Using $compute with ODataQueryOptions<T> not supported?

[blueghostuk]

Discussed in #920

^{Originally posted by blueghostuk May 15, 2023}
$compute does not seem to work when using ODataQueryOptions<T>. A simple example calculating the length of a string and selecting it.

We are using EF Core, if I just pass $compute and $select, it fails with an error like:

Microsoft.OData.ODataException: Could not find a property named '{{propertyName}}' on type '{{entityType}}'.

If I also pass a $filter, I can see the SQL being generated but then fails with:
System.InvalidOperationException: Sequence contains no matching element at System.Linq.ThrowHelper.ThrowNoMatchException() at Microsoft.AspNetCore.OData.Query.Container.JsonPropertyNameMapper.MapProperty(String propertyName) at Microsoft.AspNetCore.OData.Query.Container.NamedProperty1.ToDictionaryCore(Dictionary2 dictionary, IPropertyMapper propertyMapper, Boolean includeAutoSelected) at Microsoft.AspNetCore.OData.Query.Wrapper.SelectExpandWrapper.ToDictionary(Func3 mapperProvider)
at Microsoft.AspNetCore.OData.Query.Wrapper.SelectSomeConverter1.Write(Utf8JsonWriter writer, SelectSome1 value, JsonSerializerOptions options)`

Example project here - https://github.com/blueghostuk/odata-compute-issue

Is there anything I am doing wrong? Or is this not supported?

[xuzhg]

For Microsoft.OData.ODataException: Could not find a property named '{{propertyName}}' on type '{{entityType}}'.

==> @mikepizzo ODL still needs the structural type to be 'open' type then we can use extra/dynamic properties on it. But, OData spec doesn't have such a limitation. Do you think it's time to change ODL behavior?

For System.InvalidOperationException: Sequence contains no matching element at System.Linq.ThrowHelper.ThrowNoMatchException() at Microsoft.AspNetCore.OData.Query.Container.JsonPropertyNameMapper.MapProperty(String propertyName)

==> @xuzhg This is an issue in non-odata scenarios containing dynamic properties. It's a bug and should fix it (@1)

As a workaround, customer can customize the 'IPropertyMapper' to skip it, but there's no way for customer to cusotmize it on System.Text.Json. So, we need to fix it. ( @2 )

@blueghostuk Before the fix, here's a workaround.

1. Add 'public IDictionary<string, object> Data { get; set; }' into 'WeatherForecast' to let the model builder to build the type as open type. (This can kill the first error)

2. We'd have to switch to use OData Newtonsoft.JSON.

2.a) Update the project as:

<ItemGroup>
  <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="6.0.16" />
  <PackageReference Include="Microsoft.AspNetCore.OData" Version="8.1.2" />
  <PackageReference Include="Microsoft.AspNetCore.OData.NewtonsoftJson" Version="8.1.1" />
</ItemGroup>

a.b) Create the following class.

    public class MyPropertyMapper : IPropertyMapper
    {
        public string MapProperty(string propertyName)
        {
            return propertyName;
        }
    }

2.c) use the class in configuration as:

builder.Services.AddControllers() .AddOData().AddODataNewtonsoftJson((model, structuredType) =>
  {
      return new MyPropertyMapper();
  });

then it should work as:

[xuzhg]

@blueghostuk Please take a look the fix at: #928. Thanks.

[blueghostuk]

Thanks for the quick fix!