Can you create a schedule jobs solution?

[andrerocha]

I need create a schedule jobs. This is possible using the same structure?

Maybe use job worker or any other idea as quartz etc..

Anybody have any idea?

[neman]

Yes it is possible. I used background tasks, which executes commands from Application layer.

[litan1106]

I used Hangfire with Mediatr. it worked great.

[shobhitvaish]

I used Hangfire with Mediatr. it worked great.

Mind sharing an example?

[MARKUSER]

1. I am looking for some help on the same. Using this project template i have started building the code. I have API project and at the same time i wanted to create .net core WorkerService (like windows application) to process CSV and EXCEL files. Any pointers to using this template with WorkerService will be of great help.
2. I would like to create some reusable logic between API and WorkerService so is it a good idea to create new libraries and call them from Application layer handlers ?

[MARKUSER]

Yes it is possible. I used background tasks, which executes commands from Application layer.

@neman any help ?

[fakhrulhilal]

I never implement background job using clean architecture. But I ever implement background job using hangfire. Basically, we just register our action and let hangfire does the job. I'm thinking to create job executor abstraction in application layer, f.e

public delegate Task JobAction();
public interface IJobAgent
{
    void Queue(JobAction action, JobConfigs configs);
}

public abstract record JobConfigs
{
    public static OneTimeJobConfigs OneTime => new();
    public static OneTimeJobConfigs Delayed(TimeSpan delay) => new(delay);
    public static RecurringJobConfigs Scheduled(string schedule) => new(schedule);
}
public record OneTimeJobConfigs(TimeSpan? Delay = null) : JobConfigs;
public record RecurringJobConfigs(string Schedule) : JobConfigs;

And then in infra layer, we can use hangfire like this:

public class HangfireJobAgent : IJobAgent
{
    public void Queue(JobAction action, JobConfigs configs)
    {
        switch (configs)
        {
            case RecurringJobConfigs recurringJob:
                RecurringJob.AddOrUpdate(() => action(), recurringJob.CronSchedule);
                break;
            case OneTimeJobConfigs { Delay: not null } oneTimeJob:
                BackgroundJob.Schedule(() => action(), oneTimeJob.Delay.Value);
                break;
            case OneTimeJobConfigs:
                BackgroundJob.Enqueue(() => action());
                break;
        }
    }
}

public static class DependencyInjection
{
    public static IServiceCollection AddAgentJob(this IServiceCollection services) => services
        // Add Hangfire services.
        .AddHangfire(configuration => configuration
            .SetDataCompatibilityLevel(CompatibilityLevel.Version_170)
            .UseSimpleAssemblyNameTypeSerializer()
            .UseRecommendedSerializerSettings()
            // choose your job storage options
            .UseSQLiteStorage("yourConnectionString"))

        // Add the processing server as IHostedService
        .AddHangfireServer();
}

After that, we can use in request handler as follows:

public record MyRequest : IRequest;
public class MyRequestHandler : IRequestHandler<MyRequest>
{
    private readonly IJobAgent _jobAgent;

    public MyRequestHandler(IJobAgent jobAgent)
    {
        _jobAgent = jobAgent;
    }

    public Task<Unit> Handle(MyRequest request, CancellationToken cancellationToken)
    {
        // register task next hour
        _jobAgent.Queue(() => Task.CompletedTask, JobConfigs.Delayed(TimeSpan.FromHours(1)));
        return Task.FromResult(Unit.Value);
    }
}

Note that, I never tried this, please test before using. This's just my idea.

[artworkad]

@fakhrulhilal thx for the example. Had to make following changes to make it work.

Method call expressions are not supported with Hangfire

• Using method call expressions on client-side HangfireIO/Hangfire#30
• https://discuss.hangfire.io/t/generate-a-methodcallexpression-to-pass-to-hangfire-enqueue/1017

Minor changes to make it work:

using System.Linq.Expressions;

public interface IJobService
{
    void Queue<T>(Expression<Action<T>> action, JobConfigs configs);
}

public class HangfireJobService : IJobService
{
    public void Queue<T>(Expression<Action<T>> action, JobConfigs configs)
    {
        switch (configs)
        {
            case OneTimeJobConfigs:
                BackgroundJob.Enqueue(action);
                break;
            case RecurringJobConfigs recurringJob:
                RecurringJob.AddOrUpdate(action, recurringJob.Schedule);
                break;
        }
    }
}

Start a job from e.g. a query like so:

_jobService.Queue<IReportService>(_reportService => _reportService .SomeMethod(request), JobConfigs.OneTime);