feat: 좋아요 TopN 모두르이 답변 조회 기능 구현 #32

plu-api/src/main/kotlin/com/th/plu/api/controller/answer/AnswerController.kt

@@ -6,7 +6,7 @@ import com.th.plu.api.controller.answer.dto.response.AnswerInfoResponse
 import com.th.plu.api.controller.answer.dto.response.EveryAnswerInfoResponse
 import com.th.plu.api.service.answer.AnswerService
 import com.th.plu.common.dto.response.ApiResponse
-import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrievePageResponses
+import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrieveResponses
 import io.swagger.v3.oas.annotations.Operation
 import io.swagger.v3.oas.annotations.tags.Tag
 import org.springframework.web.bind.annotation.*
@@ -49,12 +49,21 @@ class AnswerController(
     }
 
     @Auth
-    @Operation(summary = "[인증] 모두의 답변 조회")
+    @Operation(summary = "[인증] 모두의 답변 조회(무한 스크롤)")
     @GetMapping("/v1/answers")
     fun paginateAnswersByCursor(
             @RequestParam(defaultValue = Long.MAX_VALUE.toString()) lastAnswerId: Long,
             @RequestParam(defaultValue = "10") pageSize: Long,
-    ): ApiResponse<EveryAnswerRetrievePageResponses> {
-        return ApiResponse.success(answerService.retrieveEveryAnswersWithCursor(lastAnswerId, pageSize))
+    ): ApiResponse<EveryAnswerRetrieveResponses> {
+        return ApiResponse.success(answerService.findEveryAnswersWithCursor(lastAnswerId, pageSize))
+    }
+
+    @Auth
+    @Operation(summary = "[인증] 모두의 답변 조회(좋아요 TopN)")
+    @GetMapping("/v1/answers/popular")
+    fun getAnswersAboutLikeTopN(
+            @RequestParam(defaultValue = "10") getCount: Long,
+    ): ApiResponse<EveryAnswerRetrieveResponses> {
+        return ApiResponse.success(answerService.findEveryAnswersLikeTopN(getCount))
     }
 }

plu-api/src/main/kotlin/com/th/plu/api/service/answer/AnswerService.kt

@@ -3,7 +3,7 @@ package com.th.plu.api.service.answer
 import com.th.plu.api.controller.answer.dto.response.AnswerInfoResponse
 import com.th.plu.api.controller.answer.dto.response.EveryAnswerInfoResponse
 import com.th.plu.api.service.like.LikeValidator
-import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrievePageResponses
+import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrieveResponses
 import com.th.plu.domain.domain.answer.explorer.AnswerExplorer
 import com.th.plu.domain.domain.answer.explorer.QuestionExplorer
 import com.th.plu.domain.domain.answer.repository.AnswerRepository
@@ -55,17 +55,24 @@ class AnswerService(
     }
 
     @Transactional(readOnly = true)
-    fun retrieveEveryAnswersWithCursor(lastAnswerId: Long, pageSize: Long): EveryAnswerRetrievePageResponses {
+    fun findEveryAnswersWithCursor(lastAnswerId: Long, pageSize: Long): EveryAnswerRetrieveResponses {
         val todayQuestionId = questionExplorer.findTodayQuestion().id
-        val answerInfos = answerRepository.findEveryAnswersWithCursorAndPageSize(todayQuestionId!!, lastAnswerId, pageSize)
-        return EveryAnswerRetrievePageResponses(answerInfos)
+        val answers = answerRepository.findEveryAnswersWithCursorAndPageSize(todayQuestionId!!, lastAnswerId, pageSize)
+        return EveryAnswerRetrieveResponses(answers)
     }
 
     @Transactional(readOnly = true)
     fun findEveryAnswerInfo(): EveryAnswerInfoResponse {
         val todayQuestion = questionExplorer.findTodayQuestion()
-        val answerCount = answerRepository.findPublicAnswerCountByQuestionId(todayQuestion.id!!)
+        val answerCount = answerRepository.findPublicAnswersCountByQuestionId(todayQuestion.id!!)
 
         return EveryAnswerInfoResponse.of(todayQuestion, answerCount)
     }
+
+    fun findEveryAnswersLikeTopN(getCount: Long): EveryAnswerRetrieveResponses {
+        val todayQuestion = questionExplorer.findTodayQuestion()
+        val answers = answerRepository.findPublicAnswersLikeTopN(todayQuestion.id!!, getCount)
+
+        return EveryAnswerRetrieveResponses(answers)
+    }
 }

plu-domain/src/main/kotlin/com/th/plu/domain/domain/answer/dto/EveryAnswerRetrievePageResponse.kt → plu-domain/src/main/kotlin/com/th/plu/domain/domain/answer/dto/EveryAnswerRetrieveResponse.kt

@@ -2,8 +2,8 @@ package com.th.plu.domain.domain.answer.dto
 
 import com.querydsl.core.annotations.QueryProjection
 
-data class EveryAnswerRetrievePageResponse @QueryProjection constructor(
+data class EveryAnswerRetrieveResponse @QueryProjection constructor(
         val answerId: Long,
         val likeCount: Long,
         val answerContent: String
-)
+)

plu-domain/src/main/kotlin/com/th/plu/domain/domain/answer/dto/EveryAnswerRetrieveResponses.kt

@@ -0,0 +1,3 @@
+package com.th.plu.domain.domain.answer.dto
+
+data class EveryAnswerRetrieveResponses(val answerInfos: List<EveryAnswerRetrieveResponse>)

plu-domain/src/main/kotlin/com/th/plu/domain/domain/answer/repository/AnswerRepositoryCustom.kt

@@ -1,12 +1,14 @@
 package com.th.plu.domain.domain.answer.repository
 
 import com.th.plu.domain.domain.answer.Answer
-import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrievePageResponse
+import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrieveResponse
 
 interface AnswerRepositoryCustom {
     fun findAnswerById(id: Long): Answer?
 
-    fun findEveryAnswersWithCursorAndPageSize(questionId: Long, lastAnswerId: Long, pageSize: Long): List<EveryAnswerRetrievePageResponse>
+    fun findEveryAnswersWithCursorAndPageSize(questionId: Long, lastAnswerId: Long, pageSize: Long): List<EveryAnswerRetrieveResponse>
 
-    fun findPublicAnswerCountByQuestionId(questionId: Long): Long
+    fun findPublicAnswersCountByQuestionId(questionId: Long): Long
+
+    fun findPublicAnswersLikeTopN(questionId: Long, getCount: Long): List<EveryAnswerRetrieveResponse>
 }

plu-domain/src/main/kotlin/com/th/plu/domain/domain/answer/repository/AnswerRepositoryImpl.kt

@@ -3,8 +3,8 @@ package com.th.plu.domain.domain.answer.repository
 import com.querydsl.jpa.impl.JPAQueryFactory
 import com.th.plu.domain.domain.answer.Answer
 import com.th.plu.domain.domain.answer.QAnswer.answer
-import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrievePageResponse
-import com.th.plu.domain.domain.answer.dto.QEveryAnswerRetrievePageResponse
+import com.th.plu.domain.domain.answer.dto.EveryAnswerRetrieveResponse
+import com.th.plu.domain.domain.answer.dto.QEveryAnswerRetrieveResponse
 import com.th.plu.domain.domain.like.QLike.like
 import org.springframework.stereotype.Repository
 
@@ -18,9 +18,9 @@ class AnswerRepositoryImpl(private val queryFactory: JPAQueryFactory) : AnswerRe
                 .fetchOne()
     }
 
-    override fun findEveryAnswersWithCursorAndPageSize(questionId: Long, lastAnswerId: Long, pageSize: Long): List<EveryAnswerRetrievePageResponse> {
+    override fun findEveryAnswersWithCursorAndPageSize(questionId: Long, lastAnswerId: Long, pageSize: Long): List<EveryAnswerRetrieveResponse> {
         return queryFactory
-                .select(QEveryAnswerRetrievePageResponse(answer.id, like.answer.id.count(), answer.content))
+                .select(QEveryAnswerRetrieveResponse(answer.id, like.answer.id.count(), answer.content))
                 .from(answer)
                 .leftJoin(like).on(like.answer.id.eq(answer.id))
                 .where(
@@ -34,11 +34,26 @@ class AnswerRepositoryImpl(private val queryFactory: JPAQueryFactory) : AnswerRe
                 .fetch()
     }
 
-    override fun findPublicAnswerCountByQuestionId(questionId: Long): Long {
+    override fun findPublicAnswersCountByQuestionId(questionId: Long): Long {
         return queryFactory
                 .select(answer.id.count())
                 .from(answer)
                 .where(answer.question.id.eq(questionId))
                 .fetchOne()!!
     }
+
+    override fun findPublicAnswersLikeTopN(questionId: Long, getCount: Long): List<EveryAnswerRetrieveResponse> {
+        return queryFactory
+                .select(QEveryAnswerRetrieveResponse(answer.id, like.answer.id.count(), answer.content))
+                .from(answer)
+                .leftJoin(like).on(like.answer.id.eq(answer.id))
+                .where(
+                        answer.isPublic.eq(true),
+                        answer.question.id.eq(questionId)
+                )
+                .groupBy(answer.id)
+                .orderBy(like.answer.id.count().desc())
+                .limit(getCount)
+                .fetch()
+    }
 }