MiniCron.Core 1.0.0

MiniCron.Core

MiniCron.Core is a lightweight and simple library for scheduling background tasks in .NET applications using Cron expressions. It integrates seamlessly with the Microsoft.Extensions.DependencyInjection framework.

Features

• Simple & Lightweight: Minimal setup required.
• Dependency Injection: Access your services directly within your scheduled jobs.
• Async Support: Fully supports asynchronous tasks.
• Cancellation Support: Handles cancellation tokens gracefully.

Installation

Install the package via NuGet:

dotnet add package MiniCron.Core

Usage

1. Register MiniCron

In your Program.cs (or Startup.cs), register MiniCron services and define your jobs:

using MiniCron.Core.Extensions;

var builder = WebApplication.CreateBuilder(args);

// Register MiniCron
builder.Services.AddMiniCron(options =>
{
    // Run every minute
    options.AddJob("* * * * *", async (serviceProvider, cancellationToken) =>
    {
        Console.WriteLine($"Job executed at {DateTime.Now}");
        await Task.CompletedTask;
    });

    // Run every 5 minutes
    options.AddJob("*/5 * * * *", async (serviceProvider, cancellationToken) =>
    {
        // Resolve services from the DI container
        var logger = serviceProvider.GetRequiredService<ILogger<Program>>();
        logger.LogInformation("5-minute job executed.");
        
        await Task.Delay(100, cancellationToken);
    });
});

var app = builder.Build();
app.Run();

2. Using Scoped Services

Since the background service runs as a Singleton, you should create a scope to resolve Scoped services (like EF Core DbContexts):

builder.Services.AddMiniCron(options =>
{
    options.AddJob("0 12 * * *", async (serviceProvider, cancellationToken) =>
    {
        using var scope = serviceProvider.CreateScope();
        var myScopedService = scope.ServiceProvider.GetRequiredService<IMyScopedService>();
        
        await myScopedService.DoWorkAsync(cancellationToken);
    });
});

Cron Expressions

MiniCron supports standard cron expressions with 5 fields:

* * * * *
| | | | |
| | | | +----- Day of Week (0 - 6) (Sunday=0)
| | | +------- Month (1 - 12)
| | +--------- Day of Month (1 - 31)
| +----------- Hour (0 - 23)
+------------- Minute (0 - 59)

Examples:

• * * * * *: Every minute
• */5 * * * *: Every 5 minutes
• 0 0 * * *: Every day at midnight
• 0 12 * * 1: Every Monday at 12:00 PM

Made with ❤️ by jeanlrnt