NoSignalR.cs

using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using CloudSoft.MessageBus.Client;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.DependencyInjection;
using Newtonsoft.Json;

namespace Gidora.Web.API.Hubs
{
    //TODO(PPavlov): Needs more work
    public interface IClient
    {
        void ReceivePreviewUrl(string previewUrl);
    }

    public class PreviewHub : Hub
    {
        private readonly IHttpClientFactory _httpClientFactory;
        private readonly IConfiguration _configuration;
        private readonly ILogger<PreviewHub> _logger;

        public PreviewHub(IServiceProvider serviceProvider)
            :base(serviceProvider)
        {
            _httpClientFactory = _serviceProvider.GetService<IHttpClientFactory>();
            _configuration = _serviceProvider.GetService<IConfiguration>();
            _logger = _serviceProvider.GetService<ILogger<PreviewHub>>();
        }

        public override void Connected()
        {
            Client.Instance.Subscribe<string>(
                this.Context.Id.ToString(),
                (previewUrl) => this.Server.Send(Context.Id, JsonConvert.SerializeObject(new WebSocketMessage()
                {
                    Method = nameof(IClient.ReceivePreviewUrl),
                    Parameters = new[] { previewUrl }
                })));
        }

        public override void Disconnected()
        {
            Client.Instance.Unsubscribe(this.Context.Id.ToString());
        }

        public async Task PushMailAsync(string body)
        {
            var subject = SubjectHelper.GenerateSubject();
            var connectionId = Context.Id;

            using (var httpClient = _httpClientFactory.CreateClient())
            {
                var content = JsonConvert.SerializeObject(new { body, subject, connectionId });

                var response = await httpClient.PostAsync($"{_configuration["Services:Gidora.Email.Client"]}/api/email/send",
                    new StringContent(body, Encoding.UTF8, "application/json"));

                if (!response.IsSuccessStatusCode)
                {
                    _logger.LogError("Email service invalid response, {statusCode}", response.StatusCode);
                }
            }
        }
    }
}