Rename Vexer to Excititor

src/StellaOps.Excititor.Worker/Scheduling/VexWorkerHostedService.cs

@@ -0,0 +1,110 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using StellaOps.Excititor.Worker.Options;
+
+namespace StellaOps.Excititor.Worker.Scheduling;
+
+internal sealed class VexWorkerHostedService : BackgroundService
+{
+    private readonly IOptions<VexWorkerOptions> _options;
+    private readonly IVexProviderRunner _runner;
+    private readonly ILogger<VexWorkerHostedService> _logger;
+    private readonly TimeProvider _timeProvider;
+
+    public VexWorkerHostedService(
+        IOptions<VexWorkerOptions> options,
+        IVexProviderRunner runner,
+        ILogger<VexWorkerHostedService> logger,
+        TimeProvider timeProvider)
+    {
+        _options = options ?? throw new ArgumentNullException(nameof(options));
+        _runner = runner ?? throw new ArgumentNullException(nameof(runner));
+        _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+        _timeProvider = timeProvider ?? throw new ArgumentNullException(nameof(timeProvider));
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        var schedules = _options.Value.ResolveSchedules();
+        if (schedules.Count == 0)
+        {
+            _logger.LogWarning("Excititor worker has no configured provider schedules; the service will remain idle.");
+            await Task.CompletedTask;
+            return;
+        }
+
+        _logger.LogInformation("Excititor worker starting with {ProviderCount} provider schedule(s).", schedules.Count);
+
+        var tasks = new List<Task>(schedules.Count);
+        foreach (var schedule in schedules)
+        {
+            tasks.Add(RunScheduleAsync(schedule, stoppingToken));
+        }
+
+        await Task.WhenAll(tasks);
+    }
+
+    private async Task RunScheduleAsync(VexWorkerSchedule schedule, CancellationToken cancellationToken)
+    {
+        try
+        {
+            if (schedule.InitialDelay > TimeSpan.Zero)
+            {
+                _logger.LogInformation(
+                    "Provider {ProviderId} initial delay of {InitialDelay} before first execution.",
+                    schedule.ProviderId,
+                    schedule.InitialDelay);
+
+                await Task.Delay(schedule.InitialDelay, cancellationToken).ConfigureAwait(false);
+            }
+
+            using var timer = new PeriodicTimer(schedule.Interval);
+            do
+            {
+                var startedAt = _timeProvider.GetUtcNow();
+                _logger.LogInformation(
+                    "Provider {ProviderId} run started at {StartedAt}. Interval={Interval}.",
+                    schedule.ProviderId,
+                    startedAt,
+                    schedule.Interval);
+
+                try
+                {
+                    await _runner.RunAsync(schedule.ProviderId, cancellationToken).ConfigureAwait(false);
+
+                    var completedAt = _timeProvider.GetUtcNow();
+                    var elapsed = completedAt - startedAt;
+
+                    _logger.LogInformation(
+                        "Provider {ProviderId} run completed at {CompletedAt} (duration {Duration}).",
+                        schedule.ProviderId,
+                        completedAt,
+                        elapsed);
+                }
+                catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested)
+                {
+                    _logger.LogInformation("Provider {ProviderId} run cancelled.", schedule.ProviderId);
+                    break;
+                }
+                catch (Exception ex)
+                {
+                    _logger.LogError(
+                        ex,
+                        "Provider {ProviderId} run failed: {Message}",
+                        schedule.ProviderId,
+                        ex.Message);
+                }
+            }
+            while (await timer.WaitForNextTickAsync(cancellationToken).ConfigureAwait(false));
+        }
+        catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested)
+        {
+            _logger.LogInformation("Provider {ProviderId} schedule cancelled.", schedule.ProviderId);
+        }
+    }
+}