Change ConcurrenyMIddleware service extensions method

src/Middleware/ConcurrencyLimiter/sample/Startup.cs

@@ -15,11 +15,11 @@ public class Startup
     {
         public void ConfigureServices(IServiceCollection services)
         {
-            services.AddConcurrencyLimiterStackPolicy(options =>
+            services.AddConcurrencyLimiter(options =>
             {
-                options.MaxConcurrentRequests = 2; 
+                options.MaxConcurrentRequests = 2;
                 options.RequestQueueLimit = 25;
-            });
+            }).AddStackPolicy();
         }
 
         public void Configure(IApplicationBuilder app, ILoggerFactory loggerFactory)

src/Middleware/ConcurrencyLimiter/src/ConcurrencyLimiterBuilder.cs

@@ -0,0 +1,24 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information
+
+using System;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Microsoft.AspNetCore.ConcurrencyLimiter
+{
+    public class ConcurrencyLimiterBuilder
+    {
+        public ConcurrencyLimiterBuilder(IServiceCollection services)
+        {
+            Services = services ?? throw new ArgumentNullException(nameof(services));
+        }
+
+        /// <summary>
+        /// Gets the <see cref="IServiceCollection"/> services are attached to.
+        /// </summary>
+        /// <value>
+        /// The <see cref="IServiceCollection"/> services are attached to.
+        /// </value>
+        public IServiceCollection Services { get; }
+    }
+}

src/Middleware/ConcurrencyLimiter/src/ConcurrencyLimiterBuilderExtensions.cs

@@ -0,0 +1,46 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information
+
+using System;
+using Microsoft.AspNetCore.ConcurrencyLimiter;
+
+namespace Microsoft.Extensions.DependencyInjection
+{
+    public static class ConcurrencyLimiterBuilderExtensions
+    {
+        /// <summary>
+        /// Tells <see cref="ConcurrencyLimiterMiddleware"/> to use a FIFO queue as its queueing strategy.
+        /// </summary>
+        /// <param name="builder"></param>
+        /// <returns></returns>
+        public static ConcurrencyLimiterBuilder AddQueuePolicy(this ConcurrencyLimiterBuilder builder)
+        {
+            builder.Services.AddSingleton<IQueuePolicy, QueuePolicy>();
+            return builder;
+        }
+
+        /// <summary>
+        /// Tells <see cref="ConcurrencyLimiterMiddleware"/> to use a LIFO stack as its queueing strategy.
+        /// </summary>
+        /// <param name="builder"></param>
+        /// <returns></returns>
+        public static ConcurrencyLimiterBuilder AddStackPolicy(this ConcurrencyLimiterBuilder builder)
+        {
+            builder.Services.AddSingleton<IQueuePolicy, StackPolicy>();
+            return builder;
+        }
+
+        /// <summary>
+        /// Tells <see cref="ConcurrencyLimiterMiddleware"/> to use a LIFO stack as its queueing strategy.
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection"/> to add services to.</param>
+        /// <param name="configure">Set the options used by the queue.
+        /// Mandatory, since <see cref="QueuePolicyOptions.MaxConcurrentRequests"></see> must be provided.</param>
+        /// <returns></returns>
+        public static IServiceCollection AddConcurrencyLimiterStackPolicy(this IServiceCollection services, Action<QueuePolicyOptions> configure)
+        {
+            services.Configure(configure);
+            return services;
+        }
+    }
+}

src/Middleware/ConcurrencyLimiter/src/ConcurrencyMiddlewareServiceCollectionExtensions.cs

@@ -0,0 +1,37 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using Microsoft.AspNetCore.ConcurrencyLimiter;
+
+namespace Microsoft.Extensions.DependencyInjection
+{
+    public static class ConcurrencyMiddlewareServiceCollectionExtensions
+    {
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection"/> to add services to.</param>
+        /// <param name="configure">Set the options used by the queue.
+        /// <returns></returns>
+        public static ConcurrencyLimiterBuilder AddConcurrencyLimiter(this IServiceCollection services, Action<QueuePolicyOptions> configure)
+        {
+            services.Configure(configure);
+
+            return new ConcurrencyLimiterBuilder(services);
+        }
+
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="services">The <see cref="IServiceCollection"/> to add services to.</param>
+        /// <param name="configure">Set the options used by the queue.
+        /// <returns></returns>
+        public static ConcurrencyLimiterBuilder AddConcurrencyLimiter(this IServiceCollection services, Action<QueuePolicyOptions, IServiceProvider> configure)
+        {
+            services.AddOptions<QueuePolicyOptions>().Configure(configure);
+
+            return new ConcurrencyLimiterBuilder(services);
+        }
+    }
+}

src/Middleware/ConcurrencyLimiter/src/QueuePolicies/QueuePolicyServiceCollectionExtensions.cs

@@ -18,7 +18,8 @@ public static class QueuePolicyServiceCollectionExtensions
         /// <param name="configure">Set the options used by the queue.
         /// Mandatory, since <see cref="QueuePolicyOptions.MaxConcurrentRequests"></see> must be provided.</param>
         /// <returns></returns>
-        public static IServiceCollection AddConcurrencyLimiterQueuePolicy(this IServiceCollection services, Action<QueuePolicyOptions> configure)
+        [Obsolete("This is obsolete and will be removed in a future version. Use AddConcurrencyLimiter(configure).AddQueuePolicy() instead")]
+        public static IServiceCollection AddQueuePolicy(this IServiceCollection services, Action<QueuePolicyOptions> configure)
         {
             services.Configure(configure);
             services.AddSingleton<IQueuePolicy, QueuePolicy>();
@@ -32,7 +33,8 @@ public static IServiceCollection AddConcurrencyLimiterQueuePolicy(this IServiceC
         /// <param name="configure">Set the options used by the queue.
         /// Mandatory, since <see cref="QueuePolicyOptions.MaxConcurrentRequests"></see> must be provided.</param>
         /// <returns></returns>
-        public static IServiceCollection AddConcurrencyLimiterStackPolicy(this IServiceCollection services, Action<QueuePolicyOptions> configure)
+        [Obsolete("This is obsolete and will be removed in a future version. Use AddConcurrencyLimiter(configure).AddStackPolicy() instead")]
+        public static IServiceCollection AddStackPolicy(this IServiceCollection services, Action<QueuePolicyOptions> configure)
         {
             services.Configure(configure);
             services.AddSingleton<IQueuePolicy, StackPolicy>();