smart_intersectionV2.0/server/utils/cache/device_redis.go

package cache

import (
	"context"
	"encoding/json"
	"fmt"
	"github.com/redis/go-redis/v9"
	"server/global"
	"server/utils/common"
	"time"
)

var Redis redis.UniversalClient

func init() {
	Redis = global.GVA_REDIS
}

const (
	//设备在线状态
	DeviceStateKey = "dev_camera_state_%s"
)

func CacheDeviceInfoKey(sn string) string {
	return fmt.Sprintf(DeviceStateKey, sn)
}

type CacheDeviceInfo struct {
	LastTime *common.Time //同步时间
	Status   int          //0不在线 1在线
}

// UpdateDeviceState 更新设备缓存的状态
func UpdateDeviceState(sn string, status int) bool {
	lastTime := common.Time(time.Now())
	deviceInfo, _ := json.Marshal(CacheDeviceInfo{
		LastTime: &lastTime,
		Status:   status,
	})
	if global.GVA_REDIS == nil {
		return false
	}
	err := global.GVA_REDIS.Set(context.Background(), CacheDeviceInfoKey(sn), deviceInfo, 0)
	if err.Err() != nil {
		global.GVA_LOG.Error(err.String())
		return false
	}
	return true
}

// GetCacheDeviceState 取缓存中的值
func GetCacheDeviceState(sn string) (status int, lastTime *common.Time) {
	if global.GVA_REDIS == nil {
		return 0, nil
	}
	result, _ := global.GVA_REDIS.Get(context.Background(), CacheDeviceInfoKey(sn)).Result()
	if result == "" {
		return 0, nil
	}
	cacheInfo := CacheDeviceInfo{}
	err := json.Unmarshal([]byte(result), &cacheInfo)
	if err != nil {
		global.GVA_LOG.Error(err.Error())
		return 0, nil
	}
	return cacheInfo.Status, cacheInfo.LastTime
}