iOS - 长链接Socket通信实现

备注：项目中需要放弃掉XMPP框架，自定义Socket长链接去进行通信的实现，方便管理、精简功能！记录笔记以供以后记忆！

一、工作注意点

    1.导入 CocoaAsyncSocket ；
    2.新建Model类，设置单例，定义各种成员方法暴露以供外用和自用<connect、login、logout、disconnect、destory等>；
    3.字节流设置 ：魔数<4字节> + 版本信息<1字节> + 序列化类型<1字节> + 指令<1字节> + body长度<4字节> + body内容；
    4.包头恒定为11字节，粘包拆包可以采用分隔符方式，也可以采用以字节流中的body长度+包头长度方式进行划分拆包；
    5.代理回调和webSocket区别不是很大<链接成功代理、链接失败代理、发送成功代理、接收消息代理>；
    6.发送消息方式：[_socket writeData:data withTimeout:-1 tag:1]
      拉取数据方式：[sock readDataWithTimeout:-1 tag:0];
    7.相对于webScoket，GCDAsyncSocket需要手动设置拉取数据才能从服务端获取数据<注意拉取数据的代码位置>；

二、核心代码

  /// 链接
- (BOOL)connect{

    self.isLogined = login_status_ing;
    self.isReconnect = YES;

    if (_socket.isConnected) {
        return NO;
    }

    if (!_socket) {
        _socket = [[GCDAsyncSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()];
    }

    NSError *error = nil;
//    [_socket connectToHost:@"ts.2uchat.cn" onPort:18089 error:&error];
    [_socket connectToHost:@"ip" onPort:端口 error:&error];//161.189.124.112 // 192.168.199.125

    if (error) {
        MSULog(@"__connect error:%@",error.userInfo);
        return NO;
    }

    return YES;
}

/// 登录
-(void)login{
    self.isReconnect = YES;

    if(_isLogined == login_status_yes)
        return;
    if (TU_MyTool.isLogin == NO || TU_MyTool.isKick == YES) {
        return;
    }
    if (![self connect]) {

    };
}

/// 退出
-(void)logout{

    if(!_isLogined)
        return;
    self.newMsgCount = 0;
    TU_MyTool.lastOfflineTime = [[NSDate date] timeIntervalSince1970];
    [self disconnect];
    [_roomPool deleteAll];

}

- (void)destory{
    if (!_socket.isConnected) {
    
        [self notify];
        self.isLogined = login_status_no;
    
        return;
    }

    [_socket disconnect];
}

#pragma mark - Socket Delegate
- (void)socket:(GCDAsyncSocket *)sock didConnectToHost:(NSString *)host     port:(uint16_t)port
{
    MSULog(@"Socket连接成功：%s",__func__);
    self.readBuf = [[NSMutableData alloc] init];
    [self doLogin];
    [self sendPing];
    [sock readDataWithTimeout:-1 tag:0];
}

-(void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(NSError *)err{
    if (err) {
        MSULog(@"连接失败--%@",err);
    }else{
        MSULog(@"正常断开");
    }
    [_socket disconnect];
    self.isLogined = login_status_no;

//    if (self.heartTimer) {
//         [self.heartTimer invalidate];
//         self.heartTimer = nil;
//     }

//    if ([sock.userData isEqualToString:[NSString stringWithFormat:@"%d",SOCKET_CONNECT_SERVER]])
//    {
//        //服务器掉线 重新连接
//        [self connectToServerWithCommand:@"battery"];
//    }else
//    {
//        return;
//    }
}

-(void)socket:(GCDAsyncSocket *)sock didWriteDataWithTag:(long)tag {
    MSULog(@"数据发送成功：%s",__func__);
    //发送完数据手动读取，-1不设置超时
}

- (void)socket:(GCDAsyncSocket *)sock didReadPartialDataOfLength:(NSUInteger)partialLength tag:(long)tag{
    MSULog(@"数据接收成功----%@",@"111111111111");

}

-(void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag {
    MSULog(@"数据接收成功----%@",[MSUSocketUtils hexStringFromData:data]);
//    NSString *receiverStr = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
//    NSRange range = [receiverStr rangeOfString:@"{"];
//    NSString *subStr = [receiverStr substringFromIndex:range.location];
//    NSDictionary *dic = [self dictionaryWithJsonString:subStr];
//    MSULog(@"接收到的数据----%@",dic);

//    MSULog(@"%@",[MSUSocketUtils hexStringFromData:data]);
//
//    NSData *moShuData = [data subdataWithRange:NSMakeRange(0, 4)];
//    MSULog(@"%@-----魔数：%@",moShuData,[MSUSocketUtils hexStringFromData:moShuData]);
//
//    NSData *versionData = [data subdataWithRange:NSMakeRange(4, 1)];
//    MSULog(@"%@-----版本：%hhu",versionData,[MSUSocketUtils uint8FromBytes:versionData]);
//
//    NSData *typeData = [data subdataWithRange:NSMakeRange(5, 1)];
//    MSULog(@"%@-----序列化类型：%hhu",typeData,[MSUSocketUtils uint8FromBytes:typeData]);

    ///此处采用以字节流中的body长度+包头长度方式进行划分拆包
    //将数据存入缓存区
    [self.readBuf appendData:data];
    while (self.readBuf.length > 11) {
        NSData *lenthData = [self.readBuf subdataWithRange:NSMakeRange(7, 4)];
        NSUInteger allLength = [MSUSocketUtils uint32FromBytes:lenthData] + 11;///body长度+包头长度
        if (self.readBuf.length >= allLength) {
            NSMutableData *msgData = [[self.readBuf subdataWithRange:NSMakeRange(0, allLength)] mutableCopy];
            [self handelData:msgData withSocket:sock];
            _readBuf = [NSMutableData dataWithData:[_readBuf subdataWithRange:NSMakeRange(allLength, _readBuf.length - allLength)]];
        } else {
            //缓存区内数据包不是完整的，再次从服务器获取数据，中断while循环
            [_socket readDataWithTimeout:-1 tag:0];
            break;
        }
    }

    [sock readDataWithTimeout:-1 tag:0];
}


- (void)handelData:(NSData *)data withSocket:(GCDAsyncSocket *)sock{
        NSData *commandData = [data subdataWithRange:NSMakeRange(6, 1)];
        NSString *commandStr = [MSUSocketUtils hexStringFromData:commandData];
    
//        NSData *lenthData = [data subdataWithRange:NSMakeRange(7, 4)];
//        MSULog(@"字节流内容%@ ----body长度%u-----指令：%@",    [MSUSocketUtils hexStringFromData:data],[MSUSocketUtils uint32FromBytes:lenthData],commandStr);

        NSData *bodyData = [data subdataWithRange:NSMakeRange(11, data.length - 11)];
        NSString *deStr = [MSUAesTools msu_aes_decrytGetBaseStrWihData:bodyData key:nil];
        NSDictionary *resultDic = [MSUStringTools dictionaryWithJsonString:deStr];
        MSULog(@"-----body内容：%@",resultDic);

      ///处理逻辑 略
}