feat: ScheduleWorker 구현 (#112)

Reviewed-on: https://git.ipstein.myds.me/SPMS/SPMS_API/pulls/113

SPMS.Infrastructure/DependencyInjection.cs

@@ -70,6 +70,7 @@ public static class DependencyInjection
 
         // Workers
         services.AddHostedService<PushWorker>();
+        services.AddHostedService<ScheduleWorker>();
 
         // Token Store & Email Service
         services.AddMemoryCache();

SPMS.Infrastructure/Workers/ScheduleWorker.cs

@@ -0,0 +1,142 @@
+using System.Globalization;
+using System.Text;
+using System.Text.Json;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using RabbitMQ.Client;
+using RabbitMQ.Client.Events;
+using SPMS.Application.DTOs.Push;
+using SPMS.Application.Interfaces;
+using SPMS.Application.Settings;
+using SPMS.Infrastructure.Messaging;
+
+namespace SPMS.Infrastructure.Workers;
+
+public class ScheduleWorker : BackgroundService
+{
+    private const int PollingIntervalSeconds = 30;
+
+    private readonly RabbitMQConnection _rabbitConnection;
+    private readonly RabbitMQSettings _rabbitSettings;
+    private readonly IServiceScopeFactory _scopeFactory;
+    private readonly ILogger<ScheduleWorker> _logger;
+
+    public ScheduleWorker(
+        RabbitMQConnection rabbitConnection,
+        IOptions<RabbitMQSettings> rabbitSettings,
+        IServiceScopeFactory scopeFactory,
+        ILogger<ScheduleWorker> logger)
+    {
+        _rabbitConnection = rabbitConnection;
+        _rabbitSettings = rabbitSettings.Value;
+        _scopeFactory = scopeFactory;
+        _logger = logger;
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        _logger.LogInformation("ScheduleWorker 시작 (폴링 간격: {Interval}초)", PollingIntervalSeconds);
+
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            try
+            {
+                await PollScheduleQueueAsync(stoppingToken);
+            }
+            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
+            {
+                break;
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "ScheduleWorker 오류 — 5초 후 재시도");
+            }
+
+            await Task.Delay(TimeSpan.FromSeconds(PollingIntervalSeconds), stoppingToken);
+        }
+
+        _logger.LogInformation("ScheduleWorker 종료");
+    }
+
+    private async Task PollScheduleQueueAsync(CancellationToken ct)
+    {
+        await using var channel = await _rabbitConnection.CreateChannelAsync(ct);
+        await channel.BasicQosAsync(0, 100, false, ct);
+
+        int processedCount = 0;
+        int requeuedCount = 0;
+
+        while (!ct.IsCancellationRequested)
+        {
+            var result = await channel.BasicGetAsync(_rabbitSettings.ScheduleQueue, false, ct);
+            if (result == null)
+                break;
+
+            try
+            {
+                var body = Encoding.UTF8.GetString(result.Body.ToArray());
+                var scheduleMessage = JsonSerializer.Deserialize<ScheduleMessageDto>(body);
+
+                if (scheduleMessage == null)
+                {
+                    _logger.LogWarning("Schedule 메시지 역직렬화 실패 — ACK 후 스킵");
+                    await channel.BasicAckAsync(result.DeliveryTag, false, ct);
+                    continue;
+                }
+
+                var scheduledAt = ParseScheduledAt(scheduleMessage.ScheduledAt);
+                if (scheduledAt == null)
+                {
+                    _logger.LogWarning("scheduled_at 파싱 실패: {Value} — ACK 후 스킵", scheduleMessage.ScheduledAt);
+                    await channel.BasicAckAsync(result.DeliveryTag, false, ct);
+                    continue;
+                }
+
+                // 아직 예약 시간이 도래하지 않음 → NACK + requeue
+                if (scheduledAt.Value > DateTime.UtcNow)
+                {
+                    await channel.BasicNackAsync(result.DeliveryTag, false, true, ct);
+                    requeuedCount++;
+                    continue;
+                }
+
+                // 예약 시간 도래 → push queue로 전달
+                using var scope = _scopeFactory.CreateScope();
+                var pushQueueService = scope.ServiceProvider.GetRequiredService<IPushQueueService>();
+                await pushQueueService.PublishPushMessageAsync(scheduleMessage.PushMessage, ct);
+
+                await channel.BasicAckAsync(result.DeliveryTag, false, ct);
+                processedCount++;
+
+                _logger.LogInformation(
+                    "예약 메시지 발송 전달: scheduleId={ScheduleId}, messageId={MessageId}",
+                    scheduleMessage.ScheduleId, scheduleMessage.MessageId);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Schedule 메시지 처리 중 오류");
+                await channel.BasicNackAsync(result.DeliveryTag, false, true, ct);
+            }
+        }
+
+        if (processedCount > 0 || requeuedCount > 0)
+        {
+            _logger.LogInformation(
+                "ScheduleWorker 폴링 완료: 처리={Processed}, 대기={Requeued}",
+                processedCount, requeuedCount);
+        }
+    }
+
+    private static DateTime? ParseScheduledAt(string value)
+    {
+        if (DateTime.TryParse(value, CultureInfo.InvariantCulture, DateTimeStyles.AdjustToUniversal, out var dt))
+            return dt;
+
+        if (DateTimeOffset.TryParse(value, CultureInfo.InvariantCulture, DateTimeStyles.None, out var dto))
+            return dto.UtcDateTime;
+
+        return null;
+    }
+}