CreateRef and DeleteRef Issue

[Diraekt]

I'm using Version 4.0.0-preview8.19405.7 which works great, thanks 👍
Yesterday I updated to Version 4.0.0 and running into the following issue (see bellow please).

Setup:
All Controllers inherit from a BaseController. The BaseController got the following definition which makes problem in 4.0.0.

       [AcceptVerbs("POST", "PUT")]
        public IActionResult CreateRef([FromODataUri] int key, [FromODataUri] string navigationProperty, [FromBody] Uri link)
        {
        }

public IActionResult DeleteRef([FromODataUri] int key, [FromODataUri]string navigationProperty, [FromBody] Uri link)
        {
           
        }

app.UseMvc(b =>
                     {
                         b.MapVersionedODataRoutes("ODataRoute", "odata/v{v:apiVersion}", GetPublicModels(modelBuilder), ConfigureAction);
                    });

In Version 4.0.0-preview8.19405.7 the recognized Path-Template is:
EntityName/{key}
where the recognized Path-Template in Version 4.0.0 is:
EntityName/{key}/{navigationProperty}/$ref

(Value from: ActionParameterContext ctor - odataPathTemplate variable)

Because of this, in the method TryGetNextSegmentText from the Odata.Core Lib, we have now 3 Segments. The last one is {navigationProperty} (PathTemplateSegment) with TargetKind Nothing, so the exception will throw.

Exception on AppStart:

ODataUnrecognizedPathException: The request URI is not valid. The segment '{navigationProperty}' must be the last segment in the URI because it is one of the following: $ref, $batch, $count, $value, $metadata, a named media resource, an action, a noncomposable function, an action import, a noncomposable function import, an operation with void return type, or an operation import with void return type. Microsoft.OData.UriParser.ODataPathParser.ThrowIfMustBeLeafSegment(ODataPathSegment previous) Microsoft.OData.UriParser.ODataPathParser.TryGetNextSegmentText(bool previousSegmentWasEscapeMarker, out string segmentText) Microsoft.OData.UriParser.ODataPathParser.ParsePath(ICollection<string> segments) Microsoft.OData.UriParser.ODataPathFactory.BindPath(ICollection<string> segments, ODataUriParserConfiguration configuration) Microsoft.OData.UriParser.ODataUriParser.ParsePathImplementation() Microsoft.OData.UriParser.ODataUriParser.Initialize() Microsoft.AspNet.OData.Routing.DefaultODataPathHandler.Parse(string serviceRoot, string odataPath, IServiceProvider requestContainer, bool template) Microsoft.AspNet.OData.Routing.DefaultODataPathHandler.ParseTemplate(string odataPathTemplate, IServiceProvider requestContainer) Microsoft.AspNet.OData.Routing.ActionParameterContext..ctor(ODataRouteBuilder routeBuilder, ODataRouteBuilderContext routeContext) Microsoft.AspNet.OData.Routing.ODataRouteBindingInfoConvention.UpdateBindingInfo(ControllerActionDescriptor action, ODataRouteMapping mapping, ICollection<ODataAttributeRouteInfo> routeInfos) Microsoft.AspNet.OData.Routing.ODataRouteBindingInfoConvention.Apply(ActionDescriptorProviderContext context, ControllerActionDescriptor action) Microsoft.AspNetCore.Mvc.ODataActionDescriptorProvider.OnProvidersExecuted(ActionDescriptorProviderContext context) Microsoft.AspNetCore.Mvc.Infrastructure.DefaultActionDescriptorCollectionProvider.UpdateCollection() Microsoft.Extensions.Primitives.ChangeToken+<>c.<OnChange>b__0_0(Action callback) Microsoft.Extensions.Primitives.ChangeToken+ChangeTokenRegistration<TState>.OnChangeTokenFired() Microsoft.Extensions.Primitives.ChangeToken+ChangeTokenRegistration<TState>+<>c.<RegisterChangeTokenCallback>b__7_0(object s) Microsoft.AspNetCore.Mvc.ODataActionDescriptorChangeProvider+ChangeToken.Callback() Microsoft.AspNetCore.Mvc.ODataActionDescriptorChangeProvider.NotifyChanged() Microsoft.AspNet.OData.Extensions.IRouteBuilderExtensions.MapVersionedODataRoutes(IRouteBuilder builder, string routeName, string routePrefix, IEnumerable<IEdmModel> models, Action<IContainerBuilder> configureAction, Action<ODataConventionConfigurationContext> configureRoutingConventions) Microsoft.AspNet.OData.Extensions.IRouteBuilderExtensions.MapVersionedODataRoutes(IRouteBuilder builder, string routeName, string routePrefix, IEnumerable<IEdmModel> models, Action<IContainerBuilder> configureAction) OrphyApi.Startup+<>c__DisplayClass28_0.<Configure>b__0(IRouteBuilder b) in Startup.cs + b.MapVersionedODataRoutes("ODataRoute", "odata/v{v:apiVersion}", GetPublicModels(modelBuilder), ConfigureAction); Microsoft.AspNetCore.Builder.MvcApplicationBuilderExtensions.UseMvc(IApplicationBuilder app, Action<IRouteBuilder> configureRoutes) OrphyApi.Startup.Configure(IApplicationBuilder app, IHostingEnvironment env, VersionedODataModelBuilder modelBuilder, IApiVersionDescriptionProvider provider) in Startup.cs + app.UseMvc(b => Microsoft.AspNetCore.Hosting.ConventionBasedStartup.Configure(IApplicationBuilder app) Microsoft.AspNetCore.Mvc.Internal.MiddlewareFilterBuilderStartupFilter+<>c__DisplayClass0_0.<Configure>g__MiddlewareFilterBuilder|0(IApplicationBuilder builder) Microsoft.Extensions.DependencyInjection.AutoRegisterMiddleware+<>c__DisplayClass4_0.<Configure>b__0(IApplicationBuilder app) Microsoft.AspNetCore.Server.IISIntegration.IISSetupFilter+<>c__DisplayClass4_0.<Configure>b__0(IApplicationBuilder app) Microsoft.AspNetCore.HostFilteringStartupFilter+<>c__DisplayClass0_0.<Configure>b__0(IApplicationBuilder app) Microsoft.AspNetCore.Hosting.Internal.AutoRequestServicesStartupFilter+<>c__DisplayClass0_0.<Configure>b__0(IApplicationBuilder builder) Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication().

How we can fix it ?

[commonsensesoftware]

Unfortunately, this is limitation in the API Versioning route building infrastructure. I knew it was there, but I wasn't sure anyone would actually hit it. This issue wasn't hit in earlier iterations because building routes for $ref wasn't supported. The issue is that OData allows for a loosey-goosey mapping. You'd think you'd be able to build the OData route template with a navigation route parameter, but it doesn't work as you can see (or I'm doing it wrong). Unless there is some way to build the template with a placeholder, the only other option I know is to fan out the template for every known navigation property. That should be possible by examining the EDM. This is bug in the sense that it doesn't work as you'd expect, but it's more of an enhancement to improve the existing behavior.

In the meantime, you have a couple of options. You can use attribute routing, which will bypass the internal route building process because you've already provided the template. I'm not sure exactly what that looks like for this scenario. If I knew what that looked like, then I should be able to generate the same template by convention.

Since you're using convention-based routing, the second option is to provide methods that complete the template. OData maps this using magic method names as a convention. For example CreateRefTo{Entity} and DeleteRefFrom{Entity}. You can map these public action methods to a single private, non-action method to achieve a behavior similar how you have things now. For example:

// from the samples, where the entity set is Products
// PUT ~/products/supplier/$ref
[HttpPut]
public IActionResult CreateRefToSupplier(
  [FromODataUri] int key,
  [FromODataUri] string navigationProperty,
  [FromBody] Uri link ) => CreateRef(key, navigationProperty, link);

// DELETE ~/products/supplier/$ref
[HttpDelete]
public IActionResult DeleteRefToSupplier(
  [FromODataUri] int key,
  [FromODataUri] string navigationProperty ) => DeleteRef(key, navigationProperty);

private IActionResult CreateRef(int key, string navigationProperty, Uri link ) => NoContent();
private IActionResult DeleteRef(int key, string navigationProperty ) => NoContent();

It's not ideal, but that should unblock you. Making this work the way it ought to will likely take quite a bit more investigation and I didn't want to hold up the entire 4.0 release for this one issue that has a workaround. If anyone else knows of a way OData will allow a route parameter in the template (and what it's key must be), that would be the simplest, fastest solution.

[commonsensesoftware]

This is now resolved in 5.0.0-RC.1. The official release will likely occur after 2 weeks of burn-in. The setup has been added in the test suite and samples. Thanks.