SyslogLogging

SyslogLogging

🚀 Modern, high-performance C# logging library for syslog, console, and file destinations with async support, structured logging, and Microsoft.Extensions.Logging integration.

Targeted to .NET Standard 2.0+, .NET Framework 4.6.2+, .NET 6.0+, and .NET 8.0.

✨ What's New in v2.0.9+

🔥 Major New Features

• 🌪️ Full async support with CancellationToken throughout
• 📊 Structured logging with properties, correlation IDs, and JSON serialization
• 🔌 Microsoft.Extensions.Logging integration (ILogger, DI support)
• 🏗️ Enterprise-grade thread safety with comprehensive race condition prevention
• 🎯 Integrated SyslogServer for end-to-end testing
• 🛡️ Comprehensive input validation on all public properties
• 🧪 Extensive thread safety testing (20+ specialized concurrent scenarios)

🔧 Performance & Reliability

• Thread-safe operations with proper locking mechanisms
• Immediate log delivery with direct processing
• Memory efficient with minimal overhead
• Standards compliant RFC 3164 syslog format support

🚀 Quick Start

Simple Logging

using SyslogLogging;

LoggingModule log = new LoggingModule();
await log.InfoAsync("Hello, world!");

Async with Structured Data

using SyslogLogging;

LoggingModule log = new LoggingModule("mysyslogserver", 514);

// Simple async logging
await log.ErrorAsync("Something went wrong", cancellationToken);

// Structured logging with properties
LogEntry entry = new LogEntry(Severity.Warning, "Rate limit exceeded")
    .WithProperty("RequestsPerSecond", 150)
    .WithProperty("ClientId", "user123")
    .WithCorrelationId(Request.Headers["X-Correlation-ID"]);

await log.LogEntryAsync(entry);

Fluent Structured Logging

log.BeginStructuredLog(Severity.Info, "User login")
    .WithProperty("UserId", userId)
    .WithProperty("IpAddress", ipAddress)
    .WithProperty("Timestamp", DateTime.UtcNow)
    .WithCorrelationId(correlationId)
    .WriteAsync();

🔌 Microsoft.Extensions.Logging Integration

ASP.NET Core / Generic Host

// Program.cs or Startup.cs
services.AddLogging(builder =>
{
    builder.AddSyslog("syslogserver", 514);
});

// In your controllers/services
public class MyController : ControllerBase
{
    private readonly ILogger<MyController> _logger;

    public MyController(ILogger<MyController> logger)
    {
        _logger = logger;
    }

    public IActionResult Get()
    {
        _logger.LogInformation("API called with correlation {CorrelationId}",
            HttpContext.TraceIdentifier);
        return Ok();
    }
}

Multiple Destinations

services.AddLogging(builder =>
{
    builder.AddSyslog(new List<SyslogServer>
    {
        new SyslogServer("primary-log", 514),
        new SyslogServer("backup-log", 514)
    }, enableConsole: true);
});

📊 Advanced Structured Logging

Rich Metadata

LogEntry entry = new LogEntry(Severity.Error, "Payment processing failed")
    .WithProperty("OrderId", orderId)
    .WithProperty("Amount", amount)
    .WithProperty("Currency", "USD")
    .WithProperty("PaymentProvider", "Stripe")
    .WithProperty("ErrorCode", errorCode)
    .WithCorrelationId(correlationId)
    .WithSource("PaymentService")
    .WithException(exception);

await log.LogEntryAsync(entry);

JSON Serialization

LogEntry entry = new LogEntry(Severity.Info, "User session")
    .WithProperty("SessionDuration", TimeSpan.FromMinutes(45))
    .WithProperty("PagesVisited", new[] { "/home", "/products", "/checkout" });

string json = entry.ToJson();
// Output: {"timestamp":"2023-12-01T10:30:00.000Z","severity":"Info","message":"User session","threadId":1,"properties":{"SessionDuration":"00:45:00","PagesVisited":["/home","/products","/checkout"]}}

🎯 Multiple Destinations

Syslog + Console + File

List<SyslogServer> servers = new List<SyslogServer>
{
    new SyslogServer("primary-syslog", 514),
    new SyslogServer("backup-syslog", 514)
};

LoggingModule log = new LoggingModule(servers, enableConsole: true);
log.Settings.FileLogging = FileLoggingMode.FileWithDate;  // Creates dated files
log.Settings.LogFilename = "./logs/app.log";

log.Alert("This goes to 2 syslog servers, console, AND file!");

File-Only Logging

LoggingModule log = new LoggingModule("./logs/app.log", FileLoggingMode.SingleLogFile);
await log.InfoAsync("File-only message");

Log Retention (Automatic Cleanup)

// Automatically delete log files older than 30 days
LoggingModule log = new LoggingModule("./logs/app.log", FileLoggingMode.FileWithDate, true);
LoggingSettings settings = log.Settings;
settings.LogRetentionDays = 30;  // Keep 30 days of logs (0 = disabled, default)
log.Settings = settings;         // Re-assign to start cleanup timer

// Or configure settings first
LoggingSettings settings = new LoggingSettings();
settings.LogFilename = "./logs/app.log";
settings.FileLogging = FileLoggingMode.FileWithDate;
settings.LogRetentionDays = 7;   // Keep 7 days of logs
LoggingModule log = new LoggingModule();
log.Settings = settings;

Note: Log retention only applies when using FileLoggingMode.FileWithDate. The cleanup timer runs every 60 seconds and removes files matching the pattern filename.ext.yyyyMMdd that are older than the specified retention period.

🎨 Console Colors & Formatting

Enable Colors

log.Settings.EnableColors = true;
log.Settings.Colors.Error = new ColorScheme(ConsoleColor.Red, ConsoleColor.Black);
log.Settings.Colors.Warning = new ColorScheme(ConsoleColor.Yellow, ConsoleColor.Black);

Custom Message Format with Rich Variables

// Basic format
log.Settings.HeaderFormat = "{ts} [{sev}] {host}:{thread}";

// Detailed production format
log.Settings.HeaderFormat = "{ts} {host}[{pid}] {sev} [T:{thread}] [{app}]";

// Performance monitoring format
log.Settings.HeaderFormat = "{ts} {host} CPU:{cpu} MEM:{mem}MB UP:{uptime} {sev}";

// Microservices format
log.Settings.HeaderFormat = "{ts} [{app}:{pid}] {sev} [{correlation}] [{source}]";

log.Settings.TimestampFormat = "yyyy-MM-dd HH:mm:ss.fff";
log.Settings.UseUtcTime = true;

Available Header Format Variables

Variable	Description	Example Output
{ts}	Timestamp	2024-01-15 14:30:25.123
{host}	Machine name	web-server-01
{thread}	Thread ID	12
{sev}	Severity name	Info
{level}	Severity number (0-7)	6
{pid}	Process ID	1234
{user}	Current username	john.doe
{app}	Application name	MyWebApp
{domain}	App domain	MyWebApp.exe
{cpu}	CPU core count	8
{mem}	Memory usage (MB)	256
{uptime}	Process uptime	02:45:30
{correlation}	Correlation ID	abc-123-def
{source}	Log source	UserService

🔧 Configuration Examples

Production Configuration

LoggingModule log = new LoggingModule("prod-syslog", 514, enableConsole: false);

// Set appropriate filters
log.Settings.MinimumSeverity = Severity.Warning;
log.Settings.MaxMessageLength = 8192;

// Structured logging for analysis
await log.BeginStructuredLog(Severity.Info, "Application started")
    .WithProperty("Version", Assembly.GetExecutingAssembly().GetName().Version)
    .WithProperty("Environment", Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT"))
    .WithProperty("MachineName", Environment.MachineName)
    .WriteAsync();

Development Configuration

LoggingModule log = new LoggingModule("localhost", 514, enableConsole: true);

// Immediate feedback for development
log.Settings.EnableColors = true;
log.Settings.MinimumSeverity = Severity.Debug;

// File logging for detailed debugging
log.Settings.FileLogging = FileLoggingMode.FileWithDate;
log.Settings.LogFilename = "./logs/debug.log";

High-Concurrency Configuration

LoggingModule log = new LoggingModule("logserver", 514, enableConsole: true);

// Thread-safe operations
log.Settings.EnableColors = true;

Task.Run(async () =>
{
    while (true)
    {
        // Even rapid server changes are thread-safe
        log.Servers = GetAvailableServers();
        await Task.Delay(1000);
    }
});

// Multiple threads can safely log concurrently
Parallel.For(0, 1000, i =>
{
    log.Info($"Concurrent message from thread {Thread.CurrentThread.ManagedThreadId}: {i}");
});

🧪 Testing

Run the comprehensive test suite:

cd src/Test
dotnet run

The test program validates each library capability including:

• ✅ All constructor patterns and validation
• ✅ Sync and async logging methods
• ✅ Structured logging with properties and correlation IDs
• ✅ Comprehensive thread safety under concurrent load
• ✅ Multiple destination delivery (syslog + console + file)
• ✅ Error handling and edge cases
• ✅ Performance benchmarks
• ✅ SyslogServer integration and end-to-end testing

🤝 Help or Feedback

Found a bug or have a feature request? File an issue - we'd love to hear from you!

🙏 Special Thanks

We'd like to extend a special thank you to those that have helped make this library better: @dev-jan @jisotalo

📜 Version History

Please refer to CHANGELOG.md for detailed version history.

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