Support type cast in group by (#1182)

src/Microsoft.AspNetCore.OData/Query/Expressions/TransformationBinderBase.cs

@@ -10,6 +10,7 @@
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
+using Microsoft.AspNetCore.OData.Edm;
 using Microsoft.AspNetCore.OData.Query.Wrapper;
 using Microsoft.OData.Edm;
 using Microsoft.OData.ModelBuilder;
@@ -129,6 +130,9 @@ protected Expression BindAccessor(QueryNode node, Expression baseElement = null)
                 return BindSingleValueFunctionCallNode(node as SingleValueFunctionCallNode);
             case QueryNodeKind.Constant:
                 return BindConstantNode(node as ConstantNode);
+            case QueryNodeKind.SingleResourceCast:
+                var singleResourceCastNode = node as SingleResourceCastNode;
+                return BindSingleResourceCastNode(singleResourceCastNode, baseElement);
             default:
                 throw Error.NotSupported(SRResources.QueryNodeBindingNotSupported, node.Kind,
                     typeof(AggregationBinder).Name);
@@ -172,4 +176,15 @@ private Expression CreateOpenPropertyAccessExpression(SingleValueOpenPropertyAcc
                 nullExpression);
         }
     }
-}
+
+    private Expression BindSingleResourceCastNode(SingleResourceCastNode node, Expression baseElement = null)
+    {
+        IEdmStructuredTypeReference structured = node.StructuredTypeReference;
+        Contract.Assert(structured != null, "NS casts can contain only structured types");
+
+        Type clrType = Model.GetClrType(structured);
+
+        Expression source = Bind(node.Source);
+        return Expression.TypeAs(source, clrType);
+    }
+}

test/Microsoft.AspNetCore.OData.Tests/Models/ModelBuilderHelpers.cs

@@ -324,4 +324,44 @@ public static ODataModelBuilder Add_OrderCustomer_Binding(this ODataModelBuilder
         builder.EntitySet<Order>("Orders").HasRequiredBinding(o => o.Customer, "Customer");
         return builder;
     }
-}
+
+    public static ODataModelBuilder Add_Products_EntityType(this ODataModelBuilder builder)
+    {
+        var product = builder.EntityType<Product>();
+        product.HasKey(p => new { p.ProductID });
+        product.Property(p => p.ProductID);
+        product.Property(p => p.ProductName);
+        product.ComplexProperty(p => p.Category);
+        return builder;
+    }
+
+    public static ODataModelBuilder Add_DerivedProducts_EntityType(this ODataModelBuilder builder)
+    {
+        var derivedProduct = builder.EntityType<DerivedProduct>();
+        derivedProduct.DerivesFrom<Product>();
+        derivedProduct.Property(p => p.DerivedProductName);
+        return builder;
+    }
+
+    public static ODataModelBuilder Add_Categories_EntityType(this ODataModelBuilder builder)
+    {
+        var category = builder.ComplexType<Category>();
+        category.Property(c => c.CategoryID);
+        category.Property(c => c.CategoryName);
+        return builder;
+    }
+
+    public static ODataModelBuilder Add_DerivedCategories_EntityType(this ODataModelBuilder builder)
+    {
+        var derivedCategory = builder.ComplexType<DerivedCategory>();
+        derivedCategory.DerivesFrom<Category>();
+        derivedCategory.Property(c => c.DerivedCategoryName);
+        return builder;
+    }
+
+    public static ODataModelBuilder Add_Products_EntitySet(this ODataModelBuilder builder)
+    {
+        builder.EntitySet<Product>("Products");
+        return builder;
+    }
+}

test/Microsoft.AspNetCore.OData.Tests/Query/Expressions/AggregationBinderTests.cs

@@ -12,7 +12,9 @@
 using Microsoft.AspNetCore.OData.Abstracts;
 using Microsoft.AspNetCore.OData.Query;
 using Microsoft.AspNetCore.OData.Query.Expressions;
+using Microsoft.AspNetCore.OData.Tests.Commons;
 using Microsoft.AspNetCore.OData.Tests.Models;
+using Microsoft.OData;
 using Microsoft.OData.Edm;
 using Microsoft.OData.ModelBuilder;
 using Microsoft.OData.UriParser;
@@ -193,6 +195,46 @@ public void ClassicEFQueryShape()
             classicEF: true);
     }
 
+    [Fact]
+    public void NSCast_OnSingleEntity_GeneratesExpression_WithAsOperator()
+    {
+        var filters = VerifyQueryDeserialization(
+            "groupby((Microsoft.AspNetCore.OData.Tests.Models.Product/ProductName))",
+            ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = ProductName, Value = ($it As Product).ProductName, }, })"
+            + ".Select($it => new AggregationWrapper() {GroupByContainer = $it.Key.GroupByContainer, })");
+    }
+
+    [Theory]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.Product/ProductName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = ProductName, Value = ($it As Product).ProductName, }, })")]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/DerivedProductName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = DerivedProductName, Value = ($it As DerivedProduct).DerivedProductName, }, })")]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/Category/CategoryName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new NestedPropertyLastInChain() {Name = Category, NestedValue = new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = CategoryName, Value = ($it As DerivedProduct).Category.CategoryName, }, }, }, })")]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/Category/Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory/DerivedCategoryName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new NestedPropertyLastInChain() {Name = Category, NestedValue = new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = DerivedCategoryName, Value = (($it As DerivedProduct).Category As DerivedCategory).DerivedCategoryName, }, }, }, })")]
+    public void Inheritance_WithDerivedInstance(string filter, string expectedResult)
+    {
+        var filters = VerifyQueryDeserialization<DerivedProduct>(filter, expectedResult
+            + ".Select($it => new AggregationWrapper() {GroupByContainer = $it.Key.GroupByContainer, })");
+    }
+
+    [Theory]
+    [InlineData("groupby((ProductName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = ProductName, Value = $it.ProductName, }, })")]
+    [InlineData("groupby((Category/Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory/DerivedCategoryName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new NestedPropertyLastInChain() {Name = Category, NestedValue = new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = DerivedCategoryName, Value = ($it.Category As DerivedCategory).DerivedCategoryName, }, }, }, })")]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/DerivedProductName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = DerivedProductName, Value = ($it As DerivedProduct).DerivedProductName, }, })")]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/Category/CategoryName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new NestedPropertyLastInChain() {Name = Category, NestedValue = new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = CategoryName, Value = ($it As DerivedProduct).Category.CategoryName, }, }, }, })")]
+    [InlineData("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/Category/Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory/DerivedCategoryName))", ".GroupBy($it => new GroupByWrapper() {GroupByContainer = new NestedPropertyLastInChain() {Name = Category, NestedValue = new GroupByWrapper() {GroupByContainer = new LastInChain() {Name = DerivedCategoryName, Value = (($it As DerivedProduct).Category As DerivedCategory).DerivedCategoryName, }, }, }, })")]
+    public void Inheritance_WithBaseInstance(string filter, string expectedResult)
+    {
+        var filters = VerifyQueryDeserialization<Product>(filter, expectedResult
+            + ".Select($it => new AggregationWrapper() {GroupByContainer = $it.Key.GroupByContainer, })");
+    }
+
+    [Fact]
+    public void CastToNonDerivedType_Throws()
+    {
+        ExceptionAssert.Throws<ODataException>(
+            () => VerifyQueryDeserialization<Product>("groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory/CategoryName))"),
+            "Encountered invalid type cast. 'Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory' is not assignable from 'Microsoft.AspNetCore.OData.Tests.Models.Product'.");
+    }
+
     private Expression VerifyQueryDeserialization(string filter, string expectedResult = null, Action<ODataQuerySettings> settingsCustomizer = null, bool classicEF = false)
     {
         return VerifyQueryDeserialization<Product>(filter, expectedResult, settingsCustomizer, classicEF);
@@ -288,7 +330,7 @@ private IEdmModel GetModel<T>() where T : class
 
     private class AggregationBinderEFFake : AggregationBinder
     {
-        internal AggregationBinderEFFake(ODataQuerySettings settings, IAssemblyResolver assembliesResolver, Type elementType, IEdmModel model, TransformationNode transformation) 
+        internal AggregationBinderEFFake(ODataQuerySettings settings, IAssemblyResolver assembliesResolver, Type elementType, IEdmModel model, TransformationNode transformation)
             : base(settings, assembliesResolver, elementType, model, transformation)
         {
         }
@@ -298,4 +340,4 @@ internal override bool IsClassicEF(IQueryable query)
             return true;
         }
     }
-}
+}

test/Microsoft.AspNetCore.OData.Tests/Query/Query/ApplyQueryOptionTest.cs

@@ -1600,6 +1600,150 @@ public void SortOnNestedDynamicPropertyWorks()
         }
     }
 
+    public static List<Product> ProductApplyForTypeCastTestData
+    {
+        get
+        {
+            List<Product> productList = new List<Product>();
+
+            Product p1 = new DerivedProduct
+            {
+                ProductID = 1,
+                ProductName = "Product 1",
+                DerivedProductName = "Product A",
+                Category = new DerivedCategory
+                {
+                    CategoryID = 1,
+                    CategoryName = "Category 1",
+                    DerivedCategoryName = "Category A",
+                },
+            };
+            productList.Add(p1);
+            Product p2 = new DerivedProduct
+            {
+                ProductID = 2,
+                ProductName = "Product 1",
+                DerivedProductName = "Product A",
+                Category = new DerivedCategory
+                {
+                    CategoryID = 1,
+                    CategoryName = "Category 1",
+                    DerivedCategoryName = "Category A",
+                },
+            };
+            productList.Add(p2);
+            Product p3 = new DerivedProduct
+            {
+                ProductID = 3,
+                ProductName = "Product 2",
+                DerivedProductName = "Product B",
+                Category = new DerivedCategory
+                {
+                    CategoryID = 2,
+                    CategoryName = "Category 2",
+                    DerivedCategoryName = "Category B",
+                },
+            };
+            productList.Add(p3);
+
+            return productList;
+        }
+    }
+
+    public static TheoryDataSet<string, List<Dictionary<string, object>>> ProductTestAppliesForTypeCast
+    {
+        get
+        {
+            return new TheoryDataSet<string, List<Dictionary<string, object>>>
+                {
+                    {
+                        "groupby((Microsoft.AspNetCore.OData.Tests.Models.Product/ProductName))",
+                        new List<Dictionary<string, object>>
+                        {
+                            new Dictionary<string, object> { {"ProductName", "Product 1"} },
+                            new Dictionary<string, object> { {"ProductName", "Product 2"} }
+                        }
+                    },
+                    {
+                        "groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/DerivedProductName))",
+                        new List<Dictionary<string, object>>
+                        {
+                            new Dictionary<string, object> { { "DerivedProductName", "Product A"} },
+                            new Dictionary<string, object> { { "DerivedProductName", "Product B"} }
+                        }
+                    },
+                    {
+                        "groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/Category/CategoryName))",
+                        new List<Dictionary<string, object>>
+                        {
+                            new Dictionary<string, object> { { "Category/CategoryName", "Category 1" } },
+                            new Dictionary<string, object> { { "Category/CategoryName", "Category 2" } }
+                        }
+                    },
+                    {
+                        "groupby((Category/Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory/DerivedCategoryName))",
+                        new List<Dictionary<string, object>>
+                        {
+                            new Dictionary<string, object> { { "Category/DerivedCategoryName", "Category A" } },
+                            new Dictionary<string, object> { { "Category/DerivedCategoryName", "Category B" } }
+                        }
+                    },
+                    {
+                        "groupby((Microsoft.AspNetCore.OData.Tests.Models.DerivedProduct/Category/Microsoft.AspNetCore.OData.Tests.Models.DerivedCategory/DerivedCategoryName))",
+                        new List<Dictionary<string, object>>
+                        {
+                            new Dictionary<string, object> { { "Category/DerivedCategoryName", "Category A" } },
+                            new Dictionary<string, object> { { "Category/DerivedCategoryName", "Category B" } }
+                        }
+                    }
+                };
+        }
+    }
+
+    [Theory]
+    [MemberData(nameof(ProductTestAppliesForTypeCast))]
+    public void ApplyTo_Returns_Correct_Queryable_ForTypeCast(string apply, List<Dictionary<string, object>> aggregation)
+    {
+        // Arrange
+        var model = new ODataModelBuilder()
+                        .Add_Products_EntityType()
+                        .Add_DerivedProducts_EntityType()
+                        .Add_Categories_EntityType()
+                        .Add_DerivedCategories_EntityType()
+                        .Add_Products_EntitySet()
+                        .GetEdmModel();
+        var context = new ODataQueryContext(model, typeof(Product)) { RequestContainer = new MockServiceProvider() };
+        var queryOptionParser = new ODataQueryOptionParser(
+            context.Model,
+            context.ElementType,
+            context.NavigationSource,
+            new Dictionary<string, string> { { "$apply", apply } });
+        var applyOption = new ApplyQueryOption(apply, context, queryOptionParser);
+        IEnumerable<Product> products = ProductApplyForTypeCastTestData;
+
+        // Act
+        IQueryable queryable = applyOption.ApplyTo(products.AsQueryable(), new ODataQuerySettings { HandleNullPropagation = HandleNullPropagationOption.True });
+
+        // Assert
+        Assert.NotNull(queryable);
+        var actualProducts = Assert.IsAssignableFrom<IEnumerable<DynamicTypeWrapper>>(queryable).ToList();
+
+        Assert.Equal(aggregation.Count(), actualProducts.Count());
+
+        var aggEnum = actualProducts.GetEnumerator();
+
+        foreach (var expected in aggregation)
+        {
+            aggEnum.MoveNext();
+            var agg = aggEnum.Current;
+            foreach (var key in expected.Keys)
+            {
+                object value = GetValue(agg, key);
+                Assert.Equal(expected[key], value);
+            }
+        }
+    }
+
     private object GetValue(DynamicTypeWrapper wrapper, string path)
     {
         var parts = path.Split('/');
@@ -1647,4 +1791,4 @@ public IQueryable<Customer> Get()
     {
         return _customers.AsQueryable();
     }
-}
+}