[Hotfix/BE] 로그아웃 시 팔로워 수가 초기화 되는 현상을 수정한다

backend/src/main/java/com/woowacourse/f12/application/member/MemberService.java

@@ -3,12 +3,7 @@
 
 import com.woowacourse.f12.domain.inventoryproduct.InventoryProduct;
 import com.woowacourse.f12.domain.inventoryproduct.InventoryProductRepository;
-import com.woowacourse.f12.domain.member.CareerLevel;
-import com.woowacourse.f12.domain.member.Following;
-import com.woowacourse.f12.domain.member.FollowingRepository;
-import com.woowacourse.f12.domain.member.JobType;
-import com.woowacourse.f12.domain.member.Member;
-import com.woowacourse.f12.domain.member.MemberRepository;
+import com.woowacourse.f12.domain.member.*;
 import com.woowacourse.f12.dto.request.member.MemberRequest;
 import com.woowacourse.f12.dto.request.member.MemberSearchRequest;
 import com.woowacourse.f12.dto.response.member.LoggedInMemberResponse;
@@ -19,15 +14,16 @@
 import com.woowacourse.f12.exception.notfound.MemberNotFoundException;
 import com.woowacourse.f12.presentation.member.CareerLevelConstant;
 import com.woowacourse.f12.presentation.member.JobTypeConstant;
-import java.util.List;
-import java.util.Objects;
-import java.util.stream.Collectors;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Slice;
 import org.springframework.lang.Nullable;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
 @Service
 @Transactional(readOnly = true)
 public class MemberService {
@@ -136,7 +132,7 @@ private List<Long> extractMemberIds(final List<Member> members) {
 
     @Transactional
     public void follow(final Long followerId, final Long followingId) {
-        final Member followingMember = memberRepository.findById(followingId)
+        final Member targetMember = memberRepository.findById(followingId)
                 .orElseThrow(MemberNotFoundException::new);
         validateFollowingMembersExist(followerId);
         validateNotFollowing(followerId, followingId);
@@ -145,7 +141,7 @@ public void follow(final Long followerId, final Long followingId) {
                 .followingId(followingId)
                 .build();
         followingRepository.save(following);
-        increaseFollowerCount(followingMember);
+        targetMember.follow();
     }
 
     private void validateFollowingMembersExist(final Long followerId) {
@@ -160,35 +156,20 @@ private void validateNotFollowing(final Long followerId, final Long followingId)
         }
     }
 
-    private void increaseFollowerCount(final Member followingMember) {
-        final Member updatedMember = Member.builder()
-                .followerCount(followingMember.getFollowerCount() + 1)
-                .build();
-        followingMember.update(updatedMember);
-    }
-
     @Transactional
     public void unfollow(final Long followerId, final Long followingId) {
-        final Member followingMember = memberRepository.findById(followingId)
+        final Member targetMember = memberRepository.findById(followingId)
                 .orElseThrow(MemberNotFoundException::new);
         validateFollowingMembersExist(followerId);
         final Following following = findFollowingRelation(followerId, followingId);
         followingRepository.delete(following);
-        decreaseFollowerCount(followingMember);
+        targetMember.unfollow();
     }
 
     private Following findFollowingRelation(final Long followerId, final Long followingId) {
         return followingRepository.findByFollowerIdAndFollowingId(followerId, followingId)
                 .orElseThrow(NotFollowingException::new);
     }
-
-    private void decreaseFollowerCount(final Member followingMember) {
-        final Member updatedMember = Member.builder()
-                .followerCount(followingMember.getFollowerCount() - 1)
-                .build();
-        followingMember.update(updatedMember);
-    }
-
     public MemberPageResponse findFollowingsByConditions(final Long loggedInId, final MemberSearchRequest memberSearchRequest,
                                                          final Pageable pageable) {
         final Slice<Member> slice = findFollowingsBySearchConditions(loggedInId, memberSearchRequest, pageable);

backend/src/main/java/com/woowacourse/f12/domain/member/Member.java

@@ -70,7 +70,6 @@ public void update(final Member updateMember) {
         updateImageUrl(updateMember.imageUrl);
         updateCareerLevel(updateMember.careerLevel);
         updateJobType(updateMember.jobType);
-        updateFollowerCount(updateMember.followerCount);
         updateRegistered(updateMember.registered);
     }
 
@@ -98,11 +97,15 @@ private void updateJobType(final JobType jobType) {
         }
     }
 
-    private void updateFollowerCount(final int followerCount) {
-        if (followerCount < 0){
+    public void follow() {
+        this.followerCount += 1;
+    }
+
+    public void unfollow() {
+        if (this.followerCount == 0) {
             throw new InvalidFollowerCountException();
         }
-        this.followerCount = followerCount;
+        this.followerCount -= 1;
     }
 
     private void updateRegistered(final boolean registered) {

backend/src/test/java/com/woowacourse/f12/acceptance/MemberAcceptanceTest.java

@@ -1,22 +1,5 @@
 package com.woowacourse.f12.acceptance;
 
-import static com.woowacourse.f12.acceptance.support.RestAssuredRequestUtil.GET_요청을_보낸다;
-import static com.woowacourse.f12.acceptance.support.RestAssuredRequestUtil.로그인된_상태로_DELETE_요청을_보낸다;
-import static com.woowacourse.f12.acceptance.support.RestAssuredRequestUtil.로그인된_상태로_GET_요청을_보낸다;
-import static com.woowacourse.f12.acceptance.support.RestAssuredRequestUtil.로그인된_상태로_PATCH_요청을_보낸다;
-import static com.woowacourse.f12.acceptance.support.RestAssuredRequestUtil.로그인된_상태로_POST_요청을_보낸다;
-import static com.woowacourse.f12.domain.member.CareerLevel.JUNIOR;
-import static com.woowacourse.f12.domain.member.CareerLevel.SENIOR;
-import static com.woowacourse.f12.domain.member.JobType.BACKEND;
-import static com.woowacourse.f12.presentation.member.CareerLevelConstant.JUNIOR_CONSTANT;
-import static com.woowacourse.f12.presentation.member.CareerLevelConstant.SENIOR_CONSTANT;
-import static com.woowacourse.f12.presentation.member.JobTypeConstant.BACKEND_CONSTANT;
-import static com.woowacourse.f12.support.fixture.AcceptanceFixture.민초;
-import static com.woowacourse.f12.support.fixture.AcceptanceFixture.오찌;
-import static com.woowacourse.f12.support.fixture.AcceptanceFixture.코린;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.jupiter.api.Assertions.assertAll;
-
 import com.woowacourse.f12.domain.inventoryproduct.InventoryProduct;
 import com.woowacourse.f12.domain.member.Member;
 import com.woowacourse.f12.domain.product.Product;
@@ -26,6 +9,7 @@
 import com.woowacourse.f12.dto.response.auth.LoginResponse;
 import com.woowacourse.f12.dto.response.inventoryproduct.InventoryProductResponse;
 import com.woowacourse.f12.dto.response.inventoryproduct.InventoryProductsResponse;
+import com.woowacourse.f12.dto.response.member.LoggedInMemberResponse;
 import com.woowacourse.f12.dto.response.member.MemberPageResponse;
 import com.woowacourse.f12.dto.response.member.MemberResponse;
 import com.woowacourse.f12.dto.response.member.MemberWithProfileProductResponse;
@@ -34,11 +18,23 @@
 import com.woowacourse.f12.support.fixture.ReviewFixture;
 import io.restassured.response.ExtractableResponse;
 import io.restassured.response.Response;
-import java.util.List;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 
+import java.util.List;
+
+import static com.woowacourse.f12.acceptance.support.RestAssuredRequestUtil.*;
+import static com.woowacourse.f12.domain.member.CareerLevel.JUNIOR;
+import static com.woowacourse.f12.domain.member.CareerLevel.SENIOR;
+import static com.woowacourse.f12.domain.member.JobType.BACKEND;
+import static com.woowacourse.f12.presentation.member.CareerLevelConstant.JUNIOR_CONSTANT;
+import static com.woowacourse.f12.presentation.member.CareerLevelConstant.SENIOR_CONSTANT;
+import static com.woowacourse.f12.presentation.member.JobTypeConstant.BACKEND_CONSTANT;
+import static com.woowacourse.f12.support.fixture.AcceptanceFixture.*;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertAll;
+
 class MemberAcceptanceTest extends AcceptanceTest {
 
     @Autowired
@@ -640,6 +636,27 @@ class MemberAcceptanceTest extends AcceptanceTest {
         );
     }
 
+    @Test
+    void 재로그인_시_팔로워_수가_변하지_않는다() {
+        // given
+        MemberRequest memberRequest = new MemberRequest(SENIOR_CONSTANT, BACKEND_CONSTANT);
+        LoginResponse followingResponse = 민초.로그인을_한다();
+        민초.로그인한_상태로(followingResponse.getToken()).추가정보를_입력한다(memberRequest);
+
+        final LoginResponse followerResponse = 코린.로그인을_한다();
+        코린.로그인한_상태로(followerResponse.getToken()).추가정보를_입력한다(memberRequest);
+        코린.로그인한_상태로(followerResponse.getToken()).팔로우한다(followingResponse.getMember().getId());
+
+        final LoginResponse reLoggedInFollowingResponse = 민초.로그인을_한다();
+
+        // when
+        final LoggedInMemberResponse followingMemberResponse = 민초.로그인한_상태로(reLoggedInFollowingResponse.getToken()).자신의_프로필을_조회한다()
+                .as(LoggedInMemberResponse.class);
+
+        // then
+        assertThat(followingMemberResponse.getFollowerCount()).isOne();
+    }
+
     private Product 제품을_저장한다(Product product) {
         return productRepository.save(product);
     }

backend/src/test/java/com/woowacourse/f12/domain/member/MemberRepositoryTest.java

@@ -47,10 +47,7 @@ class MemberRepositoryTest {
                 .followerId(corinne.getId())
                 .followingId(mincho.getId())
                 .build());
-        Member updateMember = Member.builder()
-                .followerCount(mincho.getFollowerCount() + 1)
-                .build();
-        mincho.update(updateMember);
+        mincho.follow();
         entityManager.flush();
         entityManager.clear();
 
@@ -176,9 +173,7 @@ class MemberRepositoryTest {
                 .followerId(corinne.getId())
                 .followingId(mincho.getId())
                 .build());
-        mincho.update(Member.builder()
-                .followerCount(mincho.getFollowerCount() + 1)
-                .build());
+        mincho.follow();
         entityManager.flush();
         entityManager.clear();
 
@@ -216,9 +211,7 @@ class MemberRepositoryTest {
                 .followerId(corinne.getId())
                 .followingId(mincho.getId())
                 .build());
-        mincho.update(Member.builder()
-                .followerCount(mincho.getFollowerCount() + 1)
-                .build());
+        mincho.follow();
         entityManager.flush();
         entityManager.clear();
 
@@ -256,10 +249,7 @@ class MemberRepositoryTest {
                 .followerId(corinne.getId())
                 .followingId(mincho.getId())
                 .build());
-        Member updateMember = Member.builder()
-                .followerCount(mincho.getFollowerCount() + 1)
-                .build();
-        mincho.update(updateMember);
+        mincho.follow();
         entityManager.flush();
         entityManager.clear();
 

backend/src/test/java/com/woowacourse/f12/domain/member/MemberTest.java

@@ -1,8 +1,10 @@
 package com.woowacourse.f12.domain.member;
 
+import com.woowacourse.f12.exception.badrequest.InvalidFollowerCountException;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 class MemberTest {
 
@@ -55,4 +57,74 @@ class MemberTest {
         assertThat(member).usingRecursiveComparison()
                 .isEqualTo(expected);
     }
+
+    @Test
+    void 팔로워_수를_증가한다() {
+        // given
+        Member member = Member.builder()
+                .id(1L)
+                .name("유현지")
+                .imageUrl("imageUrl")
+                .careerLevel(CareerLevel.SENIOR)
+                .jobType(JobType.BACKEND)
+                .build();
+        Member expected = Member.builder()
+                .id(1L)
+                .name("유현지")
+                .imageUrl("imageUrl")
+                .careerLevel(CareerLevel.SENIOR)
+                .jobType(JobType.BACKEND)
+                .followerCount(1)
+                .build();
+
+        // when
+        member.follow();
+
+        // then
+        assertThat(member).usingRecursiveComparison()
+                .isEqualTo(expected);
+    }
+
+    @Test
+    void 팔로워_수를_감소한다() {
+        // given
+        Member member = Member.builder()
+                .id(1L)
+                .name("유현지")
+                .imageUrl("imageUrl")
+                .careerLevel(CareerLevel.SENIOR)
+                .jobType(JobType.BACKEND)
+                .followerCount(1)
+                .build();
+        Member expected = Member.builder()
+                .id(1L)
+                .name("유현지")
+                .imageUrl("imageUrl")
+                .careerLevel(CareerLevel.SENIOR)
+                .jobType(JobType.BACKEND)
+                .build();
+
+        // when
+        member.unfollow();
+
+        // then
+        assertThat(member).usingRecursiveComparison()
+                .isEqualTo(expected);
+    }
+
+    @Test
+    void 팔로워_수가_0인_상태에서_팔로워_수를_감소하면_예외가_발생한다() {
+        // given
+        Member member = Member.builder()
+                .id(1L)
+                .name("유현지")
+                .imageUrl("imageUrl")
+                .careerLevel(CareerLevel.SENIOR)
+                .jobType(JobType.BACKEND)
+                .build();
+
+        // when, then
+        assertThatThrownBy(member::unfollow)
+                .isInstanceOf(InvalidFollowerCountException.class);
+    }
 }