GtDataStore/app/cmd/events/internal/logic/handler/handler.go

package handler

import (
	"GtDataStore/app/cmd/events/internal/svc"
	"GtDataStore/app/model"
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"metawant.greentech.com.cn/gaoyagang/gt-common/rabbitMQ"
	"strconv"
	"time"
)

const (
	UF_BACKWASH = "EVENT:NOFITY:92:UF_BACKWASH"

	RABBIT_EXCHANGE_NAME = "gt.dc.event"
)

type (
	EventHandler struct {
		funcs    map[string]func(message []byte) error
		consumer *rabbitMQ.Consumer
		svcCtx   *svc.ServiceContext
	}
)

func NewEventHandler(ctx *svc.ServiceContext) (*EventHandler, error) {
	consumer, err := rabbitMQ.NewConsumer(rabbitMQ.Exchange{
		Name: RABBIT_EXCHANGE_NAME,
		Type: "fanout",
		Dns:  ctx.Config.RabbitMQ.Url,
	})

	if err != nil {
		return nil, err
	}

	eh := &EventHandler{
		funcs:    make(map[string]func(message []byte) error),
		consumer: consumer,
		svcCtx:   ctx,
	}

	return eh, nil
}

func (h *EventHandler) Start() {
	go h.consumer.Handler(UF_BACKWASH, h.adjustFilterCycle)
	fmt.Printf("listen event by: %s to uf.FilterEarly\n", UF_BACKWASH)

	select {}
}

func (h *EventHandler) adjustFilterCycle(message []byte) error {
	var entInfo multiEventInfo
	if err := json.Unmarshal(message, &entInfo); err != nil {
		return err
	}
	fmt.Printf("adjustFilterCycle Start")

	// 获得一个时间窗口中的许可, 如果获得失败, 则说明事件重复, 不处理  600的是因为 超滤膜反洗时间不会超过600秒
	if h.canExec(entInfo.ProjectId, entInfo.DeviceCode, "adjustFilterCycle", "", 600*time.Second) == false {
		fmt.Printf("adjustFilterCycle 不可重复执行\n")
		return nil
	}

	deviceInfo, err := h.getDeviceInfo(entInfo.ProjectId, entInfo.DeviceCode)
	if err != nil {
		return err
	}

	filterCycleItem, ok := deviceInfo.Items["filter_cycle"]
	if ok == false {
		return errors.New("filter_cycle not config")
	}
	stepItem, ok := deviceInfo.Items["step"]
	if ok == false {
		return errors.New("step not config")
	}

	filterCycleItemValue, ok := entInfo.NewValues[filterCycleItem.Item]
	if ok == false {
		return errors.New("filter_cycle value is empty")
	}

	stepItemValue, ok := entInfo.NewValues[stepItem.Item]

	filterCycle, err := strconv.ParseInt(filterCycleItemValue, 10, 64)
	step, err := strconv.ParseInt(stepItemValue, 10, 64)
	// 每进行一次反洗, 如果数据表中已经存在本周期的数据记录, 则adjust数值 +1
	// adjust意味着 自控系统与实际过滤周期数的差值
	if r, err := h.svcCtx.DcWorkingUf.FindLastByCycleAndStep(context.Background(), entInfo.ProjectId, entInfo.DeviceCode, filterCycle, step); err != nil || r == nil {
		// 没有查询到, 说明自控中该值已自增
		return nil
	} else {
		// 查询到了, 但可能是上一个CEB周期的数据, 也跳过
		// 判断是否为上一个周期的数据: 大于r.id的值, 并且存在着过滤数据
		if ls, _ := h.svcCtx.DcWorkingUf.FindForCycleAndStep(context.Background(), r.Id, entInfo.ProjectId, entInfo.DeviceCode, 0, step, 0, 1000, 1); len(ls) > 0 {
			return nil
		}
	}

	// 通过上面的判断, 得知自控系统的filterCycle值阻塞了, 需要调整
	key := fmt.Sprintf("events:adjust:%d:%s:%s:%s", entInfo.ProjectId, entInfo.DeviceCode, "filter_cycle", "")
	h.svcCtx.Cache.Incr(context.Background(), key)
	h.svcCtx.Cache.Expire(context.Background(), key, 86400*time.Second)

	return nil
}

func (h *EventHandler) canExec(projectId int64, deviceCode, opName, salt string, expire time.Duration) bool {
	key := fmt.Sprintf("events:handler:%d:%s:%s:%s", projectId, deviceCode, opName, salt)
	if intCmd := h.svcCtx.Cache.Incr(context.Background(), key); intCmd.Val() == 1 {
		_ = h.svcCtx.Cache.Expire(context.Background(), key, expire)
		return true
	} else {
		// 缓存续期
		_ = h.svcCtx.Cache.Expire(context.Background(), key, expire)
	}

	return false
}

func (h *EventHandler) getDeviceInfo(projectId int64, deviceCode string) (*model.DcDeviceBind, error) {
	return h.svcCtx.DcDeviceBind.FindOneByProjectIdDeviceCode(context.Background(), projectId, deviceCode)
}