refactor: replay metrics come from spans, and ReplayMetrics is gone

backend/app/core/dishka_lifespan.py

@@ -15,6 +15,7 @@
 from app.core.tracing import Tracer
 from app.db.docs import ALL_DOCUMENTS
 from app.events.handlers import notification_router, sse_router
+from app.services.event_replay import EventReplayService
 from app.services.notification_scheduler import NotificationScheduler
 from app.settings import Settings
 
@@ -64,24 +65,33 @@ async def lifespan(app: FastAPI) -> AsyncGenerator[None, None]:
     await broker.start()
     logger.info("Kafka broker started")
 
-    # Set up APScheduler for NotificationScheduler
+    # Set up APScheduler for NotificationScheduler and the replay session report
     notification_scheduler: NotificationScheduler = await container.get(NotificationScheduler)
-    notification_apscheduler = AsyncIOScheduler()
-    notification_apscheduler.add_job(
+    replay_service: EventReplayService = await container.get(EventReplayService)
+    apscheduler = AsyncIOScheduler()
+    apscheduler.add_job(
         notification_scheduler.process_due_notifications,
         trigger="interval",
         seconds=15,
         id="process_due_notifications",
         max_instances=1,
         misfire_grace_time=60,
     )
-    notification_apscheduler.start()
+    apscheduler.add_job(
+        replay_service.report_sessions,
+        trigger="interval",
+        seconds=10,
+        id="report_replay_sessions",
+        max_instances=1,
+        misfire_grace_time=30,
+    )
+    apscheduler.start()
     logger.info("NotificationScheduler started (APScheduler interval=15s)")
 
     try:
         yield
     finally:
-        notification_apscheduler.shutdown(wait=False)
+        apscheduler.shutdown(wait=False)
         logger.info("NotificationScheduler stopped")
         await broker.stop()
         logger.info("Kafka broker stopped")

backend/app/core/metrics/__init__.py

@@ -3,7 +3,6 @@
 from app.core.metrics.database import IdempotencyMetrics
 from app.core.metrics.events import EventMetrics
 from app.core.metrics.rate_limit import RateLimitMetrics
-from app.core.metrics.replay import ReplayMetrics
 from app.core.metrics.security import SecurityMetrics
 
 __all__ = [
@@ -12,7 +11,6 @@
     "IdempotencyMetrics",
     "EventMetrics",
     "RateLimitMetrics",
-    "ReplayMetrics",
     "SecurityMetrics",
     "setup_metrics",
 ]

backend/app/core/providers.py

@@ -17,7 +17,6 @@
     EventMetrics,
     IdempotencyMetrics,
     RateLimitMetrics,
-    ReplayMetrics,
     SecurityMetrics,
 )
 from app.core.security import SecurityService
@@ -266,10 +265,6 @@ def get_rate_limit_metrics(self, settings: Settings) -> RateLimitMetrics:
     def get_idempotency_metrics(self, settings: Settings) -> IdempotencyMetrics:
         return IdempotencyMetrics(settings)
 
-    @provide
-    def get_replay_metrics(self, settings: Settings) -> ReplayMetrics:
-        return ReplayMetrics(settings)
-
     @provide
     def get_security_metrics(self, settings: Settings) -> SecurityMetrics:
         return SecurityMetrics(settings)
@@ -708,14 +703,14 @@ def get_event_replay_service(
         self,
         replay_repository: ReplayRepository,
         kafka_producer: UnifiedProducer,
-        replay_metrics: ReplayMetrics,
+        tracer: trace.Tracer,
         logger: structlog.stdlib.BoundLogger,
         sse_bus: SSERedisBus,
     ) -> EventReplayService:
         return EventReplayService(
             repository=replay_repository,
             producer=kafka_producer,
-            replay_metrics=replay_metrics,
+            tracer=tracer,
             logger=logger,
             sse_bus=sse_bus,
         )