manager-service/ManagerService/Extensions/MqttClientService.cs

using Manager.Interfaces.Models;
using Manager.Services;
using MQTTnet;
using MQTTnet.Client;
using MQTTnet.Client.Connecting;
using MQTTnet.Client.Disconnecting;
using MQTTnet.Client.Options;
using MQTTnet.Protocol;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace Mqtt.Client.AspNetCore.Services
{
    public class MqttClientService : IMqttClientService
    {
        private static IMqttClient mqttClient;
        private IMqttClientOptions options;
        static DeviceDatabaseService _deviceDatabaseService;
        static ConfigurationDatabaseService _configurationDatabaseService;

        public static string lastTopic; 
        public static long lastTimeTopic;

        public MqttClientService(IMqttClientOptions options)
        {
            var server = "localhost";
#if DEBUG
            server = "192.168.31.96";
#endif
            this.options = options;
            this.options = new MqttClientOptionsBuilder()
                    .WithClientId(options.ClientId) 
                    .WithTcpServer(server)
                    .WithCredentials(options.Credentials.Username, options.Credentials.Password)
                    .WithCleanSession()
                    .Build();
            mqttClient = new MqttFactory().CreateMqttClient();
            ConfigureMqttClient();
        }

        private void ConfigureMqttClient()
        {
            mqttClient.ConnectedHandler = this;
            mqttClient.DisconnectedHandler = this;
            mqttClient.ApplicationMessageReceivedHandler = this;
        }

        public Task HandleApplicationMessageReceivedAsync(MqttApplicationMessageReceivedEventArgs e)
        {
            var payload = "";
            if (e.ApplicationMessage.Payload != null)
            {
                payload = Encoding.UTF8.GetString(e.ApplicationMessage.Payload);
            }

            var topic = e.ApplicationMessage.Topic;

            var currentTime = DateTimeOffset.Now.ToUnixTimeMilliseconds();

            try 
            {
                var deserialized = JsonConvert.DeserializeObject<Dictionary<string, object>>(payload);

                switch (topic.Split("/")[0]) 
                {
                    case "player":
                        var test = topic.Split("/")[1]; // Get device id

                        if (topic == "player/status") {
                            var deviceId = (string)deserialized["deviceId"];
                            var connectedStatus = (bool)deserialized["connected"];

                            Device device = _deviceDatabaseService.GetById(deviceId);

                            if (device != null)
                            {
                                device.Connected = connectedStatus;

                                _deviceDatabaseService.Update(device.Id, device);
                            }
                        }
                        break;
                }

            } catch (Exception ex) 
            { 

            }

            return null;
        }

        public async Task HandleConnectedAsync(MqttClientConnectedEventArgs eventArgs)
        {
            System.Console.WriteLine("connected");
            await mqttClient.SubscribeAsync("#");
        }

        public async Task HandleDisconnectedAsync(MqttClientDisconnectedEventArgs eventArgs)
        {
            if (!mqttClient.IsConnected)
            {
                await mqttClient.ReconnectAsync();
            }
        }

        public async Task StartAsync(CancellationToken cancellationToken)
        {
            await mqttClient.ConnectAsync(options);
            if (!mqttClient.IsConnected)
            {
                await mqttClient.ReconnectAsync();
            }
        }

        public async Task StopAsync(CancellationToken cancellationToken)
        {
            if(cancellationToken.IsCancellationRequested)
            {
                var disconnectOption = new MqttClientDisconnectOptions
                {
                    ReasonCode = MqttClientDisconnectReason.NormalDisconnection,
                    ReasonString = "NormalDiconnection"
                };
                await mqttClient.DisconnectAsync(disconnectOption, cancellationToken);
            }
            await mqttClient.DisconnectAsync();
        }

        public static async Task PublishMessage(string topic, string message)
        {
            var mqttMessage = new MqttApplicationMessageBuilder()
                .WithTopic(topic)
                .WithPayload(message)
                .WithAtMostOnceQoS()
                .WithQualityOfServiceLevel(MqttQualityOfServiceLevel.AtMostOnce)
                .WithRetainFlag(false)
                .Build();

            if (mqttClient.IsConnected)
                await mqttClient.PublishAsync(mqttMessage);
        }

        public static void SetServices(DeviceDatabaseService _DeviceDatabaseService, ConfigurationDatabaseService _ConfigurationDatabaseService)
        {
            _deviceDatabaseService = _DeviceDatabaseService;
            _configurationDatabaseService = _ConfigurationDatabaseService;
        }
    }
}