Refit: Allow: Aggregated interfaces

[ahmedalejo]

Currently, if an API interface A(HasRefitHttpMethodAttribute) is an aggregation of other interfaces(HasRefitHttpMethodAttribute) then the generated stub for A doesn´t implement the aggregated interfaces;

using Refit
...
interface InterfaceA : InterfaceB
{
    [Get("/ping")]
    Task Ping(); 
}

interface InterfaceB
{
    [Get("/ping")]
    Task Pong(); 
}

The generated stub look like this, and doesn´t obviously compile

using Refit
...
class AutoGeneratedA : InterfaceA
{
    ...
    public Task Ping() { ... }
}

class AutoGeneratedB : InterfaceB
{
    ...
    public Task Pong() { ... }
}

This should/could have been the following

using Refit
...
class AutoGeneratedA  : AutoGeneratedB, InterfaceA
{
    ...
    public Task Ping() { ... }
}

class AutoGeneratedB : InterfaceB
{
    ...
    public Task Pong() { ... }
}

I´m trying to seggregate the interface to better know what client a particular ViewModel(of my MVVM) uses or is supposed to use, i use a IoC container to inject specific implementations.

The registration uses reflection:

using System;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Reflection;
using Refit;

namespace Service.Clients
{
    using Core.Common;
    using IoC;

    public class RestServicesWrapper
    {
        static RestServicesWrapper()
        {
            RestServiceType = typeof(RestService);

            var parameterTypes = new Type[] { typeof(HttpClient) };
            RestServiceFactory = RestServiceType.GetRuntimeMethod("For", parameterTypes);
            WebApiClientsAssembly = typeof(RestServicesWrapper).GetTypeInfo().Assembly; ;
        }

        private static MethodInfo RestServiceFactory { get; set; }
        private static Type RestServiceType { get; set; }
        private static Assembly WebApiClientsAssembly { get; set; }

        public static object For(Type serviceContractType, HttpClient httpClient)
        {
            return RestServiceFactory
                .MakeGenericMethod(serviceContractType)
                .Invoke(RestServiceType, new object[] { httpClient });
        }

        public static void RegisterServices()
        {
            var httpClient = new HttpClient();

            var services =
                from service in WebApiClientsAssembly.ExportedTypes
                let type = service.GetTypeInfo()
                where type.GetCustomAttributes<WebApiContractAttribute>().Any() // A custom marker attribute
                select service;

            var container = Container.Default;

            foreach (var service in services)
                container.Register(service, () => For(service, httpClient));
        }
    }
}

[ahmedalejo]

Hi any word on this. at least a "NO WAY"(with why) would be apreciated! @paulcbetts :)
Just for the love your "reactive endeavours"

[aloisdeniel]

For me it is an important missing feature too!

Your suggestion could not be used because multiple classes inheritance isn't supported by C#.

Imagine you have :

interface A : B, C
{
    [Get("/ping")]
    Task Ping(); 
}

interface B
{
    [Get("/pong")]
    Task Pong(); 
}

interface C
{
    [Get("/pang")]
    Task Pang(); 
}

Then, this is not valid :

using Refit
...
class A : AutoGeneratedB, AutoGeneratedC, A // <- Not valid !
{
    ...
    public Task Ping() { ... }
}

class AutoGeneratedB : B
{
    ...
    public Task Pong() { ... }
}

class AutoGeneratedC : C
{
    ...
    public Task Pang() { ... }
}

But you could do that at generation, all methods from inherited interfaces could be reflected and regenerated each time by all registered child interfaces.

[ahmedalejo]

but this is valid

using Refit
...
class A : AutoGeneratedB, A
{
    ...
    public Task Ping() { ... }
}

class AutoGeneratedB : AutoGeneratedC, B
{
    ...
    public Task Pong() { ... }
}

class AutoGeneratedC : C
{
    ...
    public Task Pang() { ... }
}

//And so is this

using Refit
...
class AutoGeneratedABC : A, B, C
{
    ...
    Task A.Ping() { ... }
    ...
    Task B.Pong() { ... }
    ...
    Task C.Pang() { ... }
}

[aloisdeniel]

Yes, I was thinking about this. I'll try to see if I could do a PR for this, maybe @paulcbetts hasn't much time at the moment. :)

[iss0]

Any progress here? This feature would be really a great enhancement. Imagine the possibilities!

[Sergio0694]

This too was just done in #633 - so this can be closed as well 😊