feat(P3): 私信 + #话题标签 + @提及 完成

backend/internal/feed/entity.go

@@ -1,82 +1,82 @@
-package feed
-
-import "time"
-
-type FeedAuthor struct {
-	ID       uint   `json:"id"`
-	Username string `json:"username"`
-}
-
-type FeedVideoItem struct {
-	ID          uint       `json:"id"`
-	Author      FeedAuthor `json:"author"`
-	Title       string     `json:"title"`
-	Description string     `json:"description,omitempty"`
-	PlayURL     string     `json:"play_url"`
-	CoverURL    string     `json:"cover_url"`
-	CreateTime  int64      `json:"create_time"`
-	LikesCount  int64      `json:"likes_count"`
-	IsLiked     bool       `json:"is_liked"`
-}
-
-type ListLatestRequest struct {
-	Limit      int   `json:"limit"`
-	LatestTime int64 `json:"latest_time"`
-}
-
-type ListLatestResponse struct {
-	VideoList []FeedVideoItem `json:"video_list"`
-	NextTime  int64           `json:"next_time"`
-	HasMore   bool            `json:"has_more"`
-}
-
-type ListLikesCountRequest struct {
-	Limit            int    `json:"limit"`
-	LikesCountBefore *int64 `json:"likes_count_before,omitempty"`
-	IDBefore         *uint  `json:"id_before,omitempty"`
-}
-
-type LikesCountCursor struct {
-	LikesCount int64
-	ID         uint
-}
-
-type ListLikesCountResponse struct {
-	VideoList            []FeedVideoItem `json:"video_list"`
-	NextLikesCountBefore *int64          `json:"next_likes_count_before,omitempty"`
-	NextIDBefore         *uint           `json:"next_id_before,omitempty"`
-	HasMore              bool            `json:"has_more"`
-}
-
-type ListByFollowingRequest struct {
-	Limit      int   `json:"limit"`
-	LatestTime int64 `json:"latest_time"`
-}
-
-type ListByFollowingResponse struct {
-	VideoList []FeedVideoItem `json:"video_list"`
-	NextTime  int64           `json:"next_time"`
-	HasMore   bool            `json:"has_more"`
-}
-
-type ListByPopularityRequest struct {
-	Limit          int   `json:"limit"`
-	AsOf           int64 `json:"as_of"`  // 服务器返回的分钟时间戳；第一页传0
-	Offset         int   `json:"offset"` // 下一页从这里开始；第一页传0
-	LatestIDBefore *uint `json:"latest_id_before,omitempty"`
-
-	// DB fallback 用（可选）
-	LatestPopularity int64     `json:"latest_popularity"`
-	LatestBefore     time.Time `json:"latest_before"`
-}
-
-type ListByPopularityResponse struct {
-	VideoList  []FeedVideoItem `json:"video_list"`
-	AsOf       int64           `json:"as_of"`
-	NextOffset int             `json:"next_offset"`
-	HasMore    bool            `json:"has_more"`
-
-	NextLatestPopularity *int64     `json:"next_latest_popularity,omitempty"`
-	NextLatestBefore     *time.Time `json:"next_latest_before,omitempty"`
-	NextLatestIDBefore   *uint      `json:"next_latest_id_before,omitempty"`
-}
+package feed
+
+import "time"
+
+type FeedAuthor struct {
+	ID       uint   `json:"id"`
+	Username string `json:"username"`
+}
+
+type FeedVideoItem struct {
+	ID          uint       `json:"id"`
+	Author      FeedAuthor `json:"author"`
+	Title       string     `json:"title"`
+	Description string     `json:"description,omitempty"`
+	PlayURL     string     `json:"play_url"`
+	CoverURL    string     `json:"cover_url"`
+	CreateTime  int64      `json:"create_time"`
+	LikesCount  int64      `json:"likes_count"`
+	IsLiked     bool       `json:"is_liked"`
+}
+
+type ListLatestRequest struct {
+	Limit      int   `json:"limit"`
+	LatestTime int64 `json:"latest_time"`
+}
+
+type ListLatestResponse struct {
+	VideoList []FeedVideoItem `json:"video_list"`
+	NextTime  int64           `json:"next_time"`
+	HasMore   bool            `json:"has_more"`
+}
+
+type ListLikesCountRequest struct {
+	Limit            int    `json:"limit"`
+	LikesCountBefore *int64 `json:"likes_count_before,omitempty"`
+	IDBefore         *uint  `json:"id_before,omitempty"`
+}
+
+type LikesCountCursor struct {
+	LikesCount int64
+	ID         uint
+}
+
+type ListLikesCountResponse struct {
+	VideoList            []FeedVideoItem `json:"video_list"`
+	NextLikesCountBefore *int64          `json:"next_likes_count_before,omitempty"`
+	NextIDBefore         *uint           `json:"next_id_before,omitempty"`
+	HasMore              bool            `json:"has_more"`
+}
+
+type ListByFollowingRequest struct {
+	Limit      int   `json:"limit"`
+	LatestTime int64 `json:"latest_time"`
+}
+
+type ListByFollowingResponse struct {
+	VideoList []FeedVideoItem `json:"video_list"`
+	NextTime  int64           `json:"next_time"`
+	HasMore   bool            `json:"has_more"`
+}
+
+type ListByPopularityRequest struct {
+	Limit          int   `json:"limit"`
+	AsOf           int64 `json:"as_of"`  // 服务器返回的分钟时间戳；第一页传0
+	Offset         int   `json:"offset"` // 下一页从这里开始；第一页传0
+	LatestIDBefore *uint `json:"latest_id_before,omitempty"`
+
+	// DB fallback 用（可选）
+	LatestPopularity int64     `json:"latest_popularity"`
+	LatestBefore     time.Time `json:"latest_before"`
+}
+
+type ListByPopularityResponse struct {
+	VideoList  []FeedVideoItem `json:"video_list"`
+	AsOf       int64           `json:"as_of"`
+	NextOffset int             `json:"next_offset"`
+	HasMore    bool            `json:"has_more"`
+
+	NextLatestPopularity *int64     `json:"next_latest_popularity,omitempty"`
+	NextLatestBefore     *time.Time `json:"next_latest_before,omitempty"`
+	NextLatestIDBefore   *uint      `json:"next_latest_id_before,omitempty"`
+}

backend/internal/feed/handler.go

@@ -174,3 +174,28 @@ func nonNilFeedVideoItems(items []FeedVideoItem) []FeedVideoItem {
 	}
 	return items
 }
+
+func (h *FeedHandler) ListByTag(c *gin.Context) {
+	var req struct {
+		TagName string `json:"tag_name"`
+		Limit   int    `json:"limit"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(400, gin.H{"error": err.Error()})
+		return
+	}
+	if req.TagName == "" {
+		c.JSON(400, gin.H{"error": "tag_name is required"})
+		return
+	}
+	if req.Limit <= 0 || req.Limit > 50 {
+		req.Limit = 10
+	}
+	viewerAccountID, _ := jwt.GetAccountID(c)
+	items, err := h.service.ListByTag(c.Request.Context(), req.TagName, req.Limit, viewerAccountID)
+	if err != nil {
+		c.JSON(apierror.ClassifyHTTPStatus(err), gin.H{"error": err.Error()})
+		return
+	}
+	c.JSON(200, gin.H{"video_list": nonNilFeedVideoItems(items)})
+}

backend/internal/feed/repo.go

@@ -1,103 +1,115 @@
-package feed
-
-import (
-	"context"
-	"feedsystem_video_go/internal/social"
-	"feedsystem_video_go/internal/video"
-	"time"
-
-	"gorm.io/gorm"
-)
-
-type FeedRepository struct {
-	db *gorm.DB
-}
-
-func NewFeedRepository(db *gorm.DB) *FeedRepository {
-	return &FeedRepository{db: db}
-}
-
-func (repo *FeedRepository) ListLatest(ctx context.Context, limit int, latestBefore time.Time) ([]*video.Video, error) {
-	var videos []*video.Video
-	query := repo.db.WithContext(ctx).Model(&video.Video{}).
-		Order("create_time DESC")
-	if !latestBefore.IsZero() {
-		query = query.Where("create_time < ?", latestBefore)
-	}
-	if err := query.Limit(limit).Find(&videos).Error; err != nil {
-		return nil, err
-	}
-	return videos, nil
-}
-
-func (repo *FeedRepository) ListLikesCountWithCursor(ctx context.Context, limit int, cursor *LikesCountCursor) ([]*video.Video, error) {
-	var videos []*video.Video
-	query := repo.db.WithContext(ctx).Model(&video.Video{}).
-		Order("likes_count DESC, id DESC")
-
-	if cursor != nil {
-		query = query.Where(
-			"(likes_count < ?) OR (likes_count = ? AND id < ?)",
-			cursor.LikesCount,
-			cursor.LikesCount, cursor.ID,
-		)
-	}
-
-	if err := query.Limit(limit).Find(&videos).Error; err != nil {
-		return nil, err
-	}
-	return videos, nil
-}
-
-func (repo *FeedRepository) ListByFollowing(ctx context.Context, limit int, viewerAccountID uint, latestBefore time.Time) ([]*video.Video, error) {
-	var videos []*video.Video
-	query := repo.db.WithContext(ctx).Model(&video.Video{}).
-		Order("create_time DESC")
-	if viewerAccountID > 0 {
-		followingSubQuery := repo.db.WithContext(ctx).
-			Model(&social.Social{}).
-			Select("vlogger_id").
-			Where("follower_id = ?", viewerAccountID)
-		query = query.Where("author_id IN (?)", followingSubQuery)
-	}
-	if !latestBefore.IsZero() {
-		query = query.Where("create_time < ?", latestBefore)
-	}
-	if err := query.Limit(limit).Find(&videos).Error; err != nil {
-		return nil, err
-	}
-	return videos, nil
-}
-
-func (repo *FeedRepository) ListByPopularity(ctx context.Context, limit int, popularityBefore int64, timeBefore time.Time, idBefore uint) ([]*video.Video, error) {
-	var videos []*video.Video
-	query := repo.db.WithContext(ctx).Model(&video.Video{}).
-		Order("popularity DESC, create_time DESC, id DESC")
-
-	// 只有当游标完整提供时才加过滤（popularity 允许为 0）
-	if !timeBefore.IsZero() && idBefore > 0 {
-		query = query.Where(
-			"(popularity < ?) OR (popularity = ? AND create_time < ?) OR (popularity = ? AND create_time = ? AND id < ?)",
-			popularityBefore,
-			popularityBefore, timeBefore,
-			popularityBefore, timeBefore, idBefore,
-		)
-	}
-
-	if err := query.Limit(limit).Find(&videos).Error; err != nil {
-		return nil, err
-	}
-	return videos, nil
-}
-
-func (repo *FeedRepository) GetByIDs(ctx context.Context, ids []uint) ([]*video.Video, error) {
-	var videos []*video.Video
-	if len(ids) == 0 {
-		return videos, nil
-	}
-	if err := repo.db.WithContext(ctx).Model(&video.Video{}).
-		Where("id IN ?", ids).Find(&videos).Error; err != nil {
-		return nil, err
-	}
-	return videos, nil
+package feed
+
+import (
+	"context"
+	"feedsystem_video_go/internal/social"
+	"feedsystem_video_go/internal/video"
+	"time"
+
+	"gorm.io/gorm"
+)
+
+type FeedRepository struct {
+	db *gorm.DB
+}
+
+func NewFeedRepository(db *gorm.DB) *FeedRepository {
+	return &FeedRepository{db: db}
+}
+
+func (repo *FeedRepository) ListLatest(ctx context.Context, limit int, latestBefore time.Time) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("create_time DESC")
+	if !latestBefore.IsZero() {
+		query = query.Where("create_time < ?", latestBefore)
+	}
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) ListLikesCountWithCursor(ctx context.Context, limit int, cursor *LikesCountCursor) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("likes_count DESC, id DESC")
+
+	if cursor != nil {
+		query = query.Where(
+			"(likes_count < ?) OR (likes_count = ? AND id < ?)",
+			cursor.LikesCount,
+			cursor.LikesCount, cursor.ID,
+		)
+	}
+
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) ListByFollowing(ctx context.Context, limit int, viewerAccountID uint, latestBefore time.Time) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("create_time DESC")
+	if viewerAccountID > 0 {
+		followingSubQuery := repo.db.WithContext(ctx).
+			Model(&social.Social{}).
+			Select("vlogger_id").
+			Where("follower_id = ?", viewerAccountID)
+		query = query.Where("author_id IN (?)", followingSubQuery)
+	}
+	if !latestBefore.IsZero() {
+		query = query.Where("create_time < ?", latestBefore)
+	}
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) ListByPopularity(ctx context.Context, limit int, popularityBefore int64, timeBefore time.Time, idBefore uint) ([]*video.Video, error) {
+	var videos []*video.Video
+	query := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Order("popularity DESC, create_time DESC, id DESC")
+
+	// 只有当游标完整提供时才加过滤（popularity 允许为 0）
+	if !timeBefore.IsZero() && idBefore > 0 {
+		query = query.Where(
+			"(popularity < ?) OR (popularity = ? AND create_time < ?) OR (popularity = ? AND create_time = ? AND id < ?)",
+			popularityBefore,
+			popularityBefore, timeBefore,
+			popularityBefore, timeBefore, idBefore,
+		)
+	}
+
+	if err := query.Limit(limit).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) GetByIDs(ctx context.Context, ids []uint) ([]*video.Video, error) {
+	var videos []*video.Video
+	if len(ids) == 0 {
+		return videos, nil
+	}
+	if err := repo.db.WithContext(ctx).Model(&video.Video{}).
+		Where("id IN ?", ids).Find(&videos).Error; err != nil {
+		return nil, err
+	}
+	return videos, nil
+}
+
+func (repo *FeedRepository) ListByTag(ctx context.Context, tagName string, limit int) ([]*video.Video, error) {
+	var videos []*video.Video
+	err := repo.db.WithContext(ctx).Model(&video.Video{}).Table("videos").
+		Joins("JOIN video_tags ON video_tags.video_id = videos.id").
+		Joins("JOIN tags ON tags.id = video_tags.tag_id").
+		Where("tags.name = ?", tagName).
+		Order("videos.create_time desc").
+		Limit(limit).
+		Find(&videos).Error
+	return videos, err
 }

backend/internal/feed/service.go

@@ -545,3 +545,11 @@ func buildOrderedResult(orderedIDs []uint, dataMap map[uint]*video.Video) []*vid
 	}
 	return res
 }
+
+func (f *FeedService) ListByTag(ctx context.Context, tagName string, limit int, viewerAccountID uint) ([]FeedVideoItem, error) {
+	videos, err := f.repo.ListByTag(ctx, tagName, limit)
+	if err != nil {
+		return nil, err
+	}
+	return f.buildFeedVideos(ctx, videos, viewerAccountID)
+}

backend/internal/http/router.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"feedsystem_video_go/internal/account"
 	"feedsystem_video_go/internal/feed"
+	"feedsystem_video_go/internal/message"
 	"feedsystem_video_go/internal/middleware/jwt"
 	"feedsystem_video_go/internal/middleware/ratelimit"
 	"feedsystem_video_go/internal/middleware/rabbitmq"
@@ -166,12 +167,25 @@ func SetRouter(db *gorm.DB, cache *rediscache.Client, rmq *rabbitmq.RabbitMQ) *g
 		feedGroup.POST("/listLatest", feedHandler.ListLatest)
 		feedGroup.POST("/listLikesCount", feedHandler.ListLikesCount)
 		feedGroup.POST("/listByPopularity", feedHandler.ListByPopularity)
+		feedGroup.POST("/listByTag", feedHandler.ListByTag)
 	}
 	protectedFeedGroup := feedGroup.Group("")
 	protectedFeedGroup.Use(jwt.JWTAuth(accountRepository, cache))
 	{
 		protectedFeedGroup.POST("/listByFollowing", feedHandler.ListByFollowing)
 	}
+	// message
+	messageRepo := message.NewRepository(db)
+	_ = messageRepo.AutoMigrate(context.Background())
+	messageService := message.NewService(messageRepo)
+	messageHandler := message.NewHandler(messageService)
+	messageGroup := r.Group("/message")
+	protectedMessageGroup := messageGroup.Group("")
+	protectedMessageGroup.Use(jwt.JWTAuth(accountRepository, cache))
+	{
+		protectedMessageGroup.POST("/send", messageHandler.Send)
+		protectedMessageGroup.POST("/list", messageHandler.List)
+	}
 	//worker
 	timelineMQ, err := rabbitmq.NewTimelineMQ(rmq)
 	if err != nil {

backend/internal/message/entity.go

@@ -0,0 +1,25 @@
+package message
+
+import "time"
+
+type Message struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	FromID    uint      `gorm:"index:idx_message_from;not null" json:"from_id"`
+	ToID      uint      `gorm:"index:idx_message_to;not null" json:"to_id"`
+	Content   string    `gorm:"type:text;not null" json:"content"`
+	IsRead    bool      `gorm:"default:false" json:"is_read"`
+	CreatedAt time.Time `gorm:"autoCreateTime" json:"created_at"`
+}
+
+type SendRequest struct {
+	ToID    uint   `json:"to_id"`
+	Content string `json:"content"`
+}
+
+type ListRequest struct {
+	PeerID uint `json:"peer_id"`
+}
+
+type ListResponse struct {
+	Messages []Message `json:"messages"`
+}

backend/internal/message/handler.go

@@ -0,0 +1,95 @@
+package message
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"time"
+
+	"feedsystem_video_go/internal/apierror"
+	"feedsystem_video_go/internal/middleware/jwt"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"gorm.io/gorm"
+)
+
+type Repository struct{ db *gorm.DB }
+type Service struct{ repo *Repository }
+type Handler struct{ service *Service }
+
+func NewRepository(db *gorm.DB) *Repository { return &Repository{db: db} }
+func NewService(repo *Repository) *Service   { return &Service{repo: repo} }
+func NewHandler(service *Service) *Handler   { return &Handler{service: service} }
+
+func (r *Repository) AutoMigrate(ctx context.Context) error {
+	return r.db.WithContext(ctx).AutoMigrate(&Message{})
+}
+
+func (r *Repository) Send(ctx context.Context, m *Message) error {
+	m.Content = strings.TrimSpace(m.Content)
+	if m.Content == "" {
+		return errors.New("content is required")
+	}
+	m.CreatedAt = time.Now()
+	return r.db.WithContext(ctx).Create(m).Error
+}
+
+func (r *Repository) List(ctx context.Context, userID, peerID uint, limit int) ([]Message, error) {
+	var msgs []Message
+	err := r.db.WithContext(ctx).
+		Where("(from_id = ? AND to_id = ?) OR (from_id = ? AND to_id = ?)", userID, peerID, peerID, userID).
+		Order("created_at desc").
+		Limit(limit).
+		Find(&msgs).Error
+	return msgs, err
+}
+
+func (h *Handler) Send(c *gin.Context) {
+	fromID, err := jwt.GetAccountID(c)
+	if err != nil {
+		c.JSON(http.StatusUnauthorized, gin.H{"error": err.Error()})
+		return
+	}
+	var req SendRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	if req.ToID == 0 || strings.TrimSpace(req.Content) == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "to_id and content are required"})
+		return
+	}
+	m := &Message{FromID: fromID, ToID: req.ToID, Content: req.Content}
+	if err := h.service.repo.Send(c.Request.Context(), m); err != nil {
+		c.JSON(apierror.ClassifyHTTPStatus(err), gin.H{"error": err.Error()})
+		return
+	}
+	c.JSON(http.StatusOK, m)
+}
+
+func (h *Handler) List(c *gin.Context) {
+	userID, err := jwt.GetAccountID(c)
+	if err != nil {
+		c.JSON(http.StatusUnauthorized, gin.H{"error": err.Error()})
+		return
+	}
+	var req ListRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	if req.PeerID == 0 {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "peer_id is required"})
+		return
+	}
+	msgs, err := h.service.repo.List(c.Request.Context(), userID, req.PeerID, 50)
+	if err != nil {
+		c.JSON(apierror.ClassifyHTTPStatus(err), gin.H{"error": err.Error()})
+		return
+	}
+	if msgs == nil {
+		msgs = []Message{}
+	}
+	c.JSON(http.StatusOK, ListResponse{Messages: msgs})
+}

backend/internal/video/comment_service.go

@@ -6,6 +6,7 @@ import (
 	"feedsystem_video_go/internal/middleware/rabbitmq"
 	rediscache "feedsystem_video_go/internal/middleware/redis"
 	"feedsystem_video_go/internal/apierror"
+	"regexp"
 	"strings"
 
 	"gorm.io/gorm"
@@ -57,6 +58,7 @@ func (s *CommentService) Publish(ctx context.Context, comment *Comment) error {
 		}
 	}
 	if mysqlEnqueued && redisEnqueued {
+		s.notifyMentions(ctx, comment)
 		return nil
 	}
 
@@ -83,6 +85,7 @@ func (s *CommentService) Publish(ctx context.Context, comment *Comment) error {
 	if !redisEnqueued {
 		UpdatePopularityCache(ctx, s.cache, comment.VideoID, 1)
 	}
+	s.notifyMentions(ctx, comment)
 	return nil
 }
 
@@ -115,3 +118,38 @@ func (s *CommentService) GetAll(ctx context.Context, videoID uint) ([]Comment, e
 	}
 	return s.repo.GetAllComments(ctx, videoID)
 }
+
+var mentionRegex = regexp.MustCompile(`@(\w+)`)
+
+func (s *CommentService) notifyMentions(ctx context.Context, comment *Comment) {
+	matches := mentionRegex.FindAllStringSubmatch(comment.Content, -1)
+	if len(matches) == 0 {
+		return
+	}
+	seen := make(map[string]bool)
+	for _, m := range matches {
+		username := m[1]
+		if seen[username] || username == comment.Username {
+			continue
+		}
+		seen[username] = true
+		var accID uint
+		if err := s.repo.db.WithContext(ctx).Table("accounts").Where("username = ?", username).Select("id").Scan(&accID).Error; err != nil || accID == 0 {
+			continue
+		}
+		notif := struct {
+			RecipientID uint
+			SenderID    uint
+			Type        string
+			TargetID    uint
+			Content     string
+		}{
+			RecipientID: accID,
+			SenderID:    comment.AuthorID,
+			Type:        "mention",
+			TargetID:    comment.VideoID,
+			Content:     comment.Username + " 在评论中提到了你",
+		}
+		s.repo.db.WithContext(ctx).Table("notifications").Create(&notif)
+	}
+}

backend/internal/video/tag_entity.go

@@ -0,0 +1,30 @@
+package video
+
+import "regexp"
+
+type Tag struct {
+	ID   uint   `gorm:"primaryKey" json:"id"`
+	Name string `gorm:"uniqueIndex;type:varchar(100);not null" json:"name"`
+}
+
+type VideoTag struct {
+	ID      uint `gorm:"primaryKey"`
+	VideoID uint `gorm:"index;not null"`
+	TagID   uint `gorm:"index;not null"`
+}
+
+var tagRegex = regexp.MustCompile(`#([\p{L}\p{N}_]+)`)
+
+func ExtractTags(text string) []string {
+	matches := tagRegex.FindAllStringSubmatch(text, -1)
+	seen := make(map[string]bool)
+	var tags []string
+	for _, m := range matches {
+		tag := m[1]
+		if !seen[tag] {
+			seen[tag] = true
+			tags = append(tags, tag)
+		}
+	}
+	return tags
+}

backend/internal/video/video_service.go

@@ -60,8 +60,14 @@ func (vs *VideoService) Publish(ctx context.Context, video *Video) error {
 		if err := tx.Create(&msg).Error; err != nil {
 			return err
 		}
-		return nil
 
+		tags := ExtractTags(video.Title + " " + video.Description)
+		for _, tagName := range tags {
+			var tag Tag
+			tx.Where("name = ?", tagName).FirstOrCreate(&tag, Tag{Name: tagName})
+			tx.Create(&VideoTag{VideoID: video.ID, TagID: tag.ID})
+		}
+		return nil
 	})
 	return err