[Fixes #3503] Removing formatters on a given type only works on collections in MVC options

src/Microsoft.AspNet.Mvc.Abstractions/Filters/ResourceExecutingContext.cs

@@ -27,12 +27,12 @@ namespace Microsoft.AspNet.Mvc.Filters
         /// <summary>
         /// Gets or sets the list of <see cref="IInputFormatter"/> instances used by model binding.
         /// </summary>
-        public virtual IList<IInputFormatter> InputFormatters { get; set; }
+        public virtual FormatterCollection<IInputFormatter> InputFormatters { get; set; }
 
         /// <summary>
         /// Gets or sets the list of <see cref="IOutputFormatter"/> instances used to format the response.
         /// </summary>
-        public virtual IList<IOutputFormatter> OutputFormatters { get; set; }
+        public virtual FormatterCollection<IOutputFormatter> OutputFormatters { get; set; }
 
         /// <summary>
         /// Gets or sets the list of <see cref="IModelBinder"/> instances used by model binding.
@@ -40,7 +40,7 @@ namespace Microsoft.AspNet.Mvc.Filters
         public virtual IList<IModelBinder> ModelBinders { get; set; }
 
         /// <summary>
-        /// Gets or sets the result of the action to be executed. 
+        /// Gets or sets the result of the action to be executed.
         /// </summary>
         /// <remarks>
         /// Setting <see cref="Result"/> to a non-<c>null</c> value inside a resource filter will

src/Microsoft.AspNet.Mvc.Abstractions/Formatters/FormatterCollection.cs

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using System.Collections.ObjectModel;
 
 namespace Microsoft.AspNet.Mvc.Formatters
@@ -11,6 +12,23 @@ namespace Microsoft.AspNet.Mvc.Formatters
     /// <typeparam name="TFormatter">The type of formatters in the collection.</typeparam>
     public class FormatterCollection<TFormatter> : Collection<TFormatter>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FormatterCollection{TFormatter}"/> class that is empty.
+        /// </summary>
+        public FormatterCollection()
+            : base()
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FormatterCollection{TFormatter}"/> class
+        /// as a wrapper for the specified list.
+        /// </summary>
+        /// <param name="list">The list that is wrapped by the new collection.</param>
+        public FormatterCollection(IList<TFormatter> list)
+            : base(list)
+        {
+        }
 
         /// <summary>
         /// Removes all formatters of the specified type.

src/Microsoft.AspNet.Mvc.Core/Controllers/FilterActionInvoker.cs

@@ -49,7 +49,7 @@ namespace Microsoft.AspNet.Mvc.Controllers
 
         private ResultExecutingContext _resultExecutingContext;
         private ResultExecutedContext _resultExecutedContext;
-        
+
         public FilterActionInvoker(
             ActionContext actionContext,
             IReadOnlyList<IFilterProvider> filterProviders,
@@ -334,8 +334,10 @@ namespace Microsoft.AspNet.Mvc.Controllers
 
             var context = new ResourceExecutingContext(ActionContext, _filters);
 
-            context.InputFormatters = new CopyOnWriteList<IInputFormatter>(_inputFormatters);
-            context.OutputFormatters = new CopyOnWriteList<IOutputFormatter>(_outputFormatters);
+            context.InputFormatters = new FormatterCollection<IInputFormatter>(
+                new CopyOnWriteList<IInputFormatter>(_inputFormatters));
+            context.OutputFormatters = new FormatterCollection<IOutputFormatter>(
+                new CopyOnWriteList<IOutputFormatter>(_outputFormatters));
             context.ModelBinders = new CopyOnWriteList<IModelBinder>(_modelBinders);
             context.ValidatorProviders = new CopyOnWriteList<IModelValidatorProvider>(_modelValidatorProviders);
             context.ValueProviderFactories = new CopyOnWriteList<IValueProviderFactory>(_valueProviderFactories);
@@ -411,7 +413,7 @@ namespace Microsoft.AspNet.Mvc.Controllers
                     {
                         // Short-circuited by setting a result.
                         Logger.ResourceFilterShortCircuited(item.Filter);
-                        
+
                         await InvokeResultAsync(_resourceExecutingContext.Result);
 
                         _resourceExecutedContext = new ResourceExecutedContext(_resourceExecutingContext, _filters)

test/Microsoft.AspNet.Mvc.FunctionalTests/BasicTests.cs

@@ -7,6 +7,7 @@ using System.Net;
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Reflection;
+using System.Text;
 using System.Threading.Tasks;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Serialization;
@@ -346,5 +347,34 @@ namespace Microsoft.AspNet.Mvc.FunctionalTests
             // Assert
             Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
         }
+
+        [Fact]
+        public async Task ResourceFilter_CreatesSpecificInputAndOutputFormatters()
+        {
+            // Arrange
+            var input = "{\"fullName\":\"John Doe\"}";
+
+            // Act
+            var response = await Client.PostAsync(
+                "http://localhost/api/ActionUsingSpecificFormatters",
+                new StringContent(input, Encoding.UTF8, "application/json"));
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            Assert.Equal(input, await response.Content.ReadAsStringAsync());
+
+            // Make sure it does not affect other actions
+            //Arrange
+            input = "{\"FullName\":\"John Doe\"}";
+
+            // Act
+            response = await Client.PostAsync(
+                "http://localhost/api/ActionUsingGlobalFormatters",
+                new StringContent(input, Encoding.UTF8, "application/json"));
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            Assert.Equal(input, await response.Content.ReadAsStringAsync());
+        }
     }
 }

test/WebSites/BasicWebSite/Controllers/SpecificFormattersController.cs

@@ -0,0 +1,71 @@
+// 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.AspNet.Mvc;
+using Microsoft.AspNet.Mvc.Filters;
+using Microsoft.AspNet.Mvc.Formatters;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Serialization;
+
+namespace BasicWebSite
+{
+    public class SpecificFormattersController : Controller
+    {
+        [HttpPost("api/ActionUsingSpecificFormatters")]
+        [CamelCaseJsonFormatters]
+        public IActionResult ActionUsingSpecificFormatters([FromBody] Person person)
+        {
+            if (!ModelState.IsValid)
+            {
+                return HttpBadRequest(ModelState);
+            }
+
+            return Ok(person);
+        }
+
+        [HttpPost("api/ActionUsingGlobalFormatters")]
+        public IActionResult ActionUsingGlobalFormatters([FromBody] Person person)
+        {
+            if (!ModelState.IsValid)
+            {
+                return HttpBadRequest(ModelState);
+            }
+
+            return Ok(person);
+        }
+
+        public class Person
+        {
+            public string FullName { get; set; }
+        }
+
+        [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
+        private class CamelCaseJsonFormattersAttribute : Attribute, IResourceFilter
+        {
+            private readonly JsonSerializerSettings _serializerSettings;
+
+            public CamelCaseJsonFormattersAttribute()
+            {
+                _serializerSettings = new JsonSerializerSettings();
+                _serializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
+            }
+
+            public void OnResourceExecuted(ResourceExecutedContext context)
+            {
+            }
+
+            public void OnResourceExecuting(ResourceExecutingContext context)
+            {
+                // Do not modify existing json formatters as they would effect all controllers.
+                // Instead remove and add new formatters which only effects the controllers this
+                // attribute is decorated on.
+                context.InputFormatters.RemoveType<JsonInputFormatter>();
+                context.OutputFormatters.RemoveType<JsonOutputFormatter>();
+
+                context.InputFormatters.Add(new JsonInputFormatter(_serializerSettings));
+                context.OutputFormatters.Add(new JsonOutputFormatter(_serializerSettings));
+            }
+        }
+    }
+}