How can I get an OData-formatted response from a custom GET route with query parameters?

[dwoldo]

Hi all! 👋

I'm trying to add a new GET endpoint that accepts query parameters and returns an OData-compliant response.

✅ Expected Response

{
  "@odata.context": "...",
  "value": [{ ... }]
}

❌ Actual Response

[{ ... }]

---

🧾 Controller Setup

[Route("v1/endpoints")]
public class EndpointsController : ODataController
{
    [EnableQuery]
    [HttpGet]
    public async Task<IEnumerable<Endpoint>> GetAll()
    {
        return endpointsIQueryable;
    }
    // Request: GET domain.com/v1/endpoints
    // Response: { "value": [{...}] } ✅ OData wrapped
  

    [EnableQuery]
    [HttpGet("withStaticFilters")]
    public async Task<IEnumerable<Endpoint>> GetAllWithStaticFilters()
    {
        return endpointsIQueryable;
    }
    // Request: GET domain.com/v1/endpoints/withStaticFilters
    // Response: [{...}] ❌ Not wrapped in "value" or "@odata.context"
}

---

⚙️ Program/Startup Configuration

services.AddOData((opt, sp) =>
{
    opt.Select().Filter().Count().Expand().SetMaxTop(1000).OrderBy();
    opt.TimeZone = TimeZoneInfo.Utc;

    var model = new ODataConventionModelBuilder();
    model.EnableLowerCamelCase();

    opt.AddRouteComponents("v1", GetEdmModel());
});

IEdmModel GetEdmModel()
{
    var builder = new ODataConventionModelBuilder();
    var endpoint = builder.EntitySet<Endpoint>("endpoints");
    endpoint.EntityType.HasKey(x => x.Id);

    return builder.GetEdmModel();
}

---

❓ Question

How can I modify the withStaticFilters endpoint so it returns a proper OData response (with @odata.context and value)—just like the default GET route?

Is there a limitation with custom routes like v1/endpoints/withStaticFilters, or do I need to configure something extra to make it OData-compliant?

Any guidance is appreciated!

[habbes]

Hello @dwoldo, the GetAllWithStaticFilters() endpoint has not corresponding mapping in your OData schema. Since OData doesn't know about it, it doesn't handle it. If you want OData to handle it, you can add it to your OData schema, or you can register an ODataFeature in the controller so that the ODataOutputFormatter can take over the serialization.

The first approach is probably the easiest and most standard way. You could map the endpoint to your schema as a bound function. To learn more about creating endpoints for bound functions, check out the docs: https://learn.microsoft.com/en-us/odata/webapi-8/fundamentals/actions-functions

So in this case you could register withStaticFilters as a function bound to a collection of Endpoint entities:

var builder = new ODataConventionModelBuilder();
var endpoint = builder.EntitySet<Endpoint>("endpoints");
endpoint.EntityType.HasKey(x => x.Id);
+ builder.EntityType<Endpoint>().Collection
+      .Function("withStaticFilters")
+      .ReturnsCollectionFromEntitySet<Endpoint>("endpoints");