Case mismatch on select/expand results in non-OData route

[mitchdowd]

Adding OData query handling to an existing controller results in non-camelCase resulting property names when $select or $expand is used. Ideally the results should be consistent.

Assemblies affected

Currently using Microsoft.AspNetCore.OData v7.0.0

Reproduce steps

Have an existing controller with a non-OData route.

    [Route("api/values")]
    public class ValuesController : ODataController
    {
        private ValuesRepository _repo;

        public ValuesController(ValuesRepository repo)
        {
            _repo = repo;
        }

        [HttpGet]
        [EnableQuery]
        public IQueryable<Value> Get()
        {
            return _repo.Get();
        }
    }

Configure the OData EDM route, and also enable dependency injection for the existing controller route.

    public void Configure(IApplicationBuilder app)
    {
        app.UseMvc(routeBuilder =>
        {
            var modelBuilder = new ODataConventionModelBuilder();

            // EDM builder for the /odata route.
            modelBuilder.EnableLowerCamelCase()
                .EntitySet<Value>("Values")
                    .EntityType
                    .Select();

            routeBuilder.MapODataServiceRoute("ODataRoute", "odata", modelBuilder.GetEdmModel());

            // Dependency injection for the /api route.
            routeBuilder
                .Select()
                .EnableDependencyInjection();
        });
    }

Access the resulting API call from:

• http://localhost:8001/api/values (gives correct camelCasing)
• http://localhost:8001/odata/values?$select=id (gives correct camelCasing)
• http://localhost:8001/api/values?$select=id (gives incorrect PascalCasing)

Expected result

I would expect consistent case-handling for both /api and /odata routes. This would allow OData query parameters to be handled on existing APIs without breaking the resulting response packet.

Actual result

While /odata/values?$select=id gives a correct response like [ { "id": 1 } ], using the /api route will give [ { "Id": 1 } ].

Additional detail

Example standalone ASP.NET Core project: ODataCamelCase.zip

[mitchdowd]

Closing. Explicitly setting JSON SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver() fixes it up.

[ayanmitra2021]

Any ideas on how the same thing can be achieved on a NestJS based Node api

[yoHasse]

This helped me which i found at:
GitHub OData: camel_case_scenarios.md

This is what resolved it for me:

builder.Services.AddControllers()
    .AddJsonOptions(options =>
    {
        options.JsonSerializerOptions.DictionaryKeyPolicy = JsonNamingPolicy.CamelCase;
        options.JsonSerializerOptions.PropertyNamingPolicy = JsonNamingPolicy.CamelCase;
    });