Implement R008: Add comprehensive server logging with Serilog

- Added Serilog.AspNetCore and Serilog.Sinks.File packages
- Configured daily rotating log files with 14-day retention
- Added structured logging to all server endpoints
- Log file path: logs/lnac-server-YYYYMMDD.log
- Added request logging middleware
- Logs include: client connections, messages sent/received, file operations
- Added proper exception handling with fatal error logging
- Updated .gitignore to exclude data directory

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: stho32

Source/LocalNetAppChat/.gitignore

@@ -31,6 +31,7 @@ bld/
 [Oo]bj/
 [Ll]og/
 [Ll]ogs/
+data/
 
 # Visual Studio 2015/2017 cache/options directory
 .vs/

Source/LocalNetAppChat/LocalNetAppChat.Server.Domain/Messaging/MessagingServiceProvider.cs

@@ -40,7 +40,7 @@ public Result<string> SendMessage(string key, LnacMessage message)
         var receivedMessage = _messageProcessors.Process(message.ToReceivedMessage()); 
         _messageList.Add(receivedMessage);
 
-        Console.WriteLine($"- [{DateTime.Now:yyyy-MM-dd HH:mm:ss}] queue status {_messageList.GetStatus()}");
+        Console.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss}] [INF] Queue status: {_messageList.GetStatus()}");
 
         return Result<string>.Success("Ok");
     }

Source/LocalNetAppChat/LocalNetAppChat.Server/LocalNetAppChat.Server.csproj

@@ -12,6 +12,11 @@
       <ProjectReference Include="..\LocalNetAppChat.Server.Domain\LocalNetAppChat.Server.Domain.csproj" />
     </ItemGroup>
 
+    <ItemGroup>
+      <PackageReference Include="Serilog.AspNetCore" Version="8.0.0" />
+      <PackageReference Include="Serilog.Sinks.File" Version="5.0.0" />
+    </ItemGroup>
+
     <ItemGroup>
       <Reference Include="System.ServiceModel.Primitives">
         <HintPath>..\..\..\..\..\Users\Entwickler\.nuget\packages\system.servicemodel.primitives\4.10.0\ref\net6.0\System.ServiceModel.Primitives.dll</HintPath>

Source/LocalNetAppChat/LocalNetAppChat.Server/Program.cs

@@ -6,6 +6,8 @@
 using LocalNetAppChat.Server.Domain.Messaging.MessageProcessing;
 using LocalNetAppChat.Server.Domain.Security;
 using LocalNetAppChat.Server.Domain.StoringFiles;
+using Serilog;
+using Serilog.Events;
 
 var parser = new Parser(
     new ICommandLineOption[] {
@@ -39,112 +41,186 @@
         $"\n\n [Usage]\n\n" +
         $"\n{string.Join("\n", commandsWithDescription)}");
 
-    Console.WriteLine("\n\nExamples:\r\n\r\n  – Start the server with the default settings\r\n    $ LocalNetAppChat.Server\r\n  - Start the server in HTTPS mode\r\n    $ LocalNetAppChat.Server --https\r\n  - Start the server with different ip and port and custom key\r\n    $ LocalNetAppChat.Server --listenOn \"54.15.12.1\" --port \"54822\" --https --key \"HeythereGithubExample\"");
+    Console.WriteLine("\n\nExamples:\r\n\r\n  � Start the server with the default settings\r\n    $ LocalNetAppChat.Server\r\n  - Start the server in HTTPS mode\r\n    $ LocalNetAppChat.Server --https\r\n  - Start the server with different ip and port and custom key\r\n    $ LocalNetAppChat.Server --listenOn \"54.15.12.1\" --port \"54822\" --https --key \"HeythereGithubExample\"");
 
     return;
 }
 
-var serverKey = parser.TryGetOptionWithValue<string>("--key");
-var accessControl = new KeyBasedAccessControl(serverKey??string.Empty);
+// Configure Serilog
+var logsDirectory = Path.Combine(Directory.GetCurrentDirectory(), "logs");
+Directory.CreateDirectory(logsDirectory);
+
+Log.Logger = new LoggerConfiguration()
+    .MinimumLevel.Information()
+    .MinimumLevel.Override("Microsoft.AspNetCore", LogEventLevel.Warning)
+    .Enrich.FromLogContext()
+    .WriteTo.Console(outputTemplate: "[{Timestamp:yyyy-MM-dd HH:mm:ss}] [{Level:u3}] {Message:lj}{NewLine}{Exception}")
+    .WriteTo.File(
+        Path.Combine(logsDirectory, "lnac-server-.log"),
+        rollingInterval: RollingInterval.Day,
+        retainedFileCountLimit: 14,
+        outputTemplate: "[{Timestamp:yyyy-MM-dd HH:mm:ss}] [{Level:u3}] {SourceContext} {Message:lj}{NewLine}{Exception}")
+    .CreateLogger();
+
+try
+{
+    Log.Information("Starting LocalNetAppChat Server");
+
+    var serverKey = parser.TryGetOptionWithValue<string>("--key");
+    var accessControl = new KeyBasedAccessControl(serverKey??string.Empty);
+
+    var messagingServiceProvider = new MessagingServiceProvider(
+        accessControl,
+        MessageProcessorFactory.Get(
+            new ThreadSafeCounter(),
+            new DateTimeProvider())
+        );
 
-var messagingServiceProvider = new MessagingServiceProvider(
-    accessControl,
-    MessageProcessorFactory.Get(
-        new ThreadSafeCounter(),
-        new DateTimeProvider())
-    );
+    var storageServiceProvider = new StorageServiceProvider(
+        accessControl,
+        Path.Combine(Directory.GetCurrentDirectory(), "data"));
 
-var storageServiceProvider = new StorageServiceProvider(
-    accessControl,
-    Path.Combine(Directory.GetCurrentDirectory(), "data"));
+    var hostingUrl = HostingUrlGenerator.GenerateUrl(
+        parser.GetOptionWithValue<string>("--listenOn") ?? "",
+        parser.GetOptionWithValue<int>("--port"),
+        parser.GetBoolOption("--https"));
 
-var hostingUrl = HostingUrlGenerator.GenerateUrl(
-    parser.GetOptionWithValue<string>("--listenOn") ?? "",
-    parser.GetOptionWithValue<int>("--port"),
-    parser.GetBoolOption("--https"));
+    Log.Information("Server configured to listen on {HostingUrl} with key authentication", hostingUrl);
 
-var builder = WebApplication.CreateBuilder(new[] { "--urls", hostingUrl });
+    var builder = WebApplication.CreateBuilder(new[] { "--urls", hostingUrl });
+    builder.Host.UseSerilog();
 var app = builder.Build();
 
-app.MapGet("/", () => "LocalNetAppChat Server!");
+    // Add Serilog request logging
+    app.UseSerilogRequestLogging(options =>
+    {
+        options.MessageTemplate = "HTTP {RequestMethod} {RequestPath} responded {StatusCode} in {Elapsed:0.0000} ms";
+    });
+
+    app.MapGet("/", () => "LocalNetAppChat Server!");
 
 app.MapGet("/receive", (string key, string clientName) =>
 {
+    Log.Debug("Client {ClientName} requesting messages", clientName);
     var result = messagingServiceProvider.GetMessages(key, clientName);
 
     if (!result.IsSuccess)
     {
+        Log.Warning("Failed to get messages for client {ClientName}: {Error}", clientName, result.Error);
         return result.Error;        
     }
 
+    Log.Information("Delivered {MessageCount} messages to client {ClientName}", result.Value.Length, clientName);
     return JsonSerializer.Serialize(result.Value);
 });
 
 app.MapPost("/send", (string key, LnacMessage message) =>
 {
+    Log.Information("Received message from {ClientName}: {MessageText}", message.Name, message.Text);
     var result = messagingServiceProvider.SendMessage(key, message);
 
     if (!result.IsSuccess)
     {
+        Log.Warning("Failed to send message from {ClientName}: {Error}", message.Name, result.Error);
         return result.Error;
     }
 
+    Log.Debug("Message from {ClientName} successfully queued", message.Name);
     return result.Value;
 });
 
 app.MapPost("/upload", async (HttpRequest request, string key) =>
 {
     if (!request.HasFormContentType)
+    {
+        Log.Warning("Upload request received without form content type");
         return Results.BadRequest();
+    }
 
     var form = await request.ReadFormAsync();
 
     if (form.Files.Any() == false)
+    {
+        Log.Warning("Upload request received without files");
         return Results.BadRequest("There are no files");
+    }
 
     var file = form.Files.FirstOrDefault();
 
     if (file is null || file.Length == 0)
+    {
+        Log.Warning("Upload request received with empty file");
         return Results.BadRequest("File cannot be empty");
+    }
 
+    Log.Information("Uploading file {FileName} ({FileSize} bytes)", file.FileName, file.Length);
     var result = await storageServiceProvider.Upload(key,
         file.FileName, file.OpenReadStream());
 
     if (!result.IsSuccess)
+    {
+        Log.Error("Failed to upload file {FileName}: {Error}", file.FileName, result.Error);
         return Results.BadRequest(result.Error);
+    }
 
+    Log.Information("Successfully uploaded file {FileName}", file.FileName);
     return Results.Content(result.Value);
 });
 
 
 app.MapGet("/listallfiles", (string key) =>
 {
+    Log.Debug("Listing all files request received");
     var result = storageServiceProvider.GetFiles(key);
 
     if (!result.IsSuccess)
+    {
+        Log.Warning("Failed to list files: {Error}", result.Error);
         return Results.BadRequest(result.Error);
+    }
 
+    Log.Information("Listed {FileCount} files", result.Value.Length);
     return Results.Json(result.Value);
 });
 
 app.MapGet("/download", async (HttpRequest _, string key, string filename) =>
 {
+    Log.Information("Download request for file {FileName}", filename);
     var result = await storageServiceProvider.Download(key, filename);
 
     if (!result.IsSuccess)
+    {
+        Log.Warning("Failed to download file {FileName}: {Error}", filename, result.Error);
         return Results.BadRequest(result.Error);
+    }
 
+    Log.Information("Successfully downloaded file {FileName}", filename);
     return Results.File(result.Value, fileDownloadName: filename);
 });
 
 app.MapPost("/deletefile", (HttpRequest _, string filename, string key) =>
 {
+    Log.Information("Delete request for file {FileName}", filename);
     var result = storageServiceProvider.Delete(key, filename);
 
     if (!result.IsSuccess)
+    {
+        Log.Warning("Failed to delete file {FileName}: {Error}", filename, result.Error);
         return Results.BadRequest(result.Error);
+    }
 
+    Log.Information("Successfully deleted file {FileName}", filename);
     return Results.Content(result.Value);
 });
 
-app.Run();
+    Log.Information("Server started successfully");
+    app.Run();
+}
+catch (Exception ex)
+{
+    Log.Fatal(ex, "Server terminated unexpectedly");
+}
+finally
+{
+    Log.CloseAndFlush();
+}