Allow to write custom code to validate an extensible object.

framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ExtensibleObjectValidator.cs

@@ -52,20 +52,47 @@ namespace Volo.Abp.ObjectExtending
                 return;
             }
 
-            foreach (var propertyInfo in objectExtensionInfo.GetProperties())
+            AddPropertyValidationErrors(
+                extensibleObject,
+                validationErrors,
+                objectValidationContext,
+                objectExtensionInfo
+            );
+
+            ExecuteCustomObjectValidationActions(
+                extensibleObject,
+                validationErrors,
+                objectValidationContext,
+                objectExtensionInfo
+            );
+        }
+
+        private static void AddPropertyValidationErrors(
+            IHasExtraProperties extensibleObject, 
+            List<ValidationResult> validationErrors,
+            ValidationContext objectValidationContext, 
+            ObjectExtensionInfo objectExtensionInfo)
+        {
+            var properties = objectExtensionInfo.GetProperties();
+            if (!properties.Any())
+            {
+                return;
+            }
+
+            foreach (var property in properties)
             {
-                if (propertyInfo.ValidationAttributes.Any())
+                if (property.ValidationAttributes.Any())
                 {
                     var propertyValidationContext = new ValidationContext(extensibleObject, objectValidationContext, null)
                     {
-                        DisplayName = propertyInfo.Name,
-                        MemberName = propertyInfo.Name
+                        DisplayName = property.Name,
+                        MemberName = property.Name
                     };
 
-                    foreach (var attribute in propertyInfo.ValidationAttributes)
+                    foreach (var attribute in property.ValidationAttributes)
                     {
                         var result = attribute.GetValidationResult(
-                            extensibleObject.GetProperty(propertyInfo.Name),
+                            extensibleObject.GetProperty(property.Name),
                             propertyValidationContext
                         );
                         if (result != null)
@@ -74,6 +101,46 @@ namespace Volo.Abp.ObjectExtending
                         }
                     }
                 }
+
+                if (property.Validators.Any())
+                {
+                    var context = new ObjectExtensionPropertyValidationContext(
+                        property,
+                        extensibleObject,
+                        validationErrors,
+                        objectValidationContext,
+                        extensibleObject.GetProperty(property.Name)
+                    );
+
+                    foreach (var validator in property.Validators)
+                    {
+                        validator(context);
+                    }
+                }
+            }
+        }
+
+        private static void ExecuteCustomObjectValidationActions(
+            IHasExtraProperties extensibleObject, 
+            List<ValidationResult> validationErrors,
+            ValidationContext objectValidationContext, 
+            ObjectExtensionInfo objectExtensionInfo)
+        {
+            if (!objectExtensionInfo.Validators.Any())
+            {
+                return;
+            }
+
+            var context = new ObjectExtensionValidationContext(
+                objectExtensionInfo,
+                extensibleObject,
+                validationErrors,
+                objectValidationContext
+            );
+
+            foreach (var validator in objectExtensionInfo.Validators)
+            {
+                validator(context);
             }
         }
     }

framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ObjectExtensionInfo.cs

@@ -17,11 +17,15 @@ namespace Volo.Abp.ObjectExtending
         [NotNull]
         public Dictionary<object, object> Configuration { get; }
 
+        [NotNull]
+        public List<Action<ObjectExtensionValidationContext>> Validators { get; }
+
         public ObjectExtensionInfo([NotNull] Type type)
         {
             Type = Check.AssignableTo<IHasExtraProperties>(type, nameof(type));
             Properties = new Dictionary<string, ObjectExtensionPropertyInfo>();
             Configuration = new Dictionary<object, object>();
+            Validators = new List<Action<ObjectExtensionValidationContext>>();
         }
 
         public virtual bool HasProperty(string propertyName)

framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ObjectExtensionPropertyInfo.cs

@@ -19,6 +19,9 @@ namespace Volo.Abp.ObjectExtending
         [NotNull]
         public List<ValidationAttribute> ValidationAttributes { get; }
 
+        [NotNull]
+        public List<Action<ObjectExtensionPropertyValidationContext>> Validators { get; }
+
         /// <summary>
         /// Indicates whether to check the other side of the object mapping
         /// if it explicitly defines the property. This property is used in;
@@ -47,6 +50,7 @@ namespace Volo.Abp.ObjectExtending
 
             Configuration = new Dictionary<object, object>();
             ValidationAttributes = new List<ValidationAttribute>();
+            Validators = new List<Action<ObjectExtensionPropertyValidationContext>>();
         }
     }
 }

framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ObjectExtensionPropertyValidationContext.cs

@@ -0,0 +1,61 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using JetBrains.Annotations;
+using Volo.Abp.Data;
+
+namespace Volo.Abp.ObjectExtending
+{
+    public class ObjectExtensionPropertyValidationContext
+    {
+        /// <summary>
+        /// Related property extension information.
+        /// </summary>
+        [NotNull]
+        public ObjectExtensionPropertyInfo ExtensionPropertyInfo { get; }
+
+        /// <summary>
+        /// Reference to the validating object.
+        /// </summary>
+        [NotNull]
+        public IHasExtraProperties ValidatingObject { get; }
+
+        /// <summary>
+        /// Add validation errors to this list.
+        /// </summary>
+        [NotNull]
+        public List<ValidationResult> ValidationErrors { get; }
+
+        /// <summary>
+        /// Validation context comes from the <see cref="IValidatableObject.Validate"/> method.
+        /// </summary>
+        [NotNull]
+        public ValidationContext ValidationContext { get; }
+
+        /// <summary>
+        /// The value of the validating property of the <see cref="ValidatingObject"/>.
+        /// </summary>
+        [CanBeNull]
+        public object Value { get; }
+
+        /// <summary>
+        /// Can be used to resolve services from the dependency injection container.
+        /// </summary>
+        [CanBeNull]
+        public IServiceProvider ServiceProvider => ValidationContext;
+
+        public ObjectExtensionPropertyValidationContext(
+            [NotNull] ObjectExtensionPropertyInfo objectExtensionPropertyInfo,
+            [NotNull] IHasExtraProperties validatingObject,
+            [NotNull] List<ValidationResult> validationErrors,
+            [NotNull] ValidationContext validationContext,
+            [CanBeNull] object value)
+        {
+            ExtensionPropertyInfo = Check.NotNull(objectExtensionPropertyInfo, nameof(objectExtensionPropertyInfo));
+            ValidatingObject = Check.NotNull(validatingObject, nameof(validatingObject));
+            ValidationErrors = Check.NotNull(validationErrors, nameof(validationErrors));
+            ValidationContext = Check.NotNull(validationContext, nameof(validationContext));
+            Value = value;
+        }
+    }
+}

framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ObjectExtensionValidationContext.cs

@@ -0,0 +1,53 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using JetBrains.Annotations;
+using Volo.Abp.Data;
+
+namespace Volo.Abp.ObjectExtending
+{
+    public class ObjectExtensionValidationContext
+    {
+        /// <summary>
+        /// Related object extension information.
+        /// </summary>
+        [NotNull]
+        public ObjectExtensionInfo ObjectExtensionInfo { get; }
+
+        /// <summary>
+        /// Reference to the validating object.
+        /// </summary>
+        [NotNull]
+        public IHasExtraProperties ValidatingObject { get; }
+
+        /// <summary>
+        /// Add validation errors to this list.
+        /// </summary>
+        [NotNull]
+        public List<ValidationResult> ValidationErrors { get; }
+
+        /// <summary>
+        /// Validation context comes from the <see cref="IValidatableObject.Validate"/> method.
+        /// </summary>
+        [NotNull]
+        public ValidationContext ValidationContext { get; }
+
+        /// <summary>
+        /// Can be used to resolve services from the dependency injection container.
+        /// </summary>
+        [CanBeNull]
+        public IServiceProvider ServiceProvider => ValidationContext;
+
+        public ObjectExtensionValidationContext(
+            [NotNull] ObjectExtensionInfo objectExtensionInfo,
+            [NotNull] IHasExtraProperties validatingObject,
+            [NotNull] List<ValidationResult> validationErrors,
+            [NotNull] ValidationContext validationContext)
+        {
+            ObjectExtensionInfo = Check.NotNull(objectExtensionInfo, nameof(objectExtensionInfo));
+            ValidatingObject = Check.NotNull(validatingObject, nameof(validatingObject));
+            ValidationErrors = Check.NotNull(validationErrors, nameof(validationErrors));
+            ValidationContext = Check.NotNull(validationContext, nameof(validationContext));
+        }
+    }
+}

framework/test/Volo.Abp.ObjectExtending.Tests/Volo/Abp/ObjectExtending/ExtensibleObjectValidator_Tests.cs

@@ -38,6 +38,43 @@ namespace Volo.Abp.ObjectExtending
                         {
 
                         });
+
+                        options.AddOrUpdateProperty<string>("Password", propertyInfo =>
+                        {
+                        });
+
+                        options.AddOrUpdateProperty<string>("PasswordRepeat", propertyInfo =>
+                        {
+                            propertyInfo.Validators.Add(context =>
+                            {
+                                if (context.ValidatingObject.HasProperty("Password"))
+                                {
+                                    if (context.ValidatingObject.GetProperty<string>("Password") !=
+                                        context.Value as string)
+                                    {
+                                        context.ValidationErrors.Add(
+                                            new ValidationResult(
+                                                "If you specify a password, then please correctly repeat it!",
+                                                new[] {"Password", "PasswordRepeat"}
+                                            )
+                                        );
+                                    }
+                                }
+                            });
+                        });
+
+                        options.Validators.Add(context =>
+                        {
+                            if (context.ValidatingObject.GetProperty<string>("Name") == "BadValue")
+                            {
+                                context.ValidationErrors.Add(
+                                    new ValidationResult(
+                                        "Name can not be 'BadValue', sorry :(",
+                                        new[] { "Name" }
+                                    )
+                                );
+                            }
+                        });
                     });
             });
         }
@@ -64,7 +101,7 @@ namespace Volo.Abp.ObjectExtending
             ExtensibleObjectValidator
                 .GetValidationErrors(
                     new ExtensiblePersonObject()
-                ).Count.ShouldBe(2); //Name & Age
+                ).Count.ShouldBe(2); // Name & Age
 
             ExtensibleObjectValidator
                 .GetValidationErrors(
@@ -75,7 +112,7 @@ namespace Volo.Abp.ObjectExtending
                             {"Address", new string('x', 256) }
                         }
                     }
-                ).Count.ShouldBe(3); //Name, Age & Address
+                ).Count.ShouldBe(3); // Name, Age & Address
 
             ExtensibleObjectValidator
                 .GetValidationErrors(
@@ -86,7 +123,7 @@ namespace Volo.Abp.ObjectExtending
                             {"Age", "42" }
                         }
                     }
-                ).Count.ShouldBe(1); //Name
+                ).Count.ShouldBe(1); // Name
 
             ExtensibleObjectValidator
                 .GetValidationErrors(
@@ -97,8 +134,34 @@ namespace Volo.Abp.ObjectExtending
                             {"Address", new string('x', 256) },
                             {"Age", "100" }
                         }
-            }
-                ).Count.ShouldBe(3); //Name, Age & Address
+                    }
+                ).Count.ShouldBe(3); // Name, Age & Address
+
+            ExtensibleObjectValidator
+                .GetValidationErrors(
+                    new ExtensiblePersonObject
+                    {
+                        ExtraProperties =
+                        {
+                            {"Name", "John"},
+                            {"Age", "42"},
+                            {"Password", "123"},
+                            {"PasswordRepeat", "1256"}
+                        }
+                    }
+                ).Count.ShouldBe(1); // PasswordRepeat != Password
+
+            ExtensibleObjectValidator
+                .GetValidationErrors(
+                    new ExtensiblePersonObject
+                    {
+                        ExtraProperties =
+                        {
+                            {"Name", "BadValue"},
+                            {"Age", "42"},
+                        }
+                    }
+                ).Count.ShouldBe(1); //Name is 'BadValue'!
         }
 
         private class ExtensiblePersonObject : ExtensibleObject