feat(ranking): 스냅샷 갱신 관측 로그를 추가한다

src/test/kotlin/kr/co/vividnext/sodalive/v2/ranking/application/CreatorRankingSnapshotRefreshServiceTest.kt

@@ -3,20 +3,27 @@ package kr.co.vividnext.sodalive.v2.ranking.application
 import kr.co.vividnext.sodalive.v2.ranking.adapter.out.scheduler.CreatorRankingSnapshotScheduler
 import kr.co.vividnext.sodalive.v2.ranking.domain.CreatorRankingSnapshotCandidate
 import kr.co.vividnext.sodalive.v2.ranking.port.out.CreatorRankingAggregationPort
+import kr.co.vividnext.sodalive.v2.ranking.port.out.CreatorRankingAggregationResult
 import kr.co.vividnext.sodalive.v2.ranking.port.out.CreatorRankingSnapshotPort
 import kr.co.vividnext.sodalive.v2.ranking.port.out.CreatorRankingSnapshotRecord
 import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertThrows
 import org.junit.jupiter.api.DisplayName
 import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
 import org.mockito.Mockito
 import org.redisson.api.RLock
 import org.redisson.api.RedissonClient
+import org.springframework.boot.test.system.CapturedOutput
+import org.springframework.boot.test.system.OutputCaptureExtension
 import org.springframework.scheduling.annotation.Scheduled
+import org.springframework.transaction.support.TransactionSynchronizationManager
 import java.time.LocalDateTime
 import java.time.ZoneId
 import java.time.ZonedDateTime
 import java.util.concurrent.TimeUnit
 
+@ExtendWith(OutputCaptureExtension::class)
 class CreatorRankingSnapshotRefreshServiceTest {
     @Test
     @DisplayName("주간 스냅샷 생성은 KST 지난 주를 UTC 조회 기간으로 변환하고 raw 지표 점수를 다시 계산해 저장한다")
@@ -88,6 +95,79 @@ class CreatorRankingSnapshotRefreshServiceTest {
         assertEquals(listOf(2L), snapshotPort.snapshots.map { it.creatorId })
     }
 
+    @Test
+    @DisplayName("주간 스냅샷 생성 성공은 집계 기간과 후보/저장 수를 로그로 남긴다")
+    fun shouldLogSnapshotRefreshSuccessWithPeriodAndCounts(output: CapturedOutput) {
+        val aggregationPort = FakeCreatorRankingAggregationPort()
+        val snapshotPort = FakeCreatorRankingSnapshotPort()
+        val service = service(aggregationPort = aggregationPort, snapshotPort = snapshotPort)
+        aggregationPort.candidates = listOf(
+            candidate(creatorId = 1L, liveCanAmount = 100),
+            candidate(creatorId = 2L, liveCanAmount = 50)
+        )
+
+        service.refreshLastCompletedWeek(ZonedDateTime.of(2026, 6, 8, 6, 0, 0, 0, ZoneId.of("Asia/Seoul")))
+
+        assertEquals(true, output.out.contains("event=creator_ranking_snapshot_refresh_success"))
+        assertEquals(true, output.out.contains("aggregationStartAtUtc=2026-05-31T15:00"))
+        assertEquals(true, output.out.contains("aggregationEndAtUtc=2026-06-07T15:00"))
+        assertEquals(true, output.out.contains("candidateCount=2"))
+        assertEquals(true, output.out.contains("storedCount=2"))
+        assertEquals(true, output.out.contains("lowScoreExcludedCount=0"))
+    }
+
+    @Test
+    @DisplayName("주간 스냅샷 생성 성공 로그는 트랜잭션 커밋 후 기록한다")
+    fun shouldLogSnapshotRefreshSuccessAfterTransactionCommit(output: CapturedOutput) {
+        val aggregationPort = FakeCreatorRankingAggregationPort()
+        val service = service(aggregationPort = aggregationPort)
+        aggregationPort.candidates = listOf(candidate(creatorId = 1L, liveCanAmount = 100))
+
+        TransactionSynchronizationManager.initSynchronization()
+        try {
+            service.refreshLastCompletedWeek(ZonedDateTime.of(2026, 6, 8, 6, 0, 0, 0, ZoneId.of("Asia/Seoul")))
+
+            assertEquals(false, output.out.contains("event=creator_ranking_snapshot_refresh_success"))
+            TransactionSynchronizationManager.getSynchronizations().forEach { it.afterCommit() }
+        } finally {
+            TransactionSynchronizationManager.clearSynchronization()
+        }
+
+        assertEquals(true, output.out.contains("event=creator_ranking_snapshot_refresh_success"))
+    }
+
+    @Test
+    @DisplayName("주간 스냅샷 생성 성공은 최종 점수 1점 미만 제외 수를 로그로 남긴다")
+    fun shouldLogLowScoreExcludedCount(output: CapturedOutput) {
+        val aggregationPort = FakeCreatorRankingAggregationPort()
+        val service = service(aggregationPort = aggregationPort)
+        aggregationPort.candidates = listOf(candidate(creatorId = 1L, liveCanAmount = 100))
+        aggregationPort.lowScoreExcludedCount = 2
+
+        service.refreshLastCompletedWeek(ZonedDateTime.of(2026, 6, 8, 6, 0, 0, 0, ZoneId.of("Asia/Seoul")))
+
+        assertEquals(true, output.out.contains("candidateCount=1"))
+        assertEquals(true, output.out.contains("lowScoreExcludedCount=2"))
+    }
+
+    @Test
+    @DisplayName("주간 스냅샷 생성 실패는 집계 기간과 에러를 로그로 남기고 예외를 전파한다")
+    fun shouldLogSnapshotRefreshFailureWithPeriodAndError(output: CapturedOutput) {
+        val aggregationPort = FakeCreatorRankingAggregationPort()
+        val service = service(aggregationPort = aggregationPort)
+        aggregationPort.failure = IllegalStateException("aggregate failed")
+
+        val exception = assertThrows(IllegalStateException::class.java) {
+            service.refreshLastCompletedWeek(ZonedDateTime.of(2026, 6, 8, 6, 0, 0, 0, ZoneId.of("Asia/Seoul")))
+        }
+
+        assertEquals("aggregate failed", exception.message)
+        assertEquals(true, output.out.contains("event=creator_ranking_snapshot_refresh_failure"))
+        assertEquals(true, output.out.contains("aggregationStartAtUtc=2026-05-31T15:00"))
+        assertEquals(true, output.out.contains("aggregationEndAtUtc=2026-06-07T15:00"))
+        assertEquals(true, output.out.contains("error=aggregate failed"))
+    }
+
     @Test
     @DisplayName("주간 스냅샷 스케줄러는 매주 월요일 07:30 KST cron으로 갱신 서비스를 호출한다")
     fun shouldScheduleWeeklySnapshotRefreshAtKstMondaySevenThirty() {
@@ -194,6 +274,8 @@ class CreatorRankingSnapshotRefreshServiceTest {
 
 private class FakeCreatorRankingAggregationPort : CreatorRankingAggregationPort {
     var candidates: List<CreatorRankingSnapshotCandidate> = emptyList()
+    var lowScoreExcludedCount: Int = 0
+    var failure: RuntimeException? = null
     var startInclusiveUtc: LocalDateTime? = null
     var endExclusiveUtc: LocalDateTime? = null
 
@@ -203,8 +285,22 @@ private class FakeCreatorRankingAggregationPort : CreatorRankingAggregationPort
     ): List<CreatorRankingSnapshotCandidate> {
         this.startInclusiveUtc = startInclusiveUtc
         this.endExclusiveUtc = endExclusiveUtc
+        failure?.let { throw it }
         return candidates
     }
+
+    override fun aggregateCandidateResult(
+        startInclusiveUtc: LocalDateTime,
+        endExclusiveUtc: LocalDateTime
+    ): CreatorRankingAggregationResult {
+        this.startInclusiveUtc = startInclusiveUtc
+        this.endExclusiveUtc = endExclusiveUtc
+        failure?.let { throw it }
+        return CreatorRankingAggregationResult(
+            candidates = candidates,
+            lowScoreExcludedCount = lowScoreExcludedCount
+        )
+    }
 }
 
 private class FakeCreatorRankingSnapshotPort : CreatorRankingSnapshotPort {