Query By SubProperty

[luizfbicalho]

I created this two classes

`

public class Child
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }

    [Required]
    [StringLength(255)]
    [DataType("varchar")]
    public string Description { get; set; }

    public virtual Parent Parent { get; set; }
}`

And

`

 public class Parent
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }

    [Required]
    [StringLength(255)]
    [DataType("varchar")]
    public string Description { get; set; }
}`

and created a controller with two methods

`

    [HttpGet("Grid")]
    public IActionResult Grid()
    {
        try
        {
            var result = Context.Children.AsQueryable().ToDataSourceResult(999, 0, new List<Sort>(), new Filter
            {
                Filters = new Filter[] { new Filter { Field = "Description", Operator = "contains",
                    Value = "4" } },
                Logic = "and"
            });
            return Ok(result);
        }
        catch (Exception ex)
        {
            return BadRequest(ex.Message);
        }
    }
    [HttpGet("GridParent")]
    public IActionResult GridParent( )
    {
        try
        {
            var result = Context.Children.Include(x=>x.Parent).AsQueryable().ToDataSourceResult(999, 0, new List<Sort>(), new Filter
            {
                Filters = new Filter[] { new Filter { Field = "Parent.Description", Operator = "contains",
                    Value = "4" } },
                Logic = "and"
            });
            return Ok(result);
        }catch (Exception ex)
        {
            return BadRequest(ex.Message);
        }
    }

`

The first method works fine but in the second I get the Error
No 'parent' is in scope

How can I make this kind of filter to work?

[linmasaki]

I tested the code that you provided and then took no errors in my scenario. So give me a little time to find the error reason and upload a sample to you. Thanks for your response.

[AllanVini47]

I have the same problem.

error:

`

System.InvalidOperationException: The LINQ expression 'Where<TransparentIdentifier<IndicadorUnidade, Unidade>>(
source: Join<IndicadorUnidade, Unidade, Nullable, TransparentIdentifier<IndicadorUnidade, Unidade>>(
outer: DbSet,
inner: DbSet,
outerKeySelector: (i) => Property<Nullable>(i, "UnidadeId"),
innerKeySelector: (u) => Property<Nullable>(u, "Id"),
resultSelector: (o, i) => new TransparentIdentifier<IndicadorUnidade, Unidade>(
Outer = o,
Inner = i
)),
predicate: (i) => i.Inner.Descricao != null && i.Inner.Descricao.ToString().Contains("2"))' could not be translated. Either rewrite the query in a form that can be translated, or switch to client evaluation explicitly by inserting a call to either AsEnumerable(), AsAsyncEnumerable(), ToList(), or ToListAsync(). See https://go.microsoft.com/fwlink/?linkid=2101038 for more information.
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.g__CheckTranslated|8_0(ShapedQueryExpression translated, <>c__DisplayClass8_0& )
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryCompilationContext.CreateQueryExecutor[TResult](Expression query)
at Microsoft.EntityFrameworkCore.Storage.Database.CompileQuery[TResult](Expression query, Boolean async)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.CompileQueryCore[TResult](IDatabase database, Expression query, IModel model, Boolean async)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass9_01.<Execute>b__0() at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQueryCore[TFunc](Object cacheKey, Func1 compiler)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query)
at Kendo.DynamicLinqCore.QueryableExtensions.ToDataSourceResult[T](IQueryable1 queryable, Int32 take, Int32 skip, IEnumerable1 sort, Filter filter, IEnumerable1 aggregates, IEnumerable1 group)
at Kendo.DynamicLinqCore.KendoAsyncExtensions.ToDataSourceResultAsync[T](IQueryable1 queryable, DataSourceRequest request) at MC.EntityFramework.DefaultImpl.Repository.AsyncRepository1.OnQueryScalarAsync[T](Task1 queryable, CancellationToken ct) at MC.Interfaces.Repository.BaseAsyncRepository1.QueryScalarAsync[T](Expression1 expression, IUserContext userContext, CancellationToken ct) at MC.AspNetCore.Controllers.CrudController1.PostGrid(DataSourceRequest request, CancellationToken ct)
at lambda_method(Closure , Object )
at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.AwaitableObjectResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
--- End of stack trace from previous location where exception was thrown ---
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|19_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Logged|17_1(ResourceInvoker invoker)
at Microsoft.AspNetCore.Routing.EndpointMiddleware.g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
at Microsoft.AspNetCore.Builder.Extensions.MapWhenMiddleware.Invoke(HttpContext context)
at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

`

[linmasaki]

@luizfbicalho @AllanVini47

Please upgrade the package to version v3.1.0. I also add NUnit test cases for you to check(See FilterTest.cs)!

[luizfbicalho]

Thanks @linmasaki I'll try it