first commit

internal/service/notification.go

@@ -0,0 +1,118 @@
+package service
+
+import (
+	"context"
+	"log/slog"
+	"strings"
+
+	"git.lzcwy.cn/zhengchiliu/zt-closet-manage-backend/global"
+	"git.lzcwy.cn/zhengchiliu/zt-closet-manage-backend/internal/dto"
+	"git.lzcwy.cn/zhengchiliu/zt-closet-manage-backend/internal/mysqldao"
+	"git.lzcwy.cn/zhengchiliu/zt-closet-manage-backend/internal/mysqlmodel"
+	"git.lzcwy.cn/zhengchiliu/zt-closet-manage-backend/internal/redisdao"
+	"git.lzcwy.cn/zhengchiliu/zt-closet-manage-backend/pkg/errcode"
+)
+
+// broadcastBatchSize 全量广播每批处理的用户数（分批遍历用户 + 分批插入，避免大事务与内存暴涨）。
+const broadcastBatchSize = 500
+
+// NotificationService 通知推送服务。
+type NotificationService struct {
+	notificationDao *mysqldao.NotificationDao
+	userDao         *mysqldao.UserDao
+}
+
+// NewNotificationService 创建通知服务。
+func NewNotificationService() *NotificationService {
+	return &NotificationService{
+		notificationDao: mysqldao.NewNotificationDao(),
+		userDao:         mysqldao.NewUserDao(),
+	}
+}
+
+// Send 向单个用户发送系统通知（写 user_notifications + Redis 未读计数自增）。
+func (s *NotificationService) Send(ctx context.Context, adminID int64, request *dto.NotificationSendRequest) *errcode.Error {
+	ctx, span := global.Tracer.Start(ctx, "svc.AdminNotificationSend")
+	defer span.End()
+
+	// 校验接收用户存在。
+	if _, err := s.userDao.UserGetByID(ctx, request.UserID); err != nil {
+		if isNotFound(err) {
+			return errcode.UserNotFound
+		}
+		return errcode.DatabaseError
+	}
+
+	notification := buildSystemNotification(request.UserID, request.Title, request.Content)
+	if err := s.notificationDao.NotificationBatchCreate(ctx, []mysqlmodel.UserNotification{notification}); err != nil {
+		return errcode.DatabaseError
+	}
+	s.incrUnread(ctx, request.UserID)
+	return nil
+}
+
+// Broadcast 全量广播系统通知：分批遍历用户写入，返回发送人数。
+func (s *NotificationService) Broadcast(ctx context.Context, adminID int64, request *dto.NotificationBroadcastRequest) (*dto.NotificationBroadcastResponse, *errcode.Error) {
+	ctx, span := global.Tracer.Start(ctx, "svc.AdminNotificationBroadcast")
+	defer span.End()
+
+	title := strings.TrimSpace(request.Title)
+	content := strings.TrimSpace(request.Content)
+
+	var sent int64
+	var lastID int64
+	for {
+		ids, err := s.userDao.UserIDListAll(ctx, lastID, broadcastBatchSize)
+		if err != nil {
+			slog.ErrorContext(ctx, "broadcast fetch user ids failed",
+				"sent", sent, "error", err)
+			return &dto.NotificationBroadcastResponse{SentCount: sent}, errcode.DatabaseError
+		}
+		if len(ids) == 0 {
+			break
+		}
+
+		batch := make([]mysqlmodel.UserNotification, 0, len(ids))
+		for _, uid := range ids {
+			batch = append(batch, buildSystemNotification(uid, title, content))
+		}
+		if err := s.notificationDao.NotificationBatchCreate(ctx, batch); err != nil {
+			slog.ErrorContext(ctx, "broadcast insert batch failed",
+				"sent", sent, "error", err)
+			return &dto.NotificationBroadcastResponse{SentCount: sent}, errcode.DatabaseError
+		}
+		sent += int64(len(ids))
+
+		// best-effort 未读计数自增。
+		for _, uid := range ids {
+			s.incrUnread(ctx, uid)
+		}
+
+		lastID = ids[len(ids)-1]
+		if len(ids) < broadcastBatchSize {
+			break
+		}
+	}
+
+	return &dto.NotificationBroadcastResponse{SentCount: sent}, nil
+}
+
+// incrUnread 未读计数自增（best-effort，失败仅告警，不影响主流程）。
+func (s *NotificationService) incrUnread(ctx context.Context, userID int64) {
+	if _, err := redisdao.NotificationUnreadIncr(ctx, userID); err != nil {
+		slog.WarnContext(ctx, "incr notification unread failed", "user_id", userID, "error", err)
+	}
+}
+
+// buildSystemNotification 构造系统通知记录（msg_type=3、sender_id=0、未读）。
+func buildSystemNotification(userID int64, title, content string) mysqlmodel.UserNotification {
+	return mysqlmodel.UserNotification{
+		NotificationUUID: genUUID(),
+		UserID:           userID,
+		MsgType:          NotificationTypeSystem,
+		SenderID:         NotificationSenderSystem,
+		Title:            strings.TrimSpace(title),
+		Content:          strings.TrimSpace(content),
+		IsRead:           NotificationUnread,
+	}
+}