[WALWAL-159] 피드 작업 (#104)

* [WALWAL-159] 피드 작업

* fix: 약간 수정

* fix: resolve review

* fix: 테스트 케이스 앞에 public 삭제

src/main/java/com/depromeet/stonebed/domain/feed/api/FeedController.java

@@ -0,0 +1,23 @@
+package com.depromeet.stonebed.domain.feed.api;
+
+import com.depromeet.stonebed.domain.feed.application.FeedService;
+import com.depromeet.stonebed.domain.feed.dto.request.FeedGetRequest;
+import com.depromeet.stonebed.domain.feed.dto.response.FeedGetResponse;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+@Tag(name = "7. [피드]", description = "피드 관련 API입니다.")
+@RestController
+@RequestMapping("/feed")
+@RequiredArgsConstructor
+public class FeedController {
+    private final FeedService feedService;
+
+    @GetMapping
+    public FeedGetResponse getFeed(
+            @RequestParam(required = false) String cursor, @RequestParam int limit) {
+        FeedGetRequest request = new FeedGetRequest(cursor, limit);
+        return feedService.getFeed(request);
+    }
+}

src/main/java/com/depromeet/stonebed/domain/feed/application/FeedService.java

@@ -0,0 +1,54 @@
+package com.depromeet.stonebed.domain.feed.application;
+
+import com.depromeet.stonebed.domain.feed.dao.FeedRepository;
+import com.depromeet.stonebed.domain.feed.dto.request.FeedGetRequest;
+import com.depromeet.stonebed.domain.feed.dto.response.FeedContentGetResponse;
+import com.depromeet.stonebed.domain.feed.dto.response.FeedGetResponse;
+import com.depromeet.stonebed.domain.member.domain.Member;
+import com.depromeet.stonebed.domain.missionRecord.domain.MissionRecord;
+import com.depromeet.stonebed.global.util.MemberUtil;
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@Transactional
+@RequiredArgsConstructor
+public class FeedService {
+    private final FeedRepository feedRepository;
+    private final MemberUtil memberUtil;
+
+    @Transactional(readOnly = true)
+    public FeedGetResponse getFeed(FeedGetRequest request) {
+        Member currentMember = memberUtil.getCurrentMember();
+
+        List<MissionRecord> missionRecords =
+                getMissionRecords(request.cursor(), currentMember.getId(), request.limit());
+
+        List<FeedContentGetResponse> feedContentList =
+                missionRecords.stream().map(FeedContentGetResponse::from).toList();
+
+        String nextCursor = getNextCursor(missionRecords, request.limit());
+
+        return FeedGetResponse.from(feedContentList, nextCursor);
+    }
+
+    private String getNextCursor(List<MissionRecord> records, int limit) {
+        if (records.size() < limit) {
+            return null;
+        }
+
+        MissionRecord lastRecord = records.get(records.size() - 1);
+        Long lastId = lastRecord.getId();
+        return String.valueOf(lastId);
+    }
+
+    private List<MissionRecord> getMissionRecords(String cursor, Long memberId, int limit) {
+        if (cursor == null || cursor.isEmpty()) {
+            return feedRepository.getFeedContents(memberId, limit);
+        }
+
+        return feedRepository.getFeedContentsUsingCursor(Long.parseLong(cursor), memberId, limit);
+    }
+}

src/main/java/com/depromeet/stonebed/domain/feed/dao/FeedRepository.java

@@ -0,0 +1,6 @@
+package com.depromeet.stonebed.domain.feed.dao;
+
+import com.depromeet.stonebed.domain.missionRecord.domain.MissionRecord;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface FeedRepository extends JpaRepository<MissionRecord, Long>, FeedRepositoryCustom {}

src/main/java/com/depromeet/stonebed/domain/feed/dao/FeedRepositoryCustom.java

@@ -0,0 +1,10 @@
+package com.depromeet.stonebed.domain.feed.dao;
+
+import com.depromeet.stonebed.domain.missionRecord.domain.MissionRecord;
+import java.util.List;
+
+public interface FeedRepositoryCustom {
+    List<MissionRecord> getFeedContentsUsingCursor(Long missionRecordId, Long memberId, int limit);
+
+    List<MissionRecord> getFeedContents(Long memberId, int limit);
+}

src/main/java/com/depromeet/stonebed/domain/feed/dao/FeedRepositoryImpl.java

@@ -0,0 +1,42 @@
+package com.depromeet.stonebed.domain.feed.dao;
+
+import static com.depromeet.stonebed.domain.missionRecord.domain.QMissionRecord.missionRecord;
+
+import com.depromeet.stonebed.domain.missionRecord.domain.MissionRecord;
+import com.querydsl.jpa.impl.JPAQueryFactory;
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Repository;
+
+@Repository
+@RequiredArgsConstructor
+public class FeedRepositoryImpl implements FeedRepositoryCustom {
+    private final JPAQueryFactory queryFactory;
+
+    @Override
+    public List<MissionRecord> getFeedContentsUsingCursor(
+            Long missionRecordId, Long memberId, int limit) {
+        return queryFactory
+                .select(missionRecord)
+                .from(missionRecord)
+                .where(
+                        missionRecord
+                                .id
+                                .lt(missionRecordId)
+                                .and(missionRecord.member.id.eq(memberId)))
+                .orderBy(missionRecord.id.desc())
+                .limit(limit)
+                .fetch();
+    }
+
+    @Override
+    public List<MissionRecord> getFeedContents(Long memberId, int limit) {
+        return queryFactory
+                .select(missionRecord)
+                .from(missionRecord)
+                .where(missionRecord.member.id.eq(memberId))
+                .orderBy(missionRecord.id.desc())
+                .limit(limit)
+                .fetch();
+    }
+}

src/main/java/com/depromeet/stonebed/domain/feed/dto/request/FeedGetRequest.java

@@ -0,0 +1,7 @@
+package com.depromeet.stonebed.domain.feed.dto.request;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+public record FeedGetRequest(
+        @Schema(description = "커서 위치", example = "1") String cursor,
+        @Schema(description = "피드 당 항목 수", example = "5") int limit) {}

src/main/java/com/depromeet/stonebed/domain/feed/dto/response/FeedContentGetResponse.java

@@ -0,0 +1,20 @@
+package com.depromeet.stonebed.domain.feed.dto.response;
+
+import com.depromeet.stonebed.domain.missionRecord.domain.MissionRecord;
+import io.swagger.v3.oas.annotations.media.Schema;
+import java.time.LocalDate;
+
+public record FeedContentGetResponse(
+        @Schema(description = "미션 ID", example = "1") Long missionId,
+        @Schema(description = "작성자 ID", example = "1") Long authorId,
+        @Schema(description = "미션 기록 이미지 URL", example = "example.jpeg")
+                String missionRecordImageUrl,
+        @Schema(description = "미션 기록 생성일") LocalDate createdDate) {
+    public static FeedContentGetResponse from(MissionRecord missionRecord) {
+        return new FeedContentGetResponse(
+                missionRecord.getId(),
+                missionRecord.getMember().getId(),
+                missionRecord.getImageUrl(),
+                missionRecord.getCreatedAt().toLocalDate());
+    }
+}

src/main/java/com/depromeet/stonebed/domain/feed/dto/response/FeedGetResponse.java

@@ -0,0 +1,12 @@
+package com.depromeet.stonebed.domain.feed.dto.response;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+import java.util.List;
+
+public record FeedGetResponse(
+        List<FeedContentGetResponse> list,
+        @Schema(description = "커서 위치", example = "1") String nextCursor) {
+    public static FeedGetResponse from(List<FeedContentGetResponse> list, String nextCursor) {
+        return new FeedGetResponse(list, nextCursor);
+    }
+}

src/test/java/com/depromeet/stonebed/domain/feed/application/FeedServiceTest.java

@@ -0,0 +1,117 @@
+package com.depromeet.stonebed.domain.feed.application;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.*;
+
+import com.depromeet.stonebed.domain.feed.dao.FeedRepository;
+import com.depromeet.stonebed.domain.feed.dto.request.FeedGetRequest;
+import com.depromeet.stonebed.domain.feed.dto.response.FeedGetResponse;
+import com.depromeet.stonebed.domain.member.domain.Member;
+import com.depromeet.stonebed.domain.missionRecord.domain.MissionRecord;
+import com.depromeet.stonebed.global.util.MemberUtil;
+import com.navercorp.fixturemonkey.FixtureMonkey;
+import com.navercorp.fixturemonkey.api.introspector.FieldReflectionArbitraryIntrospector;
+import java.util.ArrayList;
+import java.util.List;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+public class FeedServiceTest {
+    @Mock private FeedRepository feedRepository;
+
+    @Mock private MemberUtil memberUtil;
+
+    @InjectMocks private FeedService feedService;
+
+    private FixtureMonkey fixtureMonkey;
+
+    @BeforeEach
+    void setUp() {
+        fixtureMonkey =
+                FixtureMonkey.builder()
+                        .objectIntrospector(FieldReflectionArbitraryIntrospector.INSTANCE)
+                        .defaultNotNull(true)
+                        .build();
+        MockitoAnnotations.openMocks(this);
+    }
+
+    @Test
+    void 피드_조회_성공() {
+        // Given
+        Member member = fixtureMonkey.giveMeOne(Member.class);
+        List<MissionRecord> missionRecords = new ArrayList<>();
+
+        for (int i = 0; i < 5; i++) {
+            missionRecords.add(fixtureMonkey.giveMeOne(MissionRecord.class));
+        }
+
+        when(memberUtil.getCurrentMember()).thenReturn(member);
+        when(feedRepository.getFeedContents(member.getId(), 5)).thenReturn(missionRecords);
+
+        // When
+        FeedGetResponse feedGetResponse = feedService.getFeed(new FeedGetRequest(null, 5));
+
+        // Then
+        assertThat(feedGetResponse.list().size()).isEqualTo(5);
+        String nextCursor = missionRecords.get(missionRecords.size() - 1).getId().toString();
+        assertThat(feedGetResponse.nextCursor()).isEqualTo(nextCursor);
+        verify(memberUtil).getCurrentMember();
+        verify(feedRepository).getFeedContents(member.getId(), 5);
+    }
+
+    @Test
+    void 피드_조회_커서_사용_성공() {
+        // Given
+        Member member = fixtureMonkey.giveMeOne(Member.class);
+        List<MissionRecord> missionRecords = new ArrayList<>();
+        String cursor = "5";
+
+        for (int i = 0; i < 5; i++) {
+            missionRecords.add(fixtureMonkey.giveMeOne(MissionRecord.class));
+        }
+
+        when(memberUtil.getCurrentMember()).thenReturn(member);
+        when(feedRepository.getFeedContentsUsingCursor(Long.parseLong(cursor), member.getId(), 5))
+                .thenReturn(missionRecords);
+
+        // When
+        FeedGetResponse feedGetResponse = feedService.getFeed(new FeedGetRequest(cursor, 5));
+
+        // Then
+        assertThat(feedGetResponse.list().size()).isEqualTo(5);
+        String nextCursor = missionRecords.get(missionRecords.size() - 1).getId().toString();
+        assertThat(feedGetResponse.nextCursor()).isEqualTo(nextCursor);
+        verify(memberUtil).getCurrentMember();
+        verify(feedRepository)
+                .getFeedContentsUsingCursor(Long.parseLong(cursor), member.getId(), 5);
+    }
+
+    @Test
+    void 피드_조회_커서_사용_마지막_성공() {
+        // Given
+        Member member = fixtureMonkey.giveMeOne(Member.class);
+        List<MissionRecord> missionRecords = new ArrayList<>();
+        String cursor = "5";
+
+        for (int i = 0; i < 3; i++) {
+            missionRecords.add(fixtureMonkey.giveMeOne(MissionRecord.class));
+        }
+
+        when(memberUtil.getCurrentMember()).thenReturn(member);
+        when(feedRepository.getFeedContentsUsingCursor(Long.parseLong(cursor), member.getId(), 5))
+                .thenReturn(missionRecords);
+
+        // When
+        FeedGetResponse feedGetResponse = feedService.getFeed(new FeedGetRequest(cursor, 5));
+
+        // Then
+        assertThat(feedGetResponse.list().size()).isEqualTo(3);
+        assertThat(feedGetResponse.nextCursor()).isEqualTo(null);
+        verify(memberUtil).getCurrentMember();
+        verify(feedRepository)
+                .getFeedContentsUsingCursor(Long.parseLong(cursor), member.getId(), 5);
+    }
+}