Worker Services in .NET

A worker service is a .NET project built using a template which supplies a few useful features that turn a regular console application into something more powerful. A worker service runs on top of the concept of a host, which maintains the lifetime of the application. The host also makes available some familiar features, such as dependency injection, logging and configuration.

Worker services will generally be long-running services, performing some regularly occurring workload.

There are numerous reasons for creating long-running services such as:

Processing CPU intensive data.
Queuing work items in the background.
Performing a time-based operation on a schedule.

Program.cs

public class Program
{
    public static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }

    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureServices((hostContext, services) =>
            {
                services.AddHostedService<Worker>();
            });
}

appsettings.json

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  }
}

Worker.cs

public class Worker : BackgroundService
{
    private readonly ILogger<Worker> _logger;

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

    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        while (!stoppingToken.IsCancellationRequested)
        {
            _logger.LogInformation("Worker running at: {time}", DateTimeOffset.Now);
            await Task.Delay(1000, stoppingToken);
        }
    }
}

Register an IHostedService

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host.CreateDefaultBuilder(args)
        .ConfigureServices((hostContext, services) =>
        {
            services.AddHostedService<Worker>();
        });

References
https://docs.microsoft.com/en-us/dotnet/core/extensions/workers
https://www.stevejgordon.co.uk/what-are-dotnet-worker-services
https://docs.microsoft.com/en-us/aspnet/core/fundamentals/host/hosted-services?view=aspnetcore-6.0&tabs=visual-studio