참여자 닉네임 생성, 모임의 참여자 조회 기능 생성

backend/src/main/java/mouda/backend/member/domain/Member.java

@@ -0,0 +1,36 @@
+package mouda.backend.member.domain;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import mouda.backend.moim.domain.Moim;
+
+@Entity
+@Getter
+@NoArgsConstructor
+public class Member {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	private String nickname;
+
+	@ManyToOne(fetch = FetchType.LAZY)
+	private Moim moim;
+
+	@Builder
+	public Member(String nickname) {
+		this.nickname = nickname;
+	}
+
+	public void joinMoim(Moim moim) {
+		this.moim = moim;
+	}
+}

backend/src/main/java/mouda/backend/member/repository/MemberRepository.java

@@ -0,0 +1,12 @@
+package mouda.backend.member.repository;
+
+import java.util.List;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import mouda.backend.member.domain.Member;
+
+public interface MemberRepository extends JpaRepository<Member, Long> {
+
+	List<Member> findAllByMoimId(long moimId);
+}

backend/src/main/java/mouda/backend/moim/domain/Moim.java

@@ -32,8 +32,6 @@ public class Moim {
 
 	private String place;
 
-	private int currentPeople;
-
 	private int maxPeople;
 
 	private String authorNickname;
@@ -54,16 +52,14 @@ public Moim(
 		this.date = date;
 		this.time = time;
 		this.place = place;
-		this.currentPeople = 1;
 		this.maxPeople = maxPeople;
 		this.authorNickname = authorNickname;
 		this.description = description;
 	}
 
-	public void join() {
+	public void validateAlreadyFullMoim(int currentPeople) {
 		if (currentPeople + 1 > maxPeople) {
 			throw new MoimException(HttpStatus.BAD_REQUEST, MoimErrorMessage.MAX_PEOPLE);
 		}
-		currentPeople++;
 	}
 }

backend/src/main/java/mouda/backend/moim/dto/request/MoimJoinRequest.java

@@ -1,6 +1,7 @@
 package mouda.backend.moim.dto.request;
 
 public record MoimJoinRequest(
-	Long moimId
+	Long moimId,
+	String nickname
 ) {
 }

backend/src/main/java/mouda/backend/moim/dto/response/MoimDetailsFindResponse.java

@@ -2,6 +2,7 @@
 
 import java.time.LocalDate;
 import java.time.LocalTime;
+import java.util.List;
 
 import lombok.Builder;
 import mouda.backend.moim.domain.Moim;
@@ -15,19 +16,21 @@ public record MoimDetailsFindResponse(
 	int currentPeople,
 	int maxPeople,
 	String authorNickname,
-	String description
+	String description,
+	List<String> participants
 ) {
 
-	public static MoimDetailsFindResponse toResponse(Moim moim) {
+	public static MoimDetailsFindResponse toResponse(Moim moim, List<String> participants) {
 		return MoimDetailsFindResponse.builder()
 			.title(moim.getTitle())
 			.date(moim.getDate())
 			.time(moim.getTime())
 			.place(moim.getPlace())
-			.currentPeople(moim.getCurrentPeople())
+			.currentPeople(participants.size())
 			.maxPeople(moim.getMaxPeople())
 			.authorNickname(moim.getAuthorNickname())
 			.description(moim.getDescription())
+			.participants(participants)
 			.build();
 	}
 }

backend/src/main/java/mouda/backend/moim/dto/response/MoimFindAllResponse.java

@@ -19,14 +19,14 @@ public record MoimFindAllResponse(
 	String description
 ) {
 
-	public static MoimFindAllResponse toResponse(Moim moim) {
+	public static MoimFindAllResponse toResponse(Moim moim, int currentPeople) {
 		return MoimFindAllResponse.builder()
 			.moimId(moim.getId())
 			.title(moim.getTitle())
 			.date(moim.getDate())
 			.time(moim.getTime())
 			.place(moim.getPlace())
-			.currentPeople(moim.getCurrentPeople())
+			.currentPeople(currentPeople)
 			.maxPeople(moim.getMaxPeople())
 			.authorNickname(moim.getAuthorNickname())
 			.description(moim.getDescription())

backend/src/main/java/mouda/backend/moim/service/MoimService.java

@@ -7,6 +7,8 @@
 import org.springframework.transaction.annotation.Transactional;
 
 import lombok.RequiredArgsConstructor;
+import mouda.backend.member.domain.Member;
+import mouda.backend.member.repository.MemberRepository;
 import mouda.backend.moim.domain.Moim;
 import mouda.backend.moim.dto.request.MoimCreateRequest;
 import mouda.backend.moim.dto.request.MoimJoinRequest;
@@ -24,16 +26,26 @@ public class MoimService {
 
 	private final MoimRepository moimRepository;
 
+	private final MemberRepository memberRepository;
+
 	public Moim createMoim(MoimCreateRequest moimCreateRequest) {
-		return moimRepository.save(moimCreateRequest.toEntity());
+		Member author = new Member(moimCreateRequest.authorNickname());
+		Moim moim = moimRepository.save(moimCreateRequest.toEntity());
+		author.joinMoim(moim);
+		memberRepository.save(author);
+
+		return moim;
 	}
 
 	@Transactional(readOnly = true)
 	public MoimFindAllResponses findAllMoim() {
 		List<Moim> moims = moimRepository.findAll();
 		return new MoimFindAllResponses(
 			moims.stream()
-				.map(MoimFindAllResponse::toResponse)
+				.map(moim -> {
+					List<Member> participants = memberRepository.findAllByMoimId(moim.getId());
+					return MoimFindAllResponse.toResponse(moim, participants.size());
+				})
 				.toList()
 		);
 	}
@@ -43,18 +55,32 @@ public MoimDetailsFindResponse findMoimDetails(long id) {
 		Moim moim = moimRepository.findById(id)
 			.orElseThrow(() -> new MoimException(HttpStatus.NOT_FOUND, MoimErrorMessage.NOT_FOUND));
 
-		return MoimDetailsFindResponse.toResponse(moim);
+		List<String> participants = memberRepository.findAllByMoimId(id).stream()
+			.map(Member::getNickname)
+			.toList();
+
+		return MoimDetailsFindResponse.toResponse(moim, participants);
 	}
 
 	public void joinMoim(MoimJoinRequest moimJoinRequest) {
+		Member member = new Member(moimJoinRequest.nickname());
 		Moim moim = moimRepository.findById(moimJoinRequest.moimId())
 			.orElseThrow(() -> new MoimException(HttpStatus.NOT_FOUND, MoimErrorMessage.NOT_FOUND));
-		moim.join();
+
+		member.joinMoim(moim);
+		memberRepository.save(member);
+		List<Member> participants = memberRepository.findAllByMoimId(moim.getId());
+
+		moim.validateAlreadyFullMoim(participants.size());
 	}
 
 	public void deleteMoim(long id) {
 		Moim moim = moimRepository.findById(id)
 			.orElseThrow(() -> new MoimException(HttpStatus.NOT_FOUND, MoimErrorMessage.NOT_FOUND));
+		List<Member> participants = memberRepository.findAllByMoimId(moim.getId());
+		for (Member participant : participants) {
+			memberRepository.deleteById(participant.getId());
+		}
 
 		moimRepository.delete(moim);
 	}

backend/src/test/java/mouda/backend/config/DatabaseCleaner.java

@@ -1,26 +1,29 @@
 package mouda.backend.config;
 
-import java.util.List;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+import jakarta.persistence.EntityManager;
 
 @Component
 public class DatabaseCleaner {
 
-    @Autowired
-    private JdbcTemplate jdbcTemplate;
-
-    public DatabaseCleaner(final JdbcTemplate jdbcTemplate) {
-        this.jdbcTemplate = jdbcTemplate;
-    }
-
-    public void cleanUp() {
-        String sql = "SELECT table_name FROM information_schema.tables WHERE table_schema = 'PUBLIC' AND table_type='BASE TABLE'";
-        List<String> tables = jdbcTemplate.queryForList(sql, String.class);
-        for (String tableName : tables) {
-            jdbcTemplate.update("DELETE FROM " + tableName);
-            jdbcTemplate.update("ALTER TABLE " + tableName + " alter column id restart with 1");
-        }
-    }
+	@Autowired
+	private EntityManager entityManager;
+
+	public DatabaseCleaner(EntityManager entityManager) {
+		this.entityManager = entityManager;
+	}
+
+	@Transactional
+	public void cleanUp() {
+		entityManager.createNativeQuery("DELETE FROM MEMBER").executeUpdate();
+		entityManager.createNativeQuery("ALTER TABLE MEMBER alter column id restart with 1").executeUpdate();
+
+		entityManager.createNativeQuery("DELETE FROM MOIM").executeUpdate();
+		entityManager.createNativeQuery("ALTER TABLE MOIM alter column id restart with 1").executeUpdate();
+
+		entityManager.clear();
+	}
 }

backend/src/test/java/mouda/backend/member/repository/MemberRepositoryTest.java

@@ -0,0 +1,48 @@
+package mouda.backend.member.repository;
+
+import java.util.List;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+import mouda.backend.config.DatabaseCleaner;
+import mouda.backend.member.domain.Member;
+import mouda.backend.moim.domain.Moim;
+import mouda.backend.moim.repository.MoimRepository;
+
+@SpringBootTest
+class MemberRepositoryTest {
+
+	@Autowired
+	private MemberRepository memberRepository;
+
+	@Autowired
+	private MoimRepository moimRepository;
+
+	@Autowired
+	private DatabaseCleaner databaseCleaner;
+
+	@AfterEach
+	void cleanUp() {
+		databaseCleaner.cleanUp();
+	}
+
+	@DisplayName("모임에 가입된 참여자의 수를 반환한다.")
+	@Test
+	void findNickNamesByMoimId() {
+		Member member = new Member("tehah");
+		Moim moim = Moim.builder()
+			.build();
+		Moim saveMoim = moimRepository.save(moim);
+		member.joinMoim(saveMoim);
+		memberRepository.save(member);
+
+		List<Member> participants = memberRepository.findAllByMoimId(saveMoim.getId());
+
+		Assertions.assertThat(participants.size()).isEqualTo(1);
+	}
+}

backend/src/test/java/mouda/backend/moim/service/MoimServiceTest.java

@@ -14,6 +14,8 @@
 import org.springframework.boot.test.context.SpringBootTest;
 
 import mouda.backend.config.DatabaseCleaner;
+import mouda.backend.member.domain.Member;
+import mouda.backend.member.repository.MemberRepository;
 import mouda.backend.moim.domain.Moim;
 import mouda.backend.moim.dto.request.MoimCreateRequest;
 import mouda.backend.moim.dto.request.MoimJoinRequest;
@@ -30,6 +32,9 @@ class MoimServiceTest {
 	@Autowired
 	private MoimRepository moimRepository;
 
+	@Autowired
+	private MemberRepository memberRepository;
+
 	@Autowired
 	private DatabaseCleaner databaseCleaner;
 
@@ -87,14 +92,15 @@ void joinMoim() {
 			"title", LocalDate.now(), LocalTime.now(), "place",
 			10, "안나", "설명"
 		);
-		moimService.createMoim(moimCreateRequest);
+		Moim moim = moimService.createMoim(moimCreateRequest);
 
-		MoimJoinRequest moimJoinRequest = new MoimJoinRequest(1L);
+		MoimJoinRequest moimJoinRequest = new MoimJoinRequest(moim.getId(), "호기");
 		moimService.joinMoim(moimJoinRequest);
+		List<Member> participants = memberRepository.findAllByMoimId(moim.getId());
 
-		Optional<Moim> moimOptional = moimRepository.findById(1L);
+		Optional<Moim> moimOptional = moimRepository.findById(moim.getId());
 		assertThat(moimOptional).isNotEmpty();
-		assertThat(moimOptional.get().getCurrentPeople()).isEqualTo(2);
+		assertThat(participants.size()).isEqualTo(2);
 	}
 
 	@DisplayName("모임을 삭제한다.")