Fuchs_Intranet/.github/instructions/periodic_service.instructions.md

applyTo

applyTo
Fuchs_DataService/**

PeriodicHostedService Instructions

Overview

PeriodicHostedService (Fuchs_DataService/PeriodicHostedService.cs) is a BackgroundService that runs multiple independent jobs, each on its own PeriodicTimer. It is started and stopped by the Topshelf FdsService (see topshelf.instructions.md).

Job Definition

Each job is a PeriodicJobDefinition record:

public sealed record PeriodicJobDefinition(
    string Name,
    TimeSpan Interval,
    Func<CancellationToken, Task> Execute);

Registering Jobs

Jobs are created in FdsService constructor and passed to PeriodicHostedService:

var interval = TimeSpan.FromMinutes(FdsConfig.ExecutionFrequency_Minutes);
var jobs = new[]
{
    new PeriodicJobDefinition("MfrSync", interval, async ct =>
    {
        await mfr.UpdateIfNecessary_async(debug);
        await mfr.UpdateRequested_async(debug);
        await mfr.GetInvoiceFiles_async(debug);
    }),
    // Add more jobs with different schedules here:
    // new PeriodicJobDefinition("HourlyJob", TimeSpan.FromHours(1), async ct => { ... })
};

Schedules

• Each job runs on its own independent PeriodicTimer — schedules do not interfere.
• Frequencies are configured in appsettings.json under the Fds section (e.g. Fds:ExecutionFrequency_Minutes).
• Add new config keys for additional job intervals as needed.

Error Handling

• Each job's Execute delegate is wrapped in a try/catch inside RunJobAsync.
• OperationCanceledException propagates normally (signals shutdown).
• All other exceptions are caught, logged via ILogger, and the job continues on its next tick.

Cancellation

• PeriodicHostedService respects the CancellationToken passed to StartAsync.
• FdsService.Stop() cancels the token, then awaits StopAsync(CancellationToken.None).

Adding a New Job

1. Optionally add a new frequency key to appsettings.json and read it via FdsConfig.
2. Add a new PeriodicJobDefinition to the jobs array in FdsService.
3. No changes to PeriodicHostedService itself are needed.