fusenapi/server/websocket/internal/logic/ws_reuse_last_connect.go

package logic

//复用websocket连接标识
import (
	"encoding/json"
	"fmt"
	"fusenapi/constants"
	"fusenapi/utils/encryption_decryption"
	"github.com/zeromicro/go-zero/core/logx"
)

// 刷新重连请求恢复上次连接的标识
func (w *wsConnectItem) reuseLastConnect(data []byte) {
	logx.Info("收到请求恢复上次连接标识数据:", string(data))
	var clientId string
	if err := json.Unmarshal(data, &clientId); err != nil {
		logx.Error(" invalid format of client id :", clientId)
		w.sendToOutChan(w.respondDataFormat(constants.WEBSOCKET_REQUEST_RESUME_LAST_CONNECT_ERR, "invalid format of client id"))
		return
	}
	//解密
	decryptionClientId, err := encryption_decryption.CBCDecrypt(clientId)
	if err != nil {
		w.sendToOutChan(w.respondDataFormat(constants.WEBSOCKET_REQUEST_RESUME_LAST_CONNECT_ERR, "invalid client id"))
		return
	}
	lendecryptionClientId := len(decryptionClientId)
	//合成client后缀,不是同个后缀的不能复用
	userPart := getUserJoinPart(w.userId, w.guestId)
	lenUserPart := len(userPart)
	if lendecryptionClientId <= lenUserPart {
		w.sendToOutChan(w.respondDataFormat(constants.WEBSOCKET_REQUEST_RESUME_LAST_CONNECT_ERR, "length of client id is to short"))
		return
	}
	//尾部不同不能复用
	if decryptionClientId[lendecryptionClientId-lenUserPart:] != userPart {
		w.sendToOutChan(w.respondDataFormat(constants.WEBSOCKET_REQUEST_RESUME_LAST_CONNECT_ERR, "the client id is not belong you before"))
		return
	}
	publicMutex.Lock()
	defer publicMutex.Unlock()
	//存在是不能给他申请重新绑定
	if v, ok := mapConnPool.Load(clientId); ok {
		obj, ok := v.(wsConnectItem)
		if !ok {
			logx.Error("连接断言失败")
		}
		//是当前自己占用
		if obj.uniqueId == w.uniqueId {
			//重新绑定
			w.uniqueId = clientId
			rsp := w.respondDataFormat(constants.WEBSOCKET_CONNECT_SUCCESS, clientId)
			w.sendToOutChan(rsp)
			return
		} else {
			rsp := w.respondDataFormat(constants.WEBSOCKET_REQUEST_RESUME_LAST_CONNECT_ERR, "id has bound by other connect ")
			w.sendToOutChan(rsp)
			return
		}
	}
	//重新绑定
	w.uniqueId = clientId
	rsp := w.respondDataFormat(constants.WEBSOCKET_CONNECT_SUCCESS, clientId)
	w.sendToOutChan(rsp)
	return
}

// 获取用户拼接部分(复用标识用到)
func getUserJoinPart(userId, guestId int64) string {
	return fmt.Sprintf("|_%d_%d_|", userId, guestId)
}