♻️ 서킷 브레이커 패턴으로 외부 API 장애 관리 (#206) (#207)

* ➕ 서킷 브레이커 관련 의존성 추가 (#206)

* ✨ 서킷 브레이커 관련 환경 설정 추가 (#206)

* ✨ 외부 API, Redis 캐시에 서킷 브레이커 도입 (#206)

* ♻️ 유실물 오프셋 기반으로 다시 변경 (#181)

* 🔧 설정 파일 업데이트 (#206)

* 🐛 컨트롤러 테스트 오류 수정 (#206)

ahachul_backend/build.gradle.kts

@@ -86,6 +86,11 @@ dependencies {
     implementation("org.jetbrains.kotlin:kotlin-reflect")
     runtimeOnly("com.mysql:mysql-connector-j")
     testImplementation("org.springframework.boot:spring-boot-starter-test")
+
+    // https://mvnrepository.com/artifact/io.github.resilience4j/resilience4j-spring-boot3
+    implementation("io.github.resilience4j:resilience4j-spring-boot3:2.0.2")
+    implementation("org.springframework.boot:spring-boot-starter-actuator")
+    implementation("org.springframework.boot:spring-boot-starter-aop")
 }
 
 tasks.withType<KotlinCompile> {

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/community/adapter/web/in/CommunityPostController.kt

@@ -6,19 +6,14 @@ import backend.team.ahachul_backend.api.community.application.port.`in`.Communit
 import backend.team.ahachul_backend.common.annotation.Authentication
 import backend.team.ahachul_backend.common.response.CommonResponse
 import org.springframework.data.domain.Pageable
-import org.springframework.web.bind.annotation.DeleteMapping
-import org.springframework.web.bind.annotation.GetMapping
-import org.springframework.web.bind.annotation.PatchMapping
-import org.springframework.web.bind.annotation.PathVariable
-import org.springframework.web.bind.annotation.PostMapping
-import org.springframework.web.bind.annotation.RequestBody
-import org.springframework.web.bind.annotation.RestController
+import org.springframework.web.bind.annotation.*
 
 @RestController
 class CommunityPostController(
     private val communityPostUseCase: CommunityPostUseCase
 ) {
 
+    @Authentication
     @GetMapping("/v1/community-posts")
     fun searchCommunityPosts(
         pageable: Pageable,
@@ -50,4 +45,4 @@ class CommunityPostController(
     fun deleteCommunityPost(@PathVariable postId: Long): CommonResponse<DeleteCommunityPostDto.Response> {
         return CommonResponse.success(communityPostUseCase.deleteCommunityPost(DeleteCommunityPostCommand(postId)))
     }
-}
+}

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/community/application/service/CommunityPostService.kt

@@ -2,20 +2,20 @@ package backend.team.ahachul_backend.api.community.application.service
 
 import backend.team.ahachul_backend.api.community.adapter.web.`in`.dto.post.*
 import backend.team.ahachul_backend.api.community.application.port.`in`.CommunityPostUseCase
-import backend.team.ahachul_backend.api.community.application.port.out.*
+import backend.team.ahachul_backend.api.community.application.port.out.CommunityPostFileReader
+import backend.team.ahachul_backend.api.community.application.port.out.CommunityPostHashTagReader
+import backend.team.ahachul_backend.api.community.application.port.out.CommunityPostReader
+import backend.team.ahachul_backend.api.community.application.port.out.CommunityPostWriter
 import backend.team.ahachul_backend.api.community.domain.entity.CommunityPostEntity
 import backend.team.ahachul_backend.api.community.domain.entity.CommunityPostFileEntity
 import backend.team.ahachul_backend.api.member.application.port.out.MemberReader
-import backend.team.ahachul_backend.api.rank.application.service.HashTagRankService
-import backend.team.ahachul_backend.api.rank.event.HashTagSearchEvent
 import backend.team.ahachul_backend.common.dto.ImageDto
+import backend.team.ahachul_backend.common.logging.NamedLogger
 import backend.team.ahachul_backend.common.persistence.SubwayLineReader
 import backend.team.ahachul_backend.common.support.ViewsSupport
 import backend.team.ahachul_backend.common.utils.RequestUtils
-import org.springframework.context.ApplicationEventPublisher
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Transactional
-import java.time.LocalDateTime
 
 @Service
 @Transactional(readOnly = true)
@@ -31,12 +31,13 @@ class CommunityPostService(
     private val communityPostHashTagService: CommunityPostHashTagService,
     private val communityPostFileService: CommunityPostFileService,
 
-    private val viewsSupport: ViewsSupport,
-    private val publisher: ApplicationEventPublisher
+    private val viewsSupport: ViewsSupport
 ): CommunityPostUseCase {
 
+    private val logger = NamedLogger("HASHTAG_LOGGER")
+
     override fun searchCommunityPosts(command: SearchCommunityPostCommand): SearchCommunityPostDto.Response {
-        val memberId = RequestUtils.getAttribute("memberId")!!
+        val userId = RequestUtils.getAttribute("memberId")!!
         val searchCommunityPosts = communityPostReader.searchCommunityPosts(command)
         val posts = searchCommunityPosts
             .map {
@@ -50,11 +51,7 @@ class CommunityPostService(
             }.toList()
 
         if (isHashTagSearchCond(command.hashTag, command.content)) {
-            val searchEvent = HashTagSearchEvent(
-                    hashTagName = command.hashTag!!,
-                    userId = memberId
-            )
-            publisher.publishEvent(searchEvent)
+            logger.info("userId = $userId hashtag = ${command.hashTag}")
         }
 
         return SearchCommunityPostDto.Response.of(

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/lost/adapter/web/in/LostPostController.kt

@@ -21,9 +21,10 @@ class LostPostController(
 
     @GetMapping("/v1/lost-posts")
     fun searchLostPosts(
+        pageable: Pageable,
         request: SearchLostPostsDto.Request
     ): CommonResponse<SearchLostPostsDto.Response> {
-        return CommonResponse.success(lostPostService.searchLostPosts(request.toCommand()))
+        return CommonResponse.success(lostPostService.searchLostPosts(request.toCommand(pageable)))
     }
 
     @Authentication

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/lost/adapter/web/in/dto/SearchLostPostsDto.kt

@@ -4,7 +4,6 @@ import backend.team.ahachul_backend.api.lost.application.service.command.`in`.Se
 import backend.team.ahachul_backend.api.lost.domain.model.LostOrigin
 import backend.team.ahachul_backend.api.lost.domain.model.LostStatus
 import backend.team.ahachul_backend.api.lost.domain.model.LostType
-import backend.team.ahachul_backend.common.dto.ImageDto
 import org.springframework.data.domain.Pageable
 
 class SearchLostPostsDto {
@@ -17,14 +16,13 @@ class SearchLostPostsDto {
         val lostPostId: Long,
         val pageSize: Int,
     ) {
-        fun toCommand(): SearchLostPostCommand {
+        fun toCommand(pageable: Pageable): SearchLostPostCommand {
             return SearchLostPostCommand(
                 lostType = lostType,
                 subwayLineId = subwayLineId,
                 lostOrigin = origin,
                 keyword = keyword,
-                lostPostId = lostPostId,
-                pageSize = pageSize
+                pageable = pageable
             )
         }
     }

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/lost/adapter/web/out/CustomLostPostRepository.kt

@@ -61,20 +61,27 @@ class CustomLostPostRepository(
     }
 
     fun searchLostPosts(command: GetSliceLostPostsCommand): Slice<LostPostEntity> {
-        val pageable = PageRequest.of(0, command.pageSize)
+        val pageable = command.pageable
         val response = queryFactory.selectFrom(lostPostEntity)
             .where(
-                ltPostId(command.lostPostId),
                 lostOriginEq(command.lostOrigin),
                 subwayLineEq(command.subwayLine),
                 lostTypeEq(command.lostType),
                 titleAndContentLike(command.keyword),
             )
             .orderBy(lostPostEntity.receivedDate.desc())
-            .limit((command.pageSize + 1).toLong())
+            .offset(getOffset(pageable).toLong())
+            .limit((pageable.pageSize + 1).toLong())
             .fetch()
 
-        return SliceImpl(response, pageable, hasNext(response, command.pageSize))
+        return SliceImpl(response, pageable, hasNext(response, pageable.pageSize))
+    }
+
+    private fun getOffset(pageable: Pageable): Int {
+        return when {
+            pageable.pageNumber != 0 -> pageable.pageNumber * pageable.pageSize
+            else -> pageable.pageNumber
+        }
     }
 
     private fun hasNext(response: MutableList<LostPostEntity>, pageSize: Int): Boolean {
@@ -111,9 +118,6 @@ class CustomLostPostRepository(
             .fetch()
     }
 
-    private fun ltPostId(postId: Long?) =
-        postId?.let { lostPostEntity.id.lt(postId) }
-
     private fun lostOriginEq(lostOrigin: LostOrigin?) =
         lostOrigin?.let { lostPostEntity.origin.eq(lostOrigin) }
 

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/lost/application/service/command/in/SearchLostPostCommand.kt

@@ -2,12 +2,12 @@ package backend.team.ahachul_backend.api.lost.application.service.command.`in`
 
 import backend.team.ahachul_backend.api.lost.domain.model.LostOrigin
 import backend.team.ahachul_backend.api.lost.domain.model.LostType
+import org.springframework.data.domain.Pageable
 
 class SearchLostPostCommand(
     val lostType: LostType,
     val lostOrigin: LostOrigin?,
     val subwayLineId: Long?,
     val keyword: String?,
-    val lostPostId: Long?,
-    val pageSize: Int
+    val pageable: Pageable
 )

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/lost/application/service/command/out/GetSliceLostPostsCommand.kt

@@ -4,14 +4,14 @@ import backend.team.ahachul_backend.api.lost.application.service.command.`in`.Se
 import backend.team.ahachul_backend.api.lost.domain.model.LostOrigin
 import backend.team.ahachul_backend.api.lost.domain.model.LostType
 import backend.team.ahachul_backend.common.domain.entity.SubwayLineEntity
+import org.springframework.data.domain.Pageable
 
 class GetSliceLostPostsCommand(
     val lostType: LostType,
     val lostOrigin: LostOrigin?,
     val subwayLine: SubwayLineEntity?,
     val keyword: String?,
-    val lostPostId: Long?,
-    val pageSize: Int
+    val pageable: Pageable
 ) {
     companion object {
         fun from(command: SearchLostPostCommand, subwayLine: SubwayLineEntity?): GetSliceLostPostsCommand {
@@ -20,8 +20,7 @@ class GetSliceLostPostsCommand(
                 lostOrigin = command.lostOrigin,
                 subwayLine = subwayLine,
                 keyword = command.keyword,
-                lostPostId = command.lostPostId,
-                pageSize = command.pageSize
+                pageable = command.pageable
             )
         }
     }

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/rank/application/service/HashTagRankService.kt

@@ -1,24 +1,31 @@
 package backend.team.ahachul_backend.api.rank.application.service
 
 import backend.team.ahachul_backend.api.rank.adapter.web.`in`.dto.GetHashTagRankDto
-import backend.team.ahachul_backend.common.constant.CommonConstant.Companion.HASHTAG_REDIS_KEY
 import backend.team.ahachul_backend.common.client.RedisClient
-import backend.team.ahachul_backend.common.logging.NamedLogger
+import backend.team.ahachul_backend.common.config.CircuitBreakerConfig.Companion.CUSTOM_CIRCUIT_BREAKER
+import backend.team.ahachul_backend.common.constant.CommonConstant
+import backend.team.ahachul_backend.common.constant.CommonConstant.Companion.HASHTAG_REDIS_KEY
+import backend.team.ahachul_backend.common.exception.CommonException
+import backend.team.ahachul_backend.common.logging.Logger
+import backend.team.ahachul_backend.common.response.ResponseCode
+import backend.team.ahachul_backend.schedule.job.RankHashTagJob
 import com.fasterxml.jackson.core.type.TypeReference
 import com.fasterxml.jackson.databind.ObjectMapper
+import io.github.resilience4j.circuitbreaker.CallNotPermittedException
+import io.github.resilience4j.circuitbreaker.annotation.CircuitBreaker
+import org.springframework.data.redis.RedisConnectionFailureException
 import org.springframework.stereotype.Service
 
 
 @Service
 class HashTagRankService(
-    val redisClient: RedisClient
+    private val redisClient: RedisClient,
+    private val rankHashTagJob: RankHashTagJob
 ){
-    val logger = NamedLogger("HASHTAG_LOGGER")
 
-    fun saveLog(name: String, userId: String) {
-        logger.info("userId = $userId hashtag = $name")
-    }
+    val logger = Logger(javaClass)
 
+    @CircuitBreaker(name = CUSTOM_CIRCUIT_BREAKER, fallbackMethod = "fallbackOnRedisCacheGet")
     fun getRank(): GetHashTagRankDto.Response {
         val mapper = ObjectMapper()
 
@@ -30,4 +37,15 @@ class HashTagRankService(
 
         return GetHashTagRankDto.Response(emptyList())
     }
+
+    fun fallbackOnRedisCacheGet(e: RedisConnectionFailureException): GetHashTagRankDto.Response {
+        logger.error("circuit breaker opened for redis hashtag cache")
+        throw CommonException(ResponseCode.FAILED_TO_CONNECT_TO_REDIS, e)
+    }
+
+    fun fallbackOnRedisCacheGet(e : CallNotPermittedException): GetHashTagRankDto.Response {
+        logger.error("circuit breaker opened for redis hashtag cache")
+        val rankList = rankHashTagJob.readHashTagLogFile(CommonConstant.HASHTAG_FILE_URL)
+        return GetHashTagRankDto.Response(rankList)
+    }
 }

ahachul_backend/src/main/kotlin/backend/team/ahachul_backend/api/train/adapter/in/TrainController.kt

@@ -6,10 +6,7 @@ import backend.team.ahachul_backend.api.train.adapter.`in`.dto.GetTrainRealTimes
 import backend.team.ahachul_backend.api.train.application.port.`in`.TrainUseCase
 import backend.team.ahachul_backend.common.annotation.Authentication
 import backend.team.ahachul_backend.common.response.CommonResponse
-import org.springframework.web.bind.annotation.GetMapping
-import org.springframework.web.bind.annotation.PathVariable
-import org.springframework.web.bind.annotation.RequestParam
-import org.springframework.web.bind.annotation.RestController
+import org.springframework.web.bind.annotation.*
 
 @RestController
 class TrainController(
@@ -21,7 +18,8 @@ class TrainController(
     fun getTrain(@PathVariable trainNo: String): CommonResponse<GetTrainDto.Response> {
         return CommonResponse.success(trainUseCase.getTrain(trainNo))
     }
-
+
+    @Authentication
     @GetMapping("/v1/trains/real-times")
     fun getTrainRealTimes(request: GetTrainRealTimesDto.Request): CommonResponse<GetTrainRealTimesDto.Response> {
         val result = trainUseCase.getTrainRealTimes(request.stationId, request.subwayLineId)