Kavita/API/Extensions/ServiceCollectionExtensions.cs

using System;
using API.Interfaces.Services;
using API.Services.Clients;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

namespace API.Extensions
{
    public static class ServiceCollectionExtensions
    {
        public static IServiceCollection AddStartupTask<T>(this IServiceCollection services)
            where T : class, IStartupTask
            => services.AddTransient<IStartupTask, T>();

        public static IServiceCollection AddStatsClient(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddHttpClient<StatsApiClient>(client =>
            {
                client.DefaultRequestHeaders.Add("api-key", "MsnvA2DfQqxSK5jh");
            });

            return services;
        }
    }
}