compelling fusillade + refit example

gistfile1.cs

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Threading.Tasks;
using EndlessCatsApi.ServiceModel;
using EndlessCatsApp.Core.Helpers;
using Fusillade;
using Refit;

namespace EndlessCatsApp.Core.Services
{
    [Headers("User-Agent: " + AppSettings.ApiClientUserAgent)]
    public interface IEndlessCatsApi
    {
        /// <remarks>
        /// - You can redefine the user-agent header on a per request basis via: [Headers("User-Agent: ELinks/0.9.3 (textmode; Linux 2.6.11 i686; 79x24)"]
        /// - You can remove the user-agent header on a per request basis via: [Headers("User-Agent")]
        /// </remarks>
        [Get("/cats")]
        Task<List<Cat>> GetMoreCats([Header("X-Auth-Token")] string apiKey);
    }

    public interface IApiService
    {
        IEndlessCatsApi Speculative { get; }
        IEndlessCatsApi UserInitiated { get; }
        IEndlessCatsApi Background { get; }
    }

    public class ApiService : IApiService
    {
        public const string ApiBaseAddress = "https://endlesscats.azurewebsites.net/api";

        public ApiService(string apiBaseAddress = null)
        {
            Func<HttpMessageHandler, IEndlessCatsApi> createClient = messageHandler =>
            {
                Ensure.ArgumentIsOfType(messageHandler, typeof(RateLimitedHttpMessageHandler), "Fusillade RateLimitedHttpMessageHandler");

                var client = new HttpClient(messageHandler)
                {
                    BaseAddress = new Uri(apiBaseAddress ?? ApiBaseAddress)
                };

                return RestService.For<IEndlessCatsApi>(client);
            };

            _background = new Lazy<IEndlessCatsApi>(() => RestService.For<IEndlessCatsApi>(ApiBaseAddress));
            _userInitiated = new Lazy<IEndlessCatsApi>(() => RestService.For<IEndlessCatsApi>(ApiBaseAddress));
            _speculative = new Lazy<IEndlessCatsApi>(() => RestService.For<IEndlessCatsApi>(ApiBaseAddress));
        }

        private readonly Lazy<IEndlessCatsApi> _background;
        private readonly Lazy<IEndlessCatsApi> _userInitiated;
        private readonly Lazy<IEndlessCatsApi> _speculative;

        public IEndlessCatsApi Background
        {
            get { return _background.Value; }
        }

        public IEndlessCatsApi UserInitiated
        {
            get { return _userInitiated.Value; }
        }

        public IEndlessCatsApi Speculative
        {
            get { return _speculative.Value; }
        }
    }
}

var apiService = Locator.Current.GetType<IAPIService>();

// use this to download items such as avatars or thumbnail photos in background.
// If request for UserInitiated comes through then a processing slot of this
// queue is stolen for UserInitiated until it completes. 
apiService.Background.GetMoreCats();        

// use this download items in response to user action, say view fullsize photo.
apiService.UserInitiated.GetMoreCats();     

// use this to speculatively prefetch items a user may do a user action on.
// for example speculatively download fullsize photos that a user may click on
// if the device is connected by Wifi. ala Chrome HTTP Prefetch. Don't forget
// to configure the NetCache.Speculative.ResetLimit(1048576 * 5/*MB*/) as appropriate.
apiService.Speculative.GetMoreCats();

For completeness sake... I had to change lines 48,49,50 to...

_background = new Lazy<ITekConfApi>(() => createClient(
    new RateLimitedHttpMessageHandler(new NativeMessageHandler(), Priority.Background)));

_userInitiated = new Lazy<ITekConfApi>(() => createClient(
    new RateLimitedHttpMessageHandler(new NativeMessageHandler(), Priority.UserInitiated)));

_speculative = new Lazy<ITekConfApi>(() => createClient(
    new RateLimitedHttpMessageHandler(new NativeMessageHandler(), Priority.Speculative)));

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