Default StatusCode for void return type changed to 200

src/Microsoft.AspNetCore.Mvc.ApiExplorer/DefaultApiDescriptionProvider.cs

@@ -377,8 +377,7 @@ private IReadOnlyList<ApiResponseType> GetApiResponseTypes(
 
             // Set the default status only when no status has already been set explicitly
             if (objectTypes.Count == 0
-                && type != null
-                && type != typeof(void))
+                && type != null)
             {
                 objectTypes[StatusCodes.Status200OK] = type;
             }

src/Microsoft.AspNetCore.Mvc.Core/AcceptedAtActionResult.cs

@@ -0,0 +1,94 @@
+// 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.Http;
+using Microsoft.AspNetCore.Mvc.Core;
+using Microsoft.AspNetCore.Routing;
+using Microsoft.AspNetCore.Mvc.Routing;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Net.Http.Headers;
+
+namespace Microsoft.AspNetCore.Mvc
+{
+    /// <summary>
+    /// An <see cref="ActionResult"/> that returns a Accepted (202) response with a Location header.
+    /// </summary>
+    public class AcceptedAtActionResult : ObjectResult
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AcceptedAtActionResult"/> with the values
+        /// provided.
+        /// </summary>
+        /// <param name="actionName">The name of the action to use for generating the URL.</param>
+        /// <param name="controllerName">The name of the controller to use for generating the URL.</param>
+        /// <param name="routeValues">The route data to use for generating the URL.</param>
+        /// <param name="value">The value to format in the entity body.</param>
+        public AcceptedAtActionResult(
+            string actionName,
+            string controllerName,
+            object routeValues,
+            object value)
+            : base(value)
+        {
+            ActionName = actionName;
+            ControllerName = controllerName;
+            RouteValues = routeValues == null ? null : new RouteValueDictionary(routeValues);
+            StatusCode = StatusCodes.Status202Accepted;
+        }
+
+        /// <summary>
+        /// Gets or sets the <see cref="IUrlHelper" /> used to generate URLs.
+        /// </summary>
+        public IUrlHelper UrlHelper { get; set; }
+
+        /// <summary>
+        /// Gets or sets the name of the action to use for generating the URL.
+        /// </summary>
+        public string ActionName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the name of the controller to use for generating the URL.
+        /// </summary>
+        public string ControllerName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the route data to use for generating the URL.
+        /// </summary>
+        public RouteValueDictionary RouteValues { get; set; }
+
+        /// <inheritdoc />
+        public override void OnFormatting(ActionContext context)
+        {
+            if (context == null)
+            {
+                throw new ArgumentNullException(nameof(context));
+            }
+
+            base.OnFormatting(context);
+
+            var request = context.HttpContext.Request;
+
+            var urlHelper = UrlHelper;
+            if (urlHelper == null)
+            {
+                var services = context.HttpContext.RequestServices;
+                urlHelper = services.GetRequiredService<IUrlHelperFactory>().GetUrlHelper(context);
+            }
+
+            var url = urlHelper.Action(
+                ActionName,
+                ControllerName,
+                RouteValues,
+                request.Scheme,
+                request.Host.ToUriComponent());
+
+            if (string.IsNullOrEmpty(url))
+            {
+                throw new InvalidOperationException(Resources.NoRoutesMatched);
+            }
+
+            context.HttpContext.Response.Headers[HeaderNames.Location] = url;
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Core/AcceptedAtRouteResult.cs

@@ -0,0 +1,90 @@
+// 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.Http;
+using Microsoft.AspNetCore.Mvc.Core;
+using Microsoft.AspNetCore.Routing;
+using Microsoft.AspNetCore.Mvc.Routing;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Net.Http.Headers;
+
+namespace Microsoft.AspNetCore.Mvc
+{
+    /// <summary>
+    /// An <see cref="ActionResult"/> that returns a Accepted (202) response with a Location header.
+    /// </summary>
+    public class AcceptedAtRouteResult : ObjectResult
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AcceptedAtRouteResult"/> class with the values
+        /// provided.
+        /// </summary>
+        /// <param name="routeValues">The route data to use for generating the URL.</param>
+        /// <param name="value">The value to format in the entity body.</param>
+        public AcceptedAtRouteResult(object routeValues, object value)
+            : this(routeName: null, routeValues: routeValues, value: value)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AcceptedAtRouteResult"/> class with the values
+        /// provided.
+        /// </summary>
+        /// <param name="routeName">The name of the route to use for generating the URL.</param>
+        /// <param name="routeValues">The route data to use for generating the URL.</param>
+        /// <param name="value">The value to format in the entity body.</param>
+        public AcceptedAtRouteResult(
+            string routeName,
+            object routeValues,
+            object value)
+            : base(value)
+        {
+            RouteName = routeName;
+            RouteValues = routeValues == null ? null : new RouteValueDictionary(routeValues);
+            StatusCode = StatusCodes.Status202Accepted;
+        }
+
+        /// <summary>
+        /// Gets or sets the <see cref="IUrlHelper" /> used to generate URLs.
+        /// </summary>
+        public IUrlHelper UrlHelper { get; set; }
+
+        /// <summary>
+        /// Gets or sets the name of the route to use for generating the URL.
+        /// </summary>
+        public string RouteName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the route data to use for generating the URL.
+        /// </summary>
+        public RouteValueDictionary RouteValues { get; set; }
+
+        /// <inheritdoc />
+        public override void OnFormatting(ActionContext context)
+        {
+            if (context == null)
+            {
+                throw new ArgumentNullException(nameof(context));
+            }
+
+            base.OnFormatting(context);
+
+            var urlHelper = UrlHelper;
+            if (urlHelper == null)
+            {
+                var services = context.HttpContext.RequestServices;
+                urlHelper = services.GetRequiredService<IUrlHelperFactory>().GetUrlHelper(context);
+            }
+
+            var url = urlHelper.Link(RouteName, RouteValues);
+
+            if (string.IsNullOrEmpty(url))
+            {
+                throw new InvalidOperationException(Resources.NoRoutesMatched);
+            }
+
+            context.HttpContext.Response.Headers[HeaderNames.Location] = url;
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.Core/AcceptedResult.cs

@@ -0,0 +1,80 @@
+// 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.Http;
+using Microsoft.Net.Http.Headers;
+
+namespace Microsoft.AspNetCore.Mvc
+{
+    /// <summary>
+    /// An <see cref="ActionResult"/> that returns an Accepted (202) response with a Location header.
+    /// </summary>
+    public class AcceptedResult : ObjectResult
+    {
+        private string _location;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AcceptedResult"/> class with the values
+        /// provided.
+        /// </summary>
+        /// <param name="location">The location at which the status of requested content can be monitored.</param>
+        /// <param name="value">The value to format in the entity body.</param>
+        public AcceptedResult(string location, object value)
+            : base(value)
+        {
+            Location = location;
+            StatusCode = StatusCodes.Status202Accepted;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AcceptedResult"/> class with the values
+        /// provided.
+        /// </summary>
+        /// <param name="location">The location at which the status of requested content can be monitored
+        /// It is an optional paramater and may be null</param>
+        /// <param name="value">The value to format in the entity body.</param>
+        public AcceptedResult(Uri location, object value)
+            : base(value)
+        {
+            if (location.IsAbsoluteUri)
+            {
+                Location = location.AbsoluteUri;
+            }
+            else
+            {
+                Location = location.GetComponents(UriComponents.SerializationInfoString, UriFormat.UriEscaped);
+            }
+
+            StatusCode = StatusCodes.Status202Accepted;
+        }
+
+        /// <summary>
+        /// Gets or sets the location at which the status of the requested content can be monitored.
+        /// </summary>
+        public string Location
+        {
+            get
+            {
+                return _location;
+            }
+            set
+            {              
+                _location = value;
+            }
+        }
+
+        /// <inheritdoc />
+        public override void OnFormatting(ActionContext context)
+        {
+            if (context == null)
+            {
+                throw new ArgumentNullException(nameof(context));
+            }
+
+            base.OnFormatting(context);
+
+            context.HttpContext.Response.Headers[HeaderNames.Location] = Location;
+        }
+    }
+}