func()

in service/recall/hologres_vector_recall_v2.go [96:210]
105 lines of code
22 McCabe index (conditional complexity)

func (r *HologresVectorRecallV2) GetCandidateItems(user *module.User, context *context.RecommendContext) (ret []*module.Item) {
	start := time.Now()

	var userEmbedding string
	userEmbKey := r.cachePrefix + string(user.Id)
	if value, ok := r.userVectorCache.GetIfPresent(userEmbKey); ok {
		userEmbedding = value.(string)
		user.AddProperty(r.modelName+"_embedding", userEmbedding)
	} else {
		emb, err := r.dao.VectorString(string(user.Id))
		if err != nil {
			if !errors.Is(err, module.VectoryEmptyError) {
				context.LogError(fmt.Sprintf("get user vector failed. %s, err=%v", r.modelName, err))
			}
		} else if emb != "" {
			user.AddProperty(r.modelName+"_embedding", emb)
			r.userVectorCache.Put(userEmbKey, emb)
			userEmbedding = emb
		}
	}

	ret = make([]*module.Item, 0, r.recallCount)
	if r.cache != nil {
		key := r.cachePrefix + string(user.Id)
		cacheRet := r.cache.Get(key)
		if itemStr, ok := cacheRet.([]uint8); ok {
			itemIds := strings.Split(string(itemStr), ",")
			for _, id := range itemIds {
				var item *module.Item
				if strings.Contains(id, ":") {
					vars := strings.Split(id, ":")
					item = module.NewItem(vars[0])
					f, _ := strconv.ParseFloat(vars[2], 64)
					// item.AddProperty(vars[1], f)
					item.Score = f
				} else {
					item = module.NewItem(id)
				}
				item.RetrieveId = r.modelName
				item.ItemType = r.itemType
				ret = append(ret, item)
			}
			context.LogInfo(fmt.Sprintf("requestId=%s\tmodule=HologresVectorRecallV2\tname=%s\thit cache\tcount=%d\tcost=%d",
				context.RecommendId, r.modelName, len(ret), utils.CostTime(start)))
			return
		}
	}

	if userEmbedding == "" {
		return
	}

	if r.dbStmt == nil {
		r.mu.Lock()
		if r.dbStmt == nil {
			r.sql = fmt.Sprintf(hologres_vector_sql_v2, r.vectorKeyField, r.vectorEmbeddingField, r.table, r.where, r.recallCount)
			if context.Debug {
				context.LogInfo("module=HologresVectorRecallV2\tsql=" + r.sql)
			}
			stmt, err := r.db.Prepare(r.sql)
			if err != nil {
				log.Error(fmt.Sprintf("requestId=%s\tmodule=HologresVectorRecallV2\tname=%s\terr=%v", context.RecommendId, r.modelName, err))
				r.mu.Unlock()
				return
			}
			r.dbStmt = stmt
			r.mu.Unlock()
		} else {
			r.mu.Unlock()
		}
	}

	rows, err := r.dbStmt.Query(userEmbedding)
	if err != nil {
		emb := userEmbedding
		if len(userEmbedding) > 500 {
			emb = userEmbedding[:500]
		}
		log.Error(fmt.Sprintf("requestId=%s\tmodule=HologresVectorRecallV2\tname=%s\tsql=%s\tuser_embedding=%s\terr=%v", context.RecommendId, r.modelName, r.sql, emb, err))
		return
	}

	defer rows.Close()
	for rows.Next() {
		var itemId string
		var distance float64
		if err := rows.Scan(&itemId, &distance); err != nil {
			continue
		}

		item := module.NewItem(itemId)
		item.RetrieveId = r.modelName
		item.ItemType = r.itemType
		item.Score = distance

		ret = append(ret, item)
	}

	if r.cache != nil && len(ret) > 0 {
		go func() {
			key := r.cachePrefix + string(user.Id)
			var itemIds string
			for _, item := range ret {
				itemIds += fmt.Sprintf("%s:%s:%v", string(item.Id), r.modelName, item.Score) + ","
			}
			itemIds = itemIds[:len(itemIds)-1]
			if err2 := r.cache.Put(key, itemIds, time.Duration(r.cacheTime)*time.Second); err2 != nil {
				context.LogError(fmt.Sprintf("module=HologresVectorRecall\terror=%v", err2))
			}
		}()
	}
	log.Info(fmt.Sprintf("requestId=%s\tmodule=HologresVectorRecallV2\tname=%s\tcount=%d\tcost=%d",
		context.RecommendId, r.modelName, len(ret), utils.CostTime(start)))
	return
}