feat(hot-rank): add per-channel hot ranking functionality

Add channel-specific hot post filtering and ranking across the posts listing flow. Introduce refreshChannelRanks to compute per-channel hot scores, new Redis cache keys for channel hot ranks, and update repository/service/handler layers to accept channelID filtering parameters. Update HotRankWorker dependency injection to include ChannelRepository.
2026-04-26 11:39:41 +08:00
parent 02466603f9
commit 27ea8689f9
7 changed files with 329 additions and 70 deletions
--- a/internal/service/post_service.go
+++ b/internal/service/post_service.go
@@ -44,12 +44,12 @@ type PostService interface {
 	ListByCursor(ctx context.Context, userID string, includePending bool, channelID *string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)
 	SearchByCursor(ctx context.Context, keyword string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)
 	GetUserPostsByCursor(ctx context.Context, userID string, includePending bool, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)
-	GetFollowingPostsByCursor(ctx context.Context, userID string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)
-	GetHotPostsByCursor(ctx context.Context, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)
+	GetFollowingPostsByCursor(ctx context.Context, userID string, channelID *string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)
+	GetHotPostsByCursor(ctx context.Context, channelID *string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error)

 	// 关注和推荐
-	GetFollowingPosts(ctx context.Context, userID string, page, pageSize int) ([]*model.Post, int64, error)
-	GetHotPosts(ctx context.Context, page, pageSize int) ([]*model.Post, int64, error)
+	GetFollowingPosts(ctx context.Context, userID string, page, pageSize int, channelID *string) ([]*model.Post, int64, error)
+	GetHotPosts(ctx context.Context, page, pageSize int, channelID *string) ([]*model.Post, int64, error)

 	// 交互功能
 	Like(ctx context.Context, postID, userID string) error
@@ -560,7 +560,7 @@ func (s *postServiceImpl) Search(ctx context.Context, keyword string, page, page
 }

 // GetFollowingPosts 获取关注用户的帖子（带缓存）
-func (s *postServiceImpl) GetFollowingPosts(ctx context.Context, userID string, page, pageSize int) ([]*model.Post, int64, error) {
+func (s *postServiceImpl) GetFollowingPosts(ctx context.Context, userID string, page, pageSize int, channelID *string) ([]*model.Post, int64, error) {
 	cacheSettings := cache.GetSettings()
 	postListTTL := cacheSettings.PostListTTL
 	if postListTTL <= 0 {
@@ -575,8 +575,11 @@ func (s *postServiceImpl) GetFollowingPosts(ctx context.Context, userID string,
 		jitter = PostListJitterRatio
 	}

-	// 生成缓存键
-	cacheKey := cache.PostListKey("follow", userID, page, pageSize)
+	cacheSuffix := ""
+	if channelID != nil && *channelID != "" {
+		cacheSuffix = ":ch:" + *channelID
+	}
+	cacheKey := cache.PostListKey("follow", userID+cacheSuffix, page, pageSize)

 	result, err := cache.GetOrLoadTyped[*PostListResult](
 		s.cache,
@@ -585,7 +588,7 @@ func (s *postServiceImpl) GetFollowingPosts(ctx context.Context, userID string,
 		jitter,
 		nullTTL,
 		func() (*PostListResult, error) {
-			posts, total, err := s.postRepo.GetFollowingPosts(userID, page, pageSize)
+			posts, total, err := s.postRepo.GetFollowingPosts(userID, page, pageSize, channelID)
 			if err != nil {
 				return nil, err
 			}
@@ -602,8 +605,16 @@ func (s *postServiceImpl) GetFollowingPosts(ctx context.Context, userID string,
 }

 // GetHotPosts 获取热门帖子（优先分层缓存 top_ids → Redis ZSET，未就绪时回源 DB 按最新排序）
-func (s *postServiceImpl) GetHotPosts(ctx context.Context, page, pageSize int) ([]*model.Post, int64, error) {
+func (s *postServiceImpl) GetHotPosts(ctx context.Context, page, pageSize int, channelID *string) ([]*model.Post, int64, error) {
 	offset := (page - 1) * pageSize
+	if channelID != nil && *channelID != "" {
+		if posts, total, ok, err := s.tryHotPostsFromChannelCache(ctx, *channelID, offset, pageSize); ok {
+			return posts, total, err
+		} else if err != nil {
+			return nil, 0, err
+		}
+		return s.getHotPostsFromDB(ctx, page, pageSize, channelID)
+	}
 	if posts, total, ok, err := s.tryHotPostsFromTopIDsCache(offset, pageSize); ok {
 		return posts, total, err
 	} else if err != nil {
@@ -614,7 +625,42 @@ func (s *postServiceImpl) GetHotPosts(ctx context.Context, page, pageSize int) (
 	} else if err != nil {
 		return nil, 0, err
 	}
-	return s.getHotPostsFromDB(ctx, page, pageSize)
+	return s.getHotPostsFromDB(ctx, page, pageSize, nil)
+}
+
+func (s *postServiceImpl) tryHotPostsFromChannelCache(ctx context.Context, channelID string, offset, pageSize int) (posts []*model.Post, total int64, ok bool, err error) {
+	if s.cache == nil || pageSize <= 0 {
+		return nil, 0, false, nil
+	}
+	topIDsKey := cache.HotRankTopIDsChannelKey(channelID)
+	ids, hit := cache.GetTyped[[]string](s.cache, topIDsKey)
+	if hit && len(ids) > 0 {
+		if offset >= len(ids) {
+			return []*model.Post{}, int64(len(ids)), true, nil
+		}
+		end := offset + pageSize
+		if end > len(ids) {
+			end = len(ids)
+		}
+		posts, err = s.postRepo.GetByIDs(ids[offset:end])
+		if err != nil {
+			return nil, 0, false, err
+		}
+		return posts, int64(len(ids)), true, nil
+	}
+	zsetKey := cache.HotRankZSetChannelKey(channelID)
+	card, zerr := s.cache.ZCard(ctx, zsetKey)
+	if zerr == nil && card > 0 {
+		ids, zerr = s.cache.ZRevRange(ctx, zsetKey, int64(offset), int64(offset+pageSize-1))
+		if zerr == nil && len(ids) > 0 {
+			posts, err = s.postRepo.GetByIDs(ids)
+			if err != nil {
+				return nil, 0, false, err
+			}
+			return posts, card, true, nil
+		}
+	}
+	return nil, 0, false, nil
 }

 // tryHotPostsFromTopIDsCache 从热门榜有序 ID 列表取帖（命中 LayeredCache 本地层时可不访问 Redis）
@@ -664,8 +710,8 @@ func (s *postServiceImpl) tryHotPostsFromZSet(ctx context.Context, offset, pageS
 }

 // getHotPostsFromDB 热门未就绪时按最新发布降级
-func (s *postServiceImpl) getHotPostsFromDB(ctx context.Context, page, pageSize int) ([]*model.Post, int64, error) {
-	posts, total, err := s.postRepo.GetHotPosts(page, pageSize)
+func (s *postServiceImpl) getHotPostsFromDB(ctx context.Context, page, pageSize int, channelID *string) ([]*model.Post, int64, error) {
+	posts, total, err := s.postRepo.GetHotPosts(page, pageSize, channelID)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -713,23 +759,21 @@ func (s *postServiceImpl) GetUserPostsByCursor(ctx context.Context, userID strin
 }

 // GetFollowingPostsByCursor 游标分页获取关注用户的帖子
-func (s *postServiceImpl) GetFollowingPostsByCursor(ctx context.Context, userID string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error) {
-	// 规范化请求参数
+func (s *postServiceImpl) GetFollowingPostsByCursor(ctx context.Context, userID string, channelID *string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error) {
 	req.Normalize()

-	return s.postRepo.GetFollowingPostsByCursor(ctx, userID, req)
+	return s.postRepo.GetFollowingPostsByCursor(ctx, userID, channelID, req)
 }

 // GetHotPostsByCursor 游标分页获取热门帖子
-func (s *postServiceImpl) GetHotPostsByCursor(ctx context.Context, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error) {
-	// 规范化请求参数
+func (s *postServiceImpl) GetHotPostsByCursor(ctx context.Context, channelID *string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error) {
 	req.Normalize()

-	return s.getHotPostsByCursorFromDB(ctx, req)
+	return s.getHotPostsByCursorFromDB(ctx, channelID, req)
 }

 // getHotPostsByCursorFromDB 热门游标：优先 ZSET（一次多取 1 条判断 hasMore），否则回源 DB
-func (s *postServiceImpl) getHotPostsByCursorFromDB(ctx context.Context, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error) {
+func (s *postServiceImpl) getHotPostsByCursorFromDB(ctx context.Context, channelID *string, req *cursor.PageRequest) (*cursor.CursorPageResult[*model.Post], error) {
 	offset := 0
 	if req.Cursor != "" {
 		if parsed, err := strconv.Atoi(req.Cursor); err == nil && parsed >= 0 {
@@ -738,7 +782,14 @@ func (s *postServiceImpl) getHotPostsByCursorFromDB(ctx context.Context, req *cu
 	}

 	if s.cache != nil {
-		if ids, hit := cache.GetTyped[[]string](s.cache, cache.HotRankTopIDsKey()); hit && len(ids) > 0 {
+		topIDsKey := cache.HotRankTopIDsKey()
+		zsetKey := cache.HotRankZSetKey()
+		if channelID != nil && *channelID != "" {
+			topIDsKey = cache.HotRankTopIDsChannelKey(*channelID)
+			zsetKey = cache.HotRankZSetChannelKey(*channelID)
+		}
+
+		if ids, hit := cache.GetTyped[[]string](s.cache, topIDsKey); hit && len(ids) > 0 {
 			if offset < len(ids) {
 				stop := offset + req.PageSize + 1
 				if stop > len(ids) {
@@ -772,11 +823,10 @@ func (s *postServiceImpl) getHotPostsByCursorFromDB(ctx context.Context, req *cu
 			}, nil
 		}

-		key := cache.HotRankZSetKey()
-		card, zerr := s.cache.ZCard(ctx, key)
+		card, zerr := s.cache.ZCard(ctx, zsetKey)
 		if zerr == nil && card > 0 {
 			stop := int64(offset + req.PageSize)
-			ids, rerr := s.cache.ZRevRange(ctx, key, int64(offset), stop)
+			ids, rerr := s.cache.ZRevRange(ctx, zsetKey, int64(offset), stop)
 			if rerr == nil && len(ids) > 0 {
 				hasMore := len(ids) > req.PageSize
 				if hasMore {
@@ -801,7 +851,7 @@ func (s *postServiceImpl) getHotPostsByCursorFromDB(ctx context.Context, req *cu
 	}

 	page := offset/req.PageSize + 1
-	posts, _, err := s.postRepo.GetHotPosts(page, req.PageSize+1)
+	posts, _, err := s.postRepo.GetHotPosts(page, req.PageSize+1, channelID)
 	if err != nil {
 		return nil, err
 	}