setup-background-job

Setup Background Job

Guide for creating scheduled background jobs using Quartz.NET.

When to Use

• Periodic tasks (email polling, data sync, cleanup)
• Scheduled operations (daily reports, reminders)
• Recurring background processing
• Cron-based job scheduling

Job Implementation

public class EmailPollingJob : IJob
{
    private readonly IEmailService _emailService;
    private readonly ILogger<EmailPollingJob> _logger;
    
    public EmailPollingJob(IEmailService emailService, ILogger<EmailPollingJob> logger)
    {
        _emailService = emailService;
        _logger = logger;
    }
    
    public async Task Execute(IJobExecutionContext context)
    {
        _logger.LogInformation("Email polling job started");
        
        try
        {
            await _emailService.PollNewEmails();
            _logger.LogInformation("Email polling completed successfully");
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error polling emails");
            throw new JobExecutionException(ex, refireImmediately: false);
        }
    }
}

Job Registration

// In Program.cs or Startup.cs
services.AddQuartz(q =>
{
    q.UseMicrosoftDependencyInjectionJobFactory();
    
    // Define the job
    var jobKey = new JobKey("EmailPollingJob");
    q.AddJob<EmailPollingJob>(opts => opts.WithIdentity(jobKey));
    
    // Create a trigger
    q.AddTrigger(opts => opts
        .ForJob(jobKey)
        .WithIdentity("EmailPollingTrigger")
        .WithCronSchedule("0 */5 * * * ?")); // Every 5 minutes
});

services.AddQuartzHostedService(q => q.WaitForJobsToComplete = true);

Cron Expressions

Common patterns:

0 0 8 * * ?        - Every day at 8:00 AM
0 */5 * * * ?      - Every 5 minutes
0 30 17 * * ?      - Every day at 5:30 PM
0 0 0 ? * SUN      - Every Sunday at midnight
0 0 * * * ?        - Every hour
0 */30 * * * ?     - Every 30 minutes
0 0 1 1 * ?        - First day of month at 1:00 AM

Format: second minute hour day-of-month month day-of-week