Late4dTrain.CronTimer

CronTimer

CronTimer is a simple and lightweight library for creating cron jobs in .NET. It provides functionality similar to System.Timer but uses cron expressions to schedule tasks.

Features

• Schedule tasks using cron expressions.
• Supports both synchronous and asynchronous operations.
• Integrates with Microsoft.Extensions.Logging for logging.
• Supports dependency injection.

Installation

You can install the CronTimer library via NuGet:

dotnet add package Late4dTrain.CronTimer

Usage

Basic Usage

Here's a basic example of how to use the CronTimer:

using System;
using System.Threading;
using System.Threading.Tasks;
using Late4dTrain.CronTimer;
using Late4dTrain.CronTimer.Events;

class Program
{
    static async Task Main(string[] args)
    {
        var timer = new CronTimer("*/1 * * * * *", CronFormats.IncludeSeconds);
        timer.TriggeredEventHandler += async (s, e) => await HandleCronTimer(e);
        timer.Start();

        // Let the timer run for 7 seconds
        await Task.Delay(TimeSpan.FromSeconds(7));
        await timer.StopAsync(CancellationToken.None);
    }

    private static Task HandleCronTimer(CronEventArgs e)
    {
        if (e.CancellationToken.IsCancellationRequested)
            return Task.CompletedTask;

        return Task.Run(() => { Console.WriteLine("Task has completed at {0}.", DateTime.UtcNow); });
    }
}

Using Dependency Injection and Logging

To use CronTimer with dependency injection and logging, follow these steps:

• Add the necessary NuGet packages:

  dotnet add package Microsoft.Extensions.Logging
  dotnet add package Microsoft.Extensions.DependencyInjection
  

• Configure the services in your Startup class:

  using Microsoft.Extensions.DependencyInjection;
  using Microsoft.Extensions.Logging;
  
  public class Startup
  {
      public void ConfigureServices(IServiceCollection services)
      {
          services.AddLogging(configure => configure.AddConsole());
  
          services.AddSingleton<ITimeProvider, SystemTimeProvider>();
          services.AddSingleton<IDelayProvider, SystemDelayProvider>();
  
          services.AddTransient<CronTimer>(provider =>
          {
              var logger = provider.GetRequiredService<ILogger<CronTimer>>();
              var timeProvider = provider.GetService<ITimeProvider>();
              var delayProvider = provider.GetService<IDelayProvider>();
  
              return new CronTimer(options =>
              {
                  options.AddCronTabs(new CronTab("*/5 * * * * *", CronFormats.IncludeSeconds));
              }, timeProvider, delayProvider, logger);
          });
      }
  }
  

• Use the CronTimer in your application:

  using System;
  using System.Threading;
  using System.Threading.Tasks;
  using Microsoft.Extensions.DependencyInjection;
  using Microsoft.Extensions.Logging;
  
  class Program
  {
      static async Task Main(string[] args)
      {
          var serviceProvider = new ServiceCollection()
              .AddLogging(configure => configure.AddConsole())
              .AddSingleton<ITimeProvider, SystemTimeProvider>()
              .AddSingleton<IDelayProvider, SystemDelayProvider>()
              .AddTransient<CronTimer>(provider =>
              {
                  var logger = provider.GetRequiredService<ILogger<CronTimer>>();
                  var timeProvider = provider.GetService<ITimeProvider>();
                  var delayProvider = provider.GetService<IDelayProvider>();
  
                  return new CronTimer(options =>
                  {
                      options.AddCronTabs(new CronTab("*/5 * * * * *", CronFormats.IncludeSeconds));
                  }, timeProvider, delayProvider, logger);
              })
              .BuildServiceProvider();
  
          var timer = serviceProvider.GetRequiredService<CronTimer>();
          timer.TriggeredEventHandler += async (s, e) => await HandleCronTimer(e);
          timer.Start();
  
          // Let the timer run for 7 seconds
          await Task.Delay(TimeSpan.FromSeconds(7));
          await timer.StopAsync(CancellationToken.None);
      }
  
      private static Task HandleCronTimer(CronEventArgs e)
      {
          if (e.CancellationToken.IsCancellationRequested)
              return Task.CompletedTask;
  
          return Task.Run(() => { Console.WriteLine("Task has completed at {0}.", DateTime.UtcNow); });
      }
  }
  

License

This project is licensed under the MIT License. See the LICENSE file for more details.

This README.md provides an overview of the CronTimer library, installation instructions, basic usage examples, and instructions for using dependency injection and logging.