feat: 좋아요 등록 동시성 테스트

Author: Kimjipang

apps/commerce-api/src/test/java/com/loopers/domain/like/LikeConcurrencyIntegrationTest.java

@@ -0,0 +1,51 @@
+package com.loopers.domain.like;
+
+import com.loopers.application.like.LikeFacade;
+import com.loopers.interfaces.api.like.LikeV1Dto;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest
+@Transactional
+public class LikeConcurrencyIntegrationTest {
+
+    @Autowired
+    private LikeFacade likeFacade;
+
+    @Autowired
+    private LikeRepository likeRepository;
+
+    @Test
+    void 동시에_100개의_좋아요요청이_들어오면_좋아요는_1개만_생성된다() throws Exception {
+        Long userId = 1L;
+        Long productId = 1L;
+
+        int threadCount = 100;
+        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
+        CountDownLatch latch = new CountDownLatch(threadCount);
+
+        for (int i = 0; i < threadCount; i++) {
+            executor.submit(() -> {
+                try {
+                    likeFacade.doLike(new LikeV1Dto.LikeRequest(userId, productId));
+                } finally {
+                    latch.countDown();
+                }
+            });
+        }
+
+        // 모든 스레드 작업이 종료될 때까지 대기
+        latch.await();
+
+        long count = likeRepository.countByUserIdAndProductId(userId, productId);
+        assertThat(count).isEqualTo(1);
+    }
+}