How to write a linux daemon with .Net Core

Question

I could just write a long-running CLI app and run it, but I\'m assuming it wouldn\'t comply to all the expectations one would have of a standards-compliant linux daemon (respond

Answer 1

Implementing Linux Daemon or service for windows quite easy with single codebase using Visual Studio 2019. Just create project using WorkerService template. In my case I have Coraval library to schedule the tasks.

Program.cs class

public class Program
{
    public static void Main(string[] args)
    {
        Log.Logger = new LoggerConfiguration()
                .MinimumLevel.Debug()
                .MinimumLevel.Override("Microsoft", LogEventLevel.Warning)
                .Enrich.FromLogContext()
                .WriteTo.File(@"C:\temp\Workerservice\logfile.txt").CreateLogger();

        IHost host = CreateHostBuilder(args).Build();

        host.Services.UseScheduler(scheduler =>
        {

            scheduler
              .Schedule()
              .EveryThirtySeconds();
        });
        host.Run();
    }
    public static IHostBuilder CreateHostBuilder(string[] args) =>
          Host.CreateDefaultBuilder(args).UseSystemd() //.UseWindowsService()

        .ConfigureServices(services =>
        {
            services.AddScheduler();
            services.AddTransient();
        });
}

ReprocessInvocable.cs class

public class ReprocessInvocable : IInvocable
{
    private readonly ILogger _logger;
    public ReprocessInvocable(ILogger logger)
    {
        _logger = logger;
    }
    public async Task Invoke()
    {
        //your code goes here
        _logger.LogInformation("Information - Worker running at: {time}", DateTimeOffset.Now);
        _logger.LogWarning("Warning - Worker running at: {time}", DateTimeOffset.Now);
        _logger.LogCritical("Critical - Worker running at: {time}", DateTimeOffset.Now);
        Log.Information("Invoke has called at: {time}", DateTimeOffset.Now);
    }
}

For linux daemon use UseSystemd and for windows service use UseWindowsService as per the above code.