如何使用“演员提醒”机制在服务结构中安排任务？

Question

I want to generate invoices on daily, weekly and monthly basis and want to send invoices periodically. Each customer have different invoice settings.

Answer 1

Sometime ago I wondered how to do that myself. Based on the excellent documentation I came up with a sample app, see my repo .

Your actor should implement the IRemindable interface. To create a reminder use this in an actor method:

await RegisterReminderAsync(
            "MyReminder", // name of the reminder
            Encoding.ASCII.GetBytes(message), // byte array with payload (message is a string in my case)
            dueTime, // When is the reminder first activated
            snoozeTime); // Interval between activations

In your case set the snoozeTime to a day or to a week to have the reminder activate every period.

When the due time is there the method ReceiveReminderAsync is called:

public Task ReceiveReminderAsync(string reminderName, byte[] state, TimeSpan dueTime, TimeSpan period)
{
    ActorEventSource.Current.Message($"Actor recieved reminder {reminderName}.");

    ...
}

You can tell by the value of ReceiveReminderAsync which reminder it is about and you can use the content of state to act on the payload.

To dismiss a reminder use the UnregisterReminderAsync method:

await UnregisterReminderAsync(GetReminder("MyReminder"));  

Answer 2

internal class InvoiceGenerationActor : Actor, IInvoiceGenerationActor, IRemindable
{
    protected override async Task OnActivateAsync()
    {
        ////ActorEventSource.Current.ActorMessage(this, "Actor activated.");

        //// The StateManager is this actor's private state store.
        //// Data stored in the StateManager will be replicated for high-availability for actors that use volatile or persisted state storage.
        //// Any serializable object can be saved in the StateManager.
        //// For more information, see https://aka.ms/servicefabricactorsstateserialization

        //// return this.StateManager.TryAddStateAsync("count", 0);

        ////var schedulerDtos = GetSchedulerList();

        await base.OnActivateAsync();

        ActorEventSource.Current.ActorMessage(this, "Actor activated.");

        IActorReminder generationReminderRegistration = await this.RegisterReminderAsync(GenerationRemainder, BitConverter.GetBytes(100), TimeSpan.FromMilliseconds(0), TimeSpan.FromMinutes(10));

        ////IActorReminder mailReminderRegistration = await this.RegisterReminderAsync(generationRemainder, BitConverter.GetBytes(100), TimeSpan.FromMinutes(1), TimeSpan.FromHours(1));

        return;
    }

    public async Task ReceiveReminderAsync(string reminderName, byte[] context, TimeSpan dueTime, TimeSpan period)
    {
        if (reminderName.Equals(GenerationRemainder))
        {
            await GetAllInvoiceSettingAndRegisterNewRemiders();
        }
        else
        {
            int solutionPartnerId = BitConverter.ToInt32(context, 0);
            var data = await Get("SolutionOwnerInvoiceGeneration/AutomaticInvoiceGeneration/" + solutionPartnerId, "PartnerService");
            await UnregisterReminderAsync(GetReminder(reminderName));
        }
    }
}

Answer 3

For scheduled tasks, you can use an external mechanism like hangfire .

It does scheduled tasks apart from the web app and you can track tasks from its task dashboard.

You can register a job like:

RecurringJob.AddOrUpdate(() => SoccerDataFetcher_UpdatePlayersOfTeams(), Cron.Daily);