Register service with Interceptor, then register multiple decorator, auto apply Interceptor to the outermost decorator

src/Autofac/ServiceMiddlewareRegistrationExtensions.cs

@@ -105,6 +105,57 @@ public static void RegisterServiceMiddleware<TService>(this ContainerBuilder bui
         builder.RegisterServiceMiddleware(typeof(TService), new DelegateMiddleware(descriptor, phase, callback), insertionMode);
     }
 
+    /// <summary>
+    /// Register a resolve middleware for services providing a particular type.
+    /// </summary>
+    /// <param name="builder">The container builder.</param>
+    /// <param name="serviceType">The service type.</param>
+    /// <param name="phase">The phase of the pipeline the middleware should run at.</param>
+    /// <param name="callback">
+    /// A callback invoked to run your middleware.
+    /// This callback takes a <see cref="ResolveRequestContext"/>, containing the context for the resolve request, plus
+    /// a callback to invoke to continue the pipeline.
+    /// </param>
+    public static void RegisterServiceMiddleware(this ContainerBuilder builder, Type serviceType, PipelinePhase phase, Action<ResolveRequestContext, Action<ResolveRequestContext>> callback)
+    {
+        builder.RegisterServiceMiddleware(serviceType, AnonymousDescriptor, phase, MiddlewareInsertionMode.EndOfPhase, callback);
+    }
+
+    /// <summary>
+    /// Register a resolve middleware for services providing a particular type.
+    /// </summary>
+    /// <param name="builder">The container builder.</param>
+    /// <param name="serviceType">The service type.</param>
+    /// <param name="descriptor">A description for the middleware; this will show up in any resolve tracing.</param>
+    /// <param name="phase">The phase of the pipeline the middleware should run at.</param>
+    /// <param name="callback">
+    /// A callback invoked to run your middleware.
+    /// This callback takes a <see cref="ResolveRequestContext"/>, containing the context for the resolve request, plus
+    /// a callback to invoke to continue the pipeline.
+    /// </param>
+    public static void RegisterServiceMiddleware(this ContainerBuilder builder, Type serviceType, string descriptor, PipelinePhase phase, Action<ResolveRequestContext, Action<ResolveRequestContext>> callback)
+    {
+        builder.RegisterServiceMiddleware(serviceType, descriptor, phase, MiddlewareInsertionMode.EndOfPhase, callback);
+    }
+
+    /// <summary>
+    /// Register a resolve middleware for services providing a particular type.
+    /// </summary>
+    /// <param name="builder">The container builder.</param>
+    /// <param name="serviceType">The service type.</param>
+    /// <param name="descriptor">A description for the middleware; this will show up in any resolve tracing.</param>
+    /// <param name="phase">The phase of the pipeline the middleware should run at.</param>
+    /// <param name="callback">
+    /// A callback invoked to run your middleware.
+    /// This callback takes a <see cref="ResolveRequestContext"/>, containing the context for the resolve request, plus
+    /// a callback to invoke to continue the pipeline.
+    /// </param>
+    /// <param name="insertionMode">The insertion mode of the middleware (start or end of phase).</param>
+    public static void RegisterServiceMiddleware(this ContainerBuilder builder, Type serviceType, string descriptor, PipelinePhase phase, MiddlewareInsertionMode insertionMode, Action<ResolveRequestContext, Action<ResolveRequestContext>> callback)
+    {
+        builder.RegisterServiceMiddleware(serviceType, new DelegateMiddleware(descriptor, phase, callback), insertionMode);
+    }
+
     /// <summary>
     /// Register a resolve middleware for services providing a particular type.
     /// </summary>

test/Autofac.Specification.Test/Registration/RegistrationOnlyIfTests.cs

@@ -124,6 +124,46 @@ public void IfNotRegistered_CanHaveServiceMiddleware()
         Assert.True(middlewareInvoked);
     }
 
+    [Fact]
+    public void IfNotRegistered_EvaluatesServiceMiddleware()
+    {
+        var builder = new ContainerBuilder();
+        var middlewareInvoked = false;
+
+        builder.RegisterType<ServiceA>().As<IService>().IfNotRegistered(typeof(IService));
+
+        builder.RegisterServiceMiddleware(typeof(IService), PipelinePhase.ResolveRequestStart, (context, next) =>
+        {
+            next(context);
+            middlewareInvoked = true;
+        });
+
+        var container = builder.Build();
+        var result = container.Resolve<IService>();
+        Assert.True(middlewareInvoked);
+    }
+
+    [Fact]
+    public void IfNotRegistered_EvaluatesServiceMiddleware_WithDescriptor()
+    {
+        var builder = new ContainerBuilder();
+        var middlewareInvoked = false;
+
+        builder.RegisterType<ServiceA>().As<IService>().IfNotRegistered(typeof(IService));
+
+        const string descriptor = "custom-middleware";
+        builder.RegisterServiceMiddleware(typeof(IService), descriptor, PipelinePhase.ResolveRequestStart, (context, next) =>
+            {
+                next(context);
+                middlewareInvoked = true;
+            });
+
+        var container = builder.Build();
+
+        var result = container.Resolve<IService>();
+        Assert.True(middlewareInvoked);
+    }
+
     [Fact]
     public void IfNotRegistered_CanBeDecoratedByModuleWhenModuleRegistered1st()
     {