Add initial device status service

DeviceStatus/Service/MessageHandler.cs

@@ -0,0 +1,76 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Microsoft.AspNetCore.SignalR.Client;
+using MQTTnet;
+using MQTTnet.Server;
+
+namespace Service;
+
+public class MessageHandler : IHostedService
+{
+    private MqttServer? _mqttServer;
+    private HubConnection? _hubConnection;
+
+    private readonly IConfiguration _configuration;
+    private readonly DeviceRepository _deviceRepository;
+
+    public MessageHandler(IConfiguration configuration, DeviceRepository deviceRepository)
+    {
+        _configuration = configuration;
+        _deviceRepository = deviceRepository;
+    }
+
+    public async Task StartAsync(CancellationToken cancellationToken)
+    {
+        if (!string.IsNullOrEmpty(_configuration["Hub:DeviceStatus"]))
+            _hubConnection = new HubConnectionBuilder().WithUrl(_configuration["Hub:DeviceStatus"]).Build();
+
+        var mqttFactory = new MqttFactory();
+
+        var mqttServerOptions = new MqttServerOptionsBuilder().WithDefaultEndpoint().Build();
+
+        _mqttServer = mqttFactory.CreateMqttServer(mqttServerOptions);
+        _mqttServer.InterceptingPublishAsync += OnInterceptingPublishAsync;
+
+        await _mqttServer.StartAsync();
+    }
+
+    private async Task OnInterceptingPublishAsync(InterceptingPublishEventArgs arg)
+    {
+        _deviceRepository.HandleDeviceMessage(arg.ApplicationMessage.Topic, arg.ApplicationMessage.ConvertPayloadToString());
+
+        Console.WriteLine(arg.ApplicationMessage.Topic);
+        Console.WriteLine(arg.ApplicationMessage.ConvertPayloadToString());
+
+        if (_hubConnection == null)
+            return;
+
+        try
+        {
+            if (_hubConnection.State == HubConnectionState.Disconnected)
+                _hubConnection.StartAsync().Wait();
+
+            var json = JsonSerializer.Serialize(_deviceRepository[arg.ApplicationMessage.Topic]);
+
+            await _hubConnection.InvokeAsync("SendLatestStatus", json);
+        }
+        catch (Exception exception)
+        {
+            WriteLog($"Hub exception: {exception}");
+        }
+    }
+
+    public async Task StopAsync(CancellationToken cancellationToken)
+    {
+        if (_hubConnection != null)
+            await _hubConnection.StopAsync(cancellationToken);
+
+        if (_mqttServer != null)
+            await _mqttServer.StopAsync();
+    }
+
+    private static void WriteLog(string message)
+    {
+        Console.WriteLine(message);
+    }
+}