feat: 예약을 듣는 유스케이스 등록

src/data/repositories/BookingRepository.ts

@@ -17,37 +17,64 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-import Config from '../../common/Config';
 import axios from 'axios';
-import {plainToClass} from 'class-transformer';
-import BookingOption from '../../domain/entities/BookingOption';
+import Config from '../../common/Config';
 import Booking from '../../domain/entities/Booking';
+import EventSource from 'react-native-event-source';
+import BookingOption from '../../domain/entities/BookingOption';
+import {plainToClass} from 'class-transformer';
 
 export default class BookingRepository {
   static instance = new BookingRepository();
 
   private url = {
     options: (cafeteriaId: number) => `${Config.baseUrl}/booking/options?cafeteriaId=${cafeteriaId}`,
-    bookings: `${Config.baseUrl}/booking/bookings`,
+    bookings: (sse: boolean = false) => `${Config.baseUrl}/booking/bookings?sse=${sse}`,
     bookingsWithId: (bookingId: number) => `${Config.baseUrl}/booking/bookings/${bookingId}`,
   };
 
+  private previousEventSource?: EventSource = undefined;
+
   async getBookingOptions(cafeteriaId: number) {
     return plainToClass(BookingOption, (await axios.get(this.url.options(cafeteriaId))).data as any[], {
       excludeExtraneousValues: true,
     });
   }
 
   async makeBooking(params: Record<string, any>) {
-    await axios.post(this.url.bookings, params);
+    await axios.post(this.url.bookings(), params);
   }
 
   async getMyBookings() {
-    return plainToClass(Booking, (await axios.get(this.url.bookings)).data as any[], {
+    return plainToClass(Booking, (await axios.get(this.url.bookings())).data as any[], {
       excludeExtraneousValues: true,
     });
   }
 
+  listenForMyBookings(onBookings: (bookings: Booking[]) => void) {
+    this.previousEventSource?.close();
+
+    const eventSource = new EventSource(this.url.bookings(true), {withCredentials: true});
+
+    eventSource.addEventListener('bookings', event => {
+      const payload = event['data'] as string;
+
+      const bookings = plainToClass(Booking, JSON.parse(payload) as any[], {
+        excludeExtraneousValues: true,
+      });
+
+      onBookings(bookings);
+    });
+
+    this.previousEventSource = eventSource;
+  }
+
+  stopListeningForMyBookings() {
+    this.previousEventSource?.removeAllListeners();
+    this.previousEventSource?.close();
+    this.previousEventSource = undefined;
+  }
+
   async cancelBooking(bookingId: number) {
     await axios.delete(this.url.bookingsWithId(bookingId));
   }

src/domain/usecases/GetMyBookings.ts

@@ -21,6 +21,9 @@ import UseCase from './UseCase';
 import Booking from '../entities/Booking';
 import BookingRepository from '../../data/repositories/BookingRepository';
 
+/**
+ * REST 요청으로 예약 내역을 즉시 가져옵니다.
+ */
 class GetMyBookings extends UseCase<void, Booking[]> {
   constructor(private readonly bookingRepository: BookingRepository) {
     super();

src/domain/usecases/ListenForMyBookings.ts

@@ -0,0 +1,46 @@
+/**
+ * This file is part of INU Cafeteria.
+ *
+ * Copyright 2021 INU Global App Center <potados99@gmail.com>
+ *
+ * INU Cafeteria is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * INU Cafeteria is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import UseCase from './UseCase';
+import Booking from '../entities/Booking';
+import BookingRepository from '../../data/repositories/BookingRepository';
+
+type Params = {
+  onBookings?: (bookings: Booking[]) => void;
+};
+
+/**
+ * SSE로 예약 내역을 구독합니다.
+ * 인자로 undefined를 넘기면 구독 중단입니다.
+ */
+class ListenForMyBookings extends UseCase<Params, void> {
+  constructor(private readonly bookingRepository: BookingRepository) {
+    super();
+  }
+
+  async onExecute({onBookings}: Params): Promise<void> {
+    if (onBookings == null) {
+      this.bookingRepository.stopListeningForMyBookings();
+    } else {
+      this.bookingRepository.listenForMyBookings(onBookings);
+    }
+  }
+}
+
+export default new ListenForMyBookings(BookingRepository.instance);