记一次golang的实践

之前做过一个深交所股票数据的接存储软件，消息的协议是这样。

协议文档在这  https://wenku.baidu.com/view/d102cd0b4a73f242336c1eb91a37f111f1850df2.html

由于socket接受来的数据会出现粘包或者半包的情况。所以要进行拆包处理代码是这样的，但是无论网络状态是否稳定都会出现丢包的情况。

  private RecMessage TryReadAmessage(ref byte[] bytes)
        {
            if (bytes.Length < )
                return null;
            var msgType = NetworkBitConverter.ToInt32(bytes, );
            if (messageTypes.Contains(msgType))
            {

                var msgLength = NetworkBitConverter.ToInt32(bytes, );
                if (msgLength >=  && msgLength < )
                {
                    if (bytes.Length < (msgLength + ))
                        return null;

                    var outputByte = new byte[ + msgLength];
                    Array.Copy(bytes, outputByte, msgLength + );
                    bytes = bytes.Removebytes(msgLength + );
                    var chkbyte = new byte[];
                    Array.Copy(outputByte, msgLength + , chkbyte, , );
                    if (!GetBytesFomObj.CheckSum(chkbyte, outputByte)) return null;

                    return new RecMessage
                    {
                        MessageType = msgType,
                        MessageLenght = msgLength,
                        MessageContent = outputByte.Removebytes()
                    };
                }
                else
                    bytes = bytes.Removebytes();
            }
            else
                bytes = bytes.Removebytes();
            return null;
        }

后来用了supersocket框架拆包，效果不错，基本没有发现错误包的情况。看代码

  public class ClientBinaryFilter : FixedHeaderReceiveFilter<RecMessage>
     {
         /// <summary>
         /// 所有消息类型
         /// </summary>
         private readonly int[] _messageTypes = new int[]
         {   ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,
             ,

         };
         public ClientBinaryFilter() : base()
         {

         }
         private int key;
         private int datalength;
         protected override int GetBodyLengthFromHeader(IBufferStream bufferStream, int length)
         {
             key = bufferStream.ReadInt32(false);
             datalength = bufferStream.ReadInt32(false);
             return datalength + ;
         }

         public override RecMessage ResolvePackage(IBufferStream bufferStream)
         {
             var buffer = new byte[datalength + ];
             bufferStream.Skip().Read(buffer, , datalength + );
             return new RecMessage
             {
                 MessageType = key,
                 MessageLenght = datalength,
                 MessageContent = buffer
             };
         }
     }

后来学习了golang语言，感觉非常适合做这种实时性很高的软件。由于逻辑不是特别复杂，没有用到所有的golang的特性，知识点有：net(socket),goruntime,channel(缓冲)，数组切片slice，互斥锁sync.Mutex，redigo(redis)，ffjson(序列化与反序列化)

核心的代码在这里

 //socket接受函数
 func handMsgChannel(con net.Conn) {
     con.Write(SendLogOn())
     go sendHeartBt(con)
     var unCompleteBytes []byte
     for {
         //startTime := time.Now()
         buffer := make([]byte, )
         readLength, err := con.Read(buffer)
         CheckError(err, con)
         if readLength >  {
             var readBuf []byte = buffer[:readLength]
             //获取上次为解析的半包并装载到此次循环中解析
             if len(unCompleteBytes) !=  {
                 readBuf = lib.BytesCopy(unCompleteBytes, readBuf)
             }
             readMessageChannel(&readBuf) //拆包分解，并把半包数据留在下次循环处理
             unCompleteBytes = readBuf
             //endTime := time.Since(startTime)
             //fmt.Println("读取并数据处理时间: ", endTime)
         }
     }
 }

 //利用channel读取并传入channel
 func readMessageChannel(input *[]byte) {
     //var output []BaseMsgModel
     for {
         byteArray := *input
         //头+长度+校验 最小12个字节，不足跳出
         if len(byteArray) <  {
             break
         }
         mt := lib.BytesToInt32(byteArray[:])
         //获取数据头
         if lib.Contain(mt, MsgTypes) {
             ml := lib.BytesToInt32(byteArray[:])
             //数据长度
             if ml >=  && ml <  {
                 if len(byteArray) < +int(ml) {
                     break
                 }
                 //获取报文content
                 mc := byteArray[ : +int(ml)]
                 sum := lib.BytesToInt32(mc[len(mc)- : len(mc)])
                 checksum := lib.CheckSum(byteArray[ : +int(ml)])
                 //检查校验
                 if checksum == sum {
                     model := &BaseMsgModel{
                         mt,
                         ml,
                         mc,
                     }
                     chmsg <- model
                     *input = byteArray[+int(ml):]
                 } else {
                     *input = byteArray[+int(ml):]
                     fmt.Println("错误数据")
                 }
             } else {
                 //错误长度移除
                 *input = byteArray[:]
                 fmt.Println("错误长度")
             }
         } else {
             //错误头部移除
             *input = byteArray[:]
             fmt.Println("错误头")
         }
     }
 }

 //分发存储channel中数据
 func translateMsgChannel() {
     for {
         item := <-chmsg
         //fmt.Print("数据类型", msgs.MsgType, "数据长度", msgs.MsgLength, msgs.MsgContent, "\r\n")
         switch item.MsgType {
         case :
             msg.Save300111(item.MsgContent)
             systemParams.Params.Lock()
             systemParams.msg300111Length++
             systemParams.Params.Unlock()
             break
         case :
             msg.Save309011(item.MsgContent)
             systemParams.Params.Lock()
             systemParams.msg309011Length++
             systemParams.Params.Unlock()
             break
         default:
             break
         }
         systemParams.Params.Lock()
         systemParams.RecLength++
         systemParams.Params.Unlock()
     }
 }

经测试后不禁感叹golang真是黑科技，.net的代码内存会达到50M以上，CPU10%左右(I5 4核4线程)

golang呢10M左右 CPU 0.5%~1%，golang。。。牛啊！

代码在这  https://gitee.com/siming.liu/golang_stock