Merge pull request #270 from boostcampwm-2024/feat/#269-sse-heart-beat

SSE 연결에서 하트비트 메시지 송신

back/src/domains/booking/const/sseMaximumInterval.ts

@@ -0,0 +1 @@
+export const SSE_MAXIMUM_INTERVAL = 30000;

back/src/domains/booking/service/booking-seats.service.ts

@@ -14,6 +14,7 @@ import { UserService } from '../../user/service/user.service';
 import { SEATS_BROADCAST_INTERVAL } from '../const/seatsBroadcastInterval.const';
 import { SEATS_SSE_RETRY_TIME } from '../const/seatsSseRetryTime.const';
 import { SeatStatus } from '../const/seatStatus.enum';
+import { SSE_MAXIMUM_INTERVAL } from '../const/sseMaximumInterval';
 import { SeatsSseDto } from '../dto/seatsSse.dto';
 import { runGetSeatsLua } from '../luaScripts/getSeatsLua';
 import { runInitSectionSeatLua } from '../luaScripts/initSectionSeatLua';
@@ -183,12 +184,26 @@ export class BookingSeatsService {
 
   private async createSeatSubscription(eventId: number, initialSeats: boolean[][]) {
     const subscription = new BehaviorSubject<SeatStatusObject>({ seatStatus: initialSeats });
-    setInterval(async () => {
-      if (this.isBroadcastActivated(eventId)) {
-        subscription.next(new SeatsSseDto(await this.getSeats(eventId)));
-        this.unActivateNextBroadcast(eventId);
-      }
-    }, SEATS_BROADCAST_INTERVAL);
+    let lastBroadcastTime = Date.now();
+
+    setInterval(
+      async () => {
+        const now = Date.now();
+        const timeSinceLastBroadcast = now - lastBroadcastTime;
+
+        if (timeSinceLastBroadcast >= SSE_MAXIMUM_INTERVAL || this.isBroadcastActivated(eventId)) {
+          const seats = await this.getSeats(eventId);
+          subscription.next(new SeatsSseDto(seats));
+          lastBroadcastTime = Date.now();
+
+          if (this.isBroadcastActivated(eventId)) {
+            this.unActivateNextBroadcast(eventId);
+          }
+        }
+      },
+      Math.min(SEATS_BROADCAST_INTERVAL, SSE_MAXIMUM_INTERVAL),
+    );
+
     return subscription;
   }
 }

back/src/domains/booking/service/waiting-queue.service.ts

@@ -6,6 +6,7 @@ import { map } from 'rxjs/operators';
 
 import { AuthService } from '../../../auth/service/auth.service';
 import { UserService } from '../../user/service/user.service';
+import { SSE_MAXIMUM_INTERVAL } from '../const/sseMaximumInterval';
 import { WAITING_BROADCAST_INTERVAL } from '../const/waitingBroadcastInterval.const';
 import { DEFAULT_WAITING_THROUGHPUT_RATE } from '../const/watingThroughputRate.const';
 import { WaitingSseDto } from '../dto/waitingSse.dto';
@@ -80,7 +81,7 @@ export class WaitingQueueService {
             DEFAULT_WAITING_THROUGHPUT_RATE,
           ),
         ),
-      WAITING_BROADCAST_INTERVAL,
+      Math.min(WAITING_BROADCAST_INTERVAL, SSE_MAXIMUM_INTERVAL),
     );
 
     this.queueSubscriptionMap.set(eventId, subscription);