Allow ValidationAttributes and IValidatableObjects to resolve services from the RequestServices provider by injecting it into the ValidationContext.

src/Microsoft.AspNet.Mvc.DataAnnotations/DataAnnotationsModelValidator.cs

@@ -82,7 +82,10 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
             var memberName = metadata.PropertyName ?? metadata.ModelType.Name;
             var container = validationContext.Container;
 
-            var context = new ValidationContext(container ?? validationContext.Model)
+            var context = new ValidationContext(
+                instance: container ?? validationContext.Model,
+                serviceProvider: validationContext.ActionContext?.HttpContext?.RequestServices,
+                items: null)
             {
                 DisplayName = metadata.GetDisplayName(),
                 MemberName = memberName

src/Microsoft.AspNet.Mvc.DataAnnotations/ValidatableObjectAdapter.cs

@@ -29,7 +29,11 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
                 throw new InvalidOperationException(message);
             }
 
-            var validationContext = new ValidationContext(validatable, serviceProvider: null, items: null);
+            var validationContext = new ValidationContext(
+                instance: validatable, 
+                serviceProvider: context.ActionContext?.HttpContext?.RequestServices, 
+                items: null);
+
             return ConvertResults(validatable.Validate(validationContext));
         }
 

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/Validation/DefaultObjectValidatorTests.cs

@@ -8,8 +8,10 @@ using System.Linq;
 #if DNXCORE50
 using System.Reflection;
 #endif
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Mvc.ModelBinding.Metadata;
 using Microsoft.AspNet.Testing;
+using Microsoft.Extensions.DependencyInjection;
 using Moq;
 using Xunit;
 
@@ -431,6 +433,49 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
             Assert.Equal("Error3", error.ErrorMessage);
         }
 
+        [Fact]
+        public void Validate_ComplexType_IValidatableObject_CanUseRequestServices()
+        {
+            // Arrange
+            var service = new Mock<IExampleService>();
+            service.Setup(x => x.DoSomething()).Verifiable();
+
+            var provider = new ServiceCollection().AddSingleton(service.Object).BuildServiceProvider();
+
+            var httpContext = new Mock<HttpContext>();
+            httpContext.SetupGet(x => x.RequestServices).Returns(provider);
+
+            var actionContext = new ActionContext { HttpContext = httpContext.Object };
+
+            var validatorProvider = CreateValidatorProvider();
+            var modelState = actionContext.ModelState;
+            var validationState = new ValidationStateDictionary();
+
+            var validator = CreateValidator();
+
+            var model = new Mock<IValidatableObject>();
+            model
+                .Setup(x => x.Validate(It.IsAny<ValidationContext>()))
+                .Callback((ValidationContext context) =>
+                {
+                    var receivedService = context.GetService<IExampleService>();
+                    Assert.Equal(service.Object, receivedService);
+                    receivedService.DoSomething();
+                })
+                .Returns(new List<ValidationResult>());
+
+            // Act
+            validator.Validate(
+                actionContext, 
+                validatorProvider, 
+                validationState, 
+                null, 
+                model.Object);
+
+            // Assert
+            service.Verify();
+        }
+
         [Fact]
         [ReplaceCulture]
         public void Validate_ComplexType_FieldsAreIgnored_Valid()
@@ -1071,5 +1116,10 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
                 }
             }
         }
+
+        public interface IExampleService
+        {
+            void DoSomething();
+        }
     }
 }

test/Microsoft.AspNet.Mvc.DataAnnotations.Test/DataAnnotationsModelValidatorTest.cs

@@ -5,7 +5,9 @@ using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Linq;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Mvc.DataAnnotations;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Localization;
 using Moq;
 using Xunit;
@@ -152,7 +154,7 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
         }
 
         [Fact]
-        public void Validatate_ValidationResultSuccess()
+        public void Validate_ValidationResultSuccess()
         {
             // Arrange
             var metadata = _metadataProvider.GetMetadataForType(typeof(string));
@@ -315,6 +317,50 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
             Assert.Equal("Longueur est invalide : 4", validationResult.Message);
         }
 
+        [Fact]
+        public void Validate_CanUseRequestServices_WithinValidationAttribute()
+        {
+            // Arrange
+            var service = new Mock<IExampleService>();
+            service.Setup(x => x.DoSomething()).Verifiable();
+
+            var provider = new ServiceCollection().AddSingleton(service.Object).BuildServiceProvider();
+
+            var httpContext = new Mock<HttpContext>();
+            httpContext.SetupGet(x => x.RequestServices).Returns(provider);
+
+            var attribute = new Mock<TestableValidationAttribute> { CallBase = true };
+            attribute
+                .Setup(p => p.IsValidPublic(It.IsAny<object>(), It.IsAny<ValidationContext>()))
+                .Callback((object o, ValidationContext context) =>
+                {
+                    var receivedService = context.GetService<IExampleService>();
+                    Assert.Equal(service.Object, receivedService);
+                    receivedService.DoSomething();
+                });
+
+            var validator = new DataAnnotationsModelValidator(
+                new ValidationAttributeAdapterProvider(),
+                attribute.Object,
+                stringLocalizer: null);
+
+            var validationContext = new ModelValidationContext(
+                actionContext: new ActionContext
+                {
+                    HttpContext = httpContext.Object
+                },
+                modelMetadata: _metadataProvider.GetMetadataForType(typeof(object)),
+                metadataProvider: _metadataProvider,
+                container: null,
+                model: new object());
+
+            // Act
+            var results = validator.Validate(validationContext);
+
+            // Assert
+            service.Verify();
+        }
+
         private const string LocalizationKey = "LocalizeIt";
 
         public static TheoryData Validate_AttributesIncludeValues
@@ -430,5 +476,10 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
         {
             public string Name { get; set; }
         }
+
+        public interface IExampleService
+        {
+            void DoSomething();
+        }
     }
 }