feat(discover): ChannelDiscoveryService(지역 Shorts 검색→떡상 채널 upsert)+설정

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/main/java/com/hlab/yanalyst/domain/channel/ChannelDiscoveryService.java

@@ -0,0 +1,109 @@
+package com.hlab.yanalyst.domain.channel;
+
+import com.hlab.yanalyst.global.schedule.YoutubeQuotaGuard;
+import com.hlab.yanalyst.service.YoutubeSearchService;
+import com.hlab.yanalyst.web.dto.YoutubeSearchCondition;
+import com.hlab.yanalyst.web.dto.YoutubeSearchPageDto;
+import com.hlab.yanalyst.web.dto.YoutubeSearchResultDto;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/** 지역 인기 Shorts 검색 → 떡상 채널 발굴 → RecommendedChannel upsert. */
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class ChannelDiscoveryService {
+
+    /** search.list 1회 추정 쿼터(units). */
+    private static final long SEARCH_QUOTA = 100;
+
+    private final YoutubeSearchService youtubeSearchService;
+    private final YoutubeQuotaGuard quotaGuard;
+    private final ChannelRepository channelRepository;
+    private final RecommendedChannelRepository recommendedChannelRepository;
+
+    @Value("${hlab.discovery.regions:KR,JP,US}")
+    private String regionsCsv;
+    @Value("${hlab.discovery.max-subscribers:100000}")
+    private long maxSubscribers;
+    @Value("${hlab.discovery.min-ratio:5.0}")
+    private double minRatio;
+    @Value("${hlab.discovery.period-days:14}")
+    private int periodDays;
+
+    @Transactional
+    public Map<String, Object> runDiscovery() {
+        List<String> regions = Arrays.stream(regionsCsv.split(","))
+                .map(String::trim).filter(s -> !s.isBlank()).toList();
+
+        List<YoutubeSearchResultDto> all = new ArrayList<>();
+        List<String> searchedRegions = new ArrayList<>();
+        for (String region : regions) {
+            if (!quotaGuard.tryConsume(SEARCH_QUOTA)) {
+                log.warn("[Discovery] 쿼터 예산 소진 — 지역 {} 이후 건너뜀 (잔여 {})", region, quotaGuard.remaining());
+                break;
+            }
+            try {
+                YoutubeSearchCondition cond = new YoutubeSearchCondition();
+                cond.setRegions(List.of(region));
+                cond.setFormat("SHORTS");
+                cond.setPeriodDays(periodDays);
+                // 광범위 검색: 키워드 없이 인기 Shorts. 결과 빈약 시 검색 API 보강 필요(스펙 §4.2).
+                YoutubeSearchPageDto page = youtubeSearchService.searchYoutubeVideos(cond);
+                if (page != null && page.getItems() != null) all.addAll(page.getItems());
+                searchedRegions.add(region);
+            } catch (Exception e) {
+                log.error("[Discovery] 지역 {} 검색 실패 — 건너뜀", region, e);
+            }
+        }
+
+        // 이미 제외(EXCLUDED)한 채널 제외
+        Set<String> exclude = new HashSet<>();
+        for (RecommendedChannel rc : recommendedChannelRepository.findByStatusOrderByRatioDesc("EXCLUDED")) {
+            exclude.add(rc.getChannelId());
+        }
+
+        List<DiscoveryRanker.Candidate> ranked = DiscoveryRanker.rank(all, maxSubscribers, minRatio, exclude);
+
+        int saved = 0;
+        for (DiscoveryRanker.Candidate c : ranked) {
+            if (channelRepository.existsByChannelId(c.channelId())) continue; // 이미 내 채널
+            RecommendedChannel rc = recommendedChannelRepository.findByChannelId(c.channelId())
+                    .orElseGet(RecommendedChannel::new);
+            if ("EXCLUDED".equals(rc.getStatus()) || "REGISTERED".equals(rc.getStatus())) continue;
+            // 기존 NEW 항목이면 더 높은 배율일 때만 갱신
+            if (rc.getId() != null && rc.getRatio() != null && c.ratio() <= rc.getRatio()) continue;
+            rc.setChannelId(c.channelId());
+            rc.setChannelTitle(c.channelTitle());
+            rc.setThumbnailUrl(c.thumbnailUrl());
+            rc.setSubscriberCount(c.subscriberCount());
+            rc.setStatus("NEW");
+            rc.setTopVideoId(c.topVideoId());
+            rc.setTopVideoTitle(c.topVideoTitle());
+            rc.setTopVideoViewCount(c.topVideoViewCount());
+            rc.setRatio(c.ratio());
+            rc.setRegion(c.region());
+            recommendedChannelRepository.save(rc);
+            saved++;
+        }
+
+        Map<String, Object> summary = new LinkedHashMap<>();
+        summary.put("regions", searchedRegions);
+        summary.put("candidates", ranked.size());
+        summary.put("saved", saved);
+        summary.put("quotaRemaining", quotaGuard.remaining());
+        log.info("[Discovery] 완료: {}", summary);
+        return summary;
+    }
+}

src/main/resources/application.yml

@@ -81,5 +81,15 @@ hlab:
     channel-snapshot:
       enabled: ${CHANNEL_SNAPSHOT_ENABLED:true}
       cron: ${CHANNEL_SNAPSHOT_CRON:0 0 3 * * *}     # 매일 03:00 (성장 추이 기록)
+    channel-discovery:
+      enabled: ${CHANNEL_DISCOVERY_ENABLED:true}
+      cron: ${CHANNEL_DISCOVERY_CRON:0 30 4 * * *}   # 매일 04:30 (추천 채널 발굴)
   youtube:
     daily-quota: ${YOUTUBE_DAILY_QUOTA:10000}        # 자동 수집이 소비할 수 있는 일일 쿼터 상한(추정)
+  # 추천 채널 발굴: 지역 인기 Shorts 에서 작은구독자·고배율 떡상 채널 발굴
+  discovery:
+    regions: ${DISCOVERY_REGIONS:KR,JP,US}
+    max-subscribers: ${DISCOVERY_MAX_SUBS:100000}    # 작은 채널 상한
+    min-ratio: ${DISCOVERY_MIN_RATIO:5.0}            # 떡상 배율 하한
+    period-days: ${DISCOVERY_PERIOD_DAYS:14}         # 최근 N일 영상 대상
+    top-n: ${DISCOVERY_TOP_N:30}