(daprGrpcPortArg($"{{{{- portForServing \"{daprCliResourceName}_grpc\" -}}}}")());
-                        updatedArgs.AddRange(daprHttpPortArg($"{{{{- portForServing \"{daprCliResourceName}_http\" -}}}}")());
-                        updatedArgs.AddRange(daprMetricsPortArg($"{{{{- portForServing \"{daprCliResourceName}_metrics\" -}}}}")());
+                        var grpc = daprCli.GetEndpoint("grpc");
+                        var http = daprCli.GetEndpoint("http");
+                        var metrics = daprCli.GetEndpoint("metrics");
+
+                        updatedArgs.AddRange(daprGrpcPortArg(grpc.Property(EndpointProperty.TargetPort))());
+                        updatedArgs.AddRange(daprHttpPortArg(http.Property(EndpointProperty.TargetPort))());
+                        updatedArgs.AddRange(daprMetricsPortArg(metrics.Property(EndpointProperty.TargetPort))());
+
                         if (sidecarOptions?.EnableProfiling == true)
                         {
-                            updatedArgs.AddRange(daprProfilePortArg($"{{{{- portForServing \"{daprCliResourceName}_profile\" -}}}}")());
+                            var profiling = daprCli.GetEndpoint("profiling");
+
+                            updatedArgs.AddRange(daprProfilePortArg(profiling.Property(EndpointProperty.TargetPort))());
                         }
+
                         if (sidecarOptions?.AppChannelAddress is null && httpEndPoint is not null)
                         {
                             updatedArgs.AddRange(daprAppChannelAddressArg(httpEndPoint.Host)());

src/Aspire.Hosting/ApplicationModel/AllocatedEndpoint.cs

@@ -18,7 +18,8 @@ public class AllocatedEndpoint
     /// <param name="address">The IP address of the endpoint.</param>
     /// <param name="containerHostAddress">The address of the container host.</param>
     /// <param name="port">The port number of the endpoint.</param>
-    public AllocatedEndpoint(EndpointAnnotation endpoint, string address, int port, string? containerHostAddress = null)
+    /// <param name="dcpServiceName">The name of the DCP service.</param>
+    public AllocatedEndpoint(EndpointAnnotation endpoint, string address, int port, string? containerHostAddress = null, string? dcpServiceName = null)
     {
         ArgumentNullException.ThrowIfNull(endpoint);
         ArgumentOutOfRangeException.ThrowIfLessThan(port, 1, nameof(port));
@@ -28,6 +29,7 @@ public AllocatedEndpoint(EndpointAnnotation endpoint, string address, int port,
         Address = address;
         ContainerHostAddress = containerHostAddress;
         Port = port;
+        DcpServiceName = dcpServiceName;
     }
 
     /// <summary>
@@ -65,6 +67,11 @@ public AllocatedEndpoint(EndpointAnnotation endpoint, string address, int port,
     /// </summary>
     public string UriString => $"{UriScheme}://{EndPointString}";
 
+    /// <summary>
+    /// The associated service name created in DCP for this endpoint.
+    /// </summary>
+    public string? DcpServiceName { get; }
+
     /// <summary>
     /// Returns a string representation of the allocated endpoint URI.
     /// </summary>

src/Aspire.Hosting/ApplicationModel/EndpointAnnotation.cs

@@ -26,9 +26,8 @@ public sealed class EndpointAnnotation : IResourceAnnotation
     /// <param name="port">Desired port for the service.</param>
     /// <param name="targetPort">This is the port the resource is listening on. If the endpoint is used for the container, it is the container port.</param>
     /// <param name="isExternal">Indicates that this endpoint should be exposed externally at publish time.</param>
-    /// <param name="env">The name of the environment variable that will be set to the port number of this endpoint.</param>
     /// <param name="isProxied">Specifies if the endpoint will be proxied by DCP. Defaults to true.</param>
-    public EndpointAnnotation(ProtocolType protocol, string? uriScheme = null, string? transport = null, string? name = null, int? port = null, int? targetPort = null, bool? isExternal = null, string? env = null, bool isProxied = true)
+    public EndpointAnnotation(ProtocolType protocol, string? uriScheme = null, string? transport = null, string? name = null, int? port = null, int? targetPort = null, bool? isExternal = null, bool isProxied = true)
     {
         // If the URI scheme is null, we'll adopt either udp:// or tcp:// based on the
         // protocol. If the name is null, we'll use the URI scheme as the default. This
@@ -47,7 +46,6 @@ public EndpointAnnotation(ProtocolType protocol, string? uriScheme = null, strin
         Port = port;
         TargetPort = targetPort ?? port;
         IsExternal = isExternal ?? false;
-        EnvironmentVariable = env;
         IsProxied = isProxied;
     }
 
@@ -93,11 +91,6 @@ public string Transport
     /// </summary>
     public bool IsExternal { get; set; }
 
-    /// <summary>
-    /// The name of the environment variable that will be set to the port number of this endpoint.
-    /// </summary>
-    public string? EnvironmentVariable { get; set; }
-
     /// <summary>
     /// Indicates that this endpoint should be managed by DCP. This means it can be replicated and use a different port internally than the one publicly exposed.
     /// Setting to false means the endpoint will be handled and exposed by the resource.

src/Aspire.Hosting/ApplicationModel/EndpointReference.cs

@@ -34,6 +34,11 @@ public sealed class EndpointReference : IManifestExpressionProvider, IValueProvi
     /// </summary>
     public bool IsAllocated => _isAllocated ??= GetAllocatedEndpoint() is not null;
 
+    /// <summary>
+    /// Gets a value indicating whether the endpoint exists.
+    /// </summary>
+    public bool Exists => GetEndpointAnnotation() is not null;
+
     string IManifestExpressionProvider.ValueExpression => GetExpression();
 
     ValueTask<string?> IValueProvider.GetValueAsync(CancellationToken cancellationToken) => new(Url);
@@ -49,6 +54,7 @@ internal string GetExpression(EndpointProperty property = EndpointProperty.Url)
             EndpointProperty.Host or EndpointProperty.IPV4Host => "host",
             EndpointProperty.Port => "port",
             EndpointProperty.Scheme => "scheme",
+            EndpointProperty.TargetPort => "targetPort",
             _ => throw new InvalidOperationException($"The property '{property}' is not supported for the endpoint '{EndpointName}'.")
         };
 
@@ -72,6 +78,11 @@ public EndpointReferenceExpression Property(EndpointProperty property)
     /// </summary>
     public int Port => AllocatedEndpoint.Port;
 
+    /// <summary>
+    /// Gets the target port for this endpoint. If the port is dynamically allocated, this will return <see langword="null"/>.
+    /// </summary>
+    public int? TargetPort => EndpointAnnotation.TargetPort;
+
     /// <summary>
     /// Gets the host for this endpoint.
     /// </summary>
@@ -85,14 +96,14 @@ public EndpointReferenceExpression Property(EndpointProperty property)
     /// <summary>
     /// Gets the scheme for this endpoint.
     /// </summary>
-    public string Scheme => AllocatedEndpoint.UriScheme;
+    public string Scheme => EndpointAnnotation.UriScheme;
 
     /// <summary>
     /// Gets the URL for this endpoint.
     /// </summary>
     public string Url => AllocatedEndpoint.UriString;
 
-    private AllocatedEndpoint AllocatedEndpoint =>
+    internal AllocatedEndpoint AllocatedEndpoint =>
         GetAllocatedEndpoint()
         ?? throw new InvalidOperationException($"The endpoint `{EndpointName}` is not allocated for the resource `{Resource.Name}`.");
 
@@ -158,7 +169,7 @@ public class EndpointReferenceExpression(EndpointReference endpointReference, En
     /// Gets the value of the property of the endpoint.
     /// </summary>
     /// <param name="cancellationToken">A <see cref="CancellationToken"/>.</param>
-    /// <returns>A <see cref="String"/> containing the selected <see cref="EndpointProperty"/> value.</returns>
+    /// <returns>A <see cref="string"/> containing the selected <see cref="EndpointProperty"/> value.</returns>
     /// <exception cref="InvalidOperationException">Throws when the selected <see cref="EndpointProperty"/> enumeration is not known.</exception>
     public ValueTask<string?> GetValueAsync(CancellationToken cancellationToken) => Property switch
     {
@@ -167,9 +178,27 @@ public class EndpointReferenceExpression(EndpointReference endpointReference, En
         EndpointProperty.IPV4Host => new("127.0.0.1"),
         EndpointProperty.Port => new(Endpoint.Port.ToString(CultureInfo.InvariantCulture)),
         EndpointProperty.Scheme => new(Endpoint.Scheme),
+        EndpointProperty.TargetPort => new(ComputeTargetPort()),
         _ => throw new InvalidOperationException($"The property '{Property}' is not supported for the endpoint '{Endpoint.EndpointName}'.")
     };
 
+    private string? ComputeTargetPort()
+    {
+        // We have a target port, so we can return it directly.
+        if (Endpoint.TargetPort is int port)
+        {
+            return port.ToString(CultureInfo.InvariantCulture);
+        }
+
+        // There is no way to resolve the value of the target port until runtime. Even then, replicas make this very complex because
+        // the target port is not known until the replica is allocated.
+        // Instead, we return an expression that will be resolved at runtime by the orchestrator.
+        return $$$"""{{- portForServing "{{{DcpServiceName}}}" -}}""";
+    }
+
+    private string DcpServiceName => Endpoint.AllocatedEndpoint.DcpServiceName
+        ?? throw new InvalidOperationException("The endpoint does not have an associated service name in the orchestrator.");
+
     IEnumerable<object> IValueWithReferences.References => [Endpoint];
 }
 
@@ -197,5 +226,9 @@ public enum EndpointProperty
     /// <summary>
     /// The scheme of the endpoint.
     /// </summary>
-    Scheme
+    Scheme,
+    /// <summary>
+    /// The target port of the endpoint.
+    /// </summary>
+    TargetPort
 }