iOS使用socket实现聊天功能

关于GCDAsyncSocket实现即时通讯功能
客户端需要做的：
1、连接服务器，连接socket，发送心跳
2、编码数据包，发送消息给服务器
3、接收处理服务器返回的消息
4、提供手动断联socket方法，在需要的地方调用
5、socket非手动断联，重新请求连接
服务端需要做的:
1、用户心跳的维持和刷新
2、用户的调用
3、数据包的拆解和分发等

新建socket管理类BLSocketManager
.h文件

@interface BLSocketManager : NSObject

+ (instancetype)sharedManager;

- (void)disConnectClearTime;

//收到消息回调
@property (nonatomic, copy) void(^getChatData)(id result);//回调根据自身需求返回，此处为了便于查看，暂时使用id类型

//发送确认消息
- (void)sendSureDatawithFriend:(int)friendid;

@end

.m文件

#import "BLSocketManager.h"
#import <GCDAsyncSocket.h>
#import "NSMutableData+BLMutableData.h"//进行数据的编码和解码过程

@interface BLSocketManager ()<GCDAsyncSocketDelegate>

@property (strong, nonatomic) GCDAsyncSocket *gcdSocket;
@property (nonatomic, strong) NSTimer *timer;
@property (nonatomic, assign) BOOL disconnect;
@property (nonatomic, strong) NSString *hostUrl;
@property (nonatomic, strong) NSString *hostCode;

@end
static BLSocketManager *userInfo = nil;
@implementation BLSocketManager
+ (instancetype)sharedManager {
    static dispatch_once_t once;
    dispatch_once(&once, ^{
        userInfo = [[BLSocketManager alloc]init];
    });
    return userInfo;
}
//间隔5s发一次心跳，可根据实际需求自己调节
-(NSTimer *)timer{
    if (!_timer) {
        __weak typeof(self)weakSelf = self;
        if (@available(iOS 10.0, *)) {
            _timer = [NSTimer timerWithTimeInterval:5 repeats:true block:^(NSTimer * _Nonnull timer) {
                [weakSelf heartBeat];
            }];
        } else {
            _timer = [NSTimer scheduledTimerWithTimeInterval:5 target:self selector:@selector(heartBeat) userInfo:nil repeats:true];
        }
    }
    return _timer;
}
//初始化socket，设置代理
-(GCDAsyncSocket *)gcdSocket{
    if (!_gcdSocket) {
        _gcdSocket = [[GCDAsyncSocket alloc]initWithDelegate:self delegateQueue:dispatch_get_main_queue()];
    }
    return _gcdSocket;
}
//请求后台接口获取ip和端口，开始连接tcp
- (void)addConnectSendHeart{
    NSString *urlString = @"https://im/route/selectServer";
    NSMutableDictionary *dict = [NSMutableDictionary dictionary];
    dict[@"userId"] = @"";
    dict[@"deviceId"] = @"";
//    [MyRequest call:HTTPMethod_POST postWithUrl:urlString userDic:dict token:[BaseUserManager shareUser].token?[BaseUserManager shareUser].token:@"" Callback:^(BOOL isSuccess, NSDictionary *result) {
//        if (isSuccess) {
//            NSDictionary *datadic = result[@"data"];
//            self.hostUrl = datadic[@"ip"];
//            self.hostCode = datadic[@"serverPort"];
//            [self startSocketConnect];
//        }else{
//            [SVProgressHUD showAutoInfo:@"IM服务器连接失败"];
//        }
//    }];
    
}

//开始连接
- (void)startSocketConnect{
    [self.gcdSocket connectToHost:self.hostUrl onPort:[self.hostCode intValue] error:nil];
}

#pragma mark - GCDAsyncSocketDelegate

//当套接字连接并准备好读写时调用，添加timer到runLoop中定时发心跳，LoginMsgRequest为自定义数据类型，可根据自身需求定义协议算法
//写入数据到套接字，完成后调用读取数据didReadData的代理方法
- (void)socket:(GCDAsyncSocket *)sock didConnectToHost:(NSString *)host port:(uint16_t)port {
    //读取socket上第一个可用的字节，如果超时值为负数，读操作将不会使用超时值
    [self.gcdSocket readDataWithTimeout:-1 tag:0];
    [[NSRunLoop currentRunLoop] addTimer:self.timer forMode:NSRunLoopCommonModes];
    [self heartBeat];
    NSData *yourdata = [NSData data];
    //可将包含userid、deviceid、token和消息类型(code)的数据转化为data，然后按照协商好的方式进行编码
    NSMutableData *temData = [NSMutableData encodeSocketProtoBufWithData:yourdata andCode:3];
    [self.gcdSocket writeData:temData withTimeout:-1 tag:0];
}
//当套接字断开连接时调用
- (void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(nullable NSError *)err {
    //判断是否是手动断联，disconnect标记为手动断开socket
    if (self.disconnect) {
        
    }else{
        if (err) {
            if (self.hostUrl) {
                [self addConnectSendHeart];
            }
        }
    }
}
//当套接字完成读取请求数据时调用，可根据和后台定义的数据传输格式读取想获得的数据
- (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag {
    [self.gcdSocket readDataWithTimeout:-1 tag:0];
    __weak typeof(self)weakSelf = self;
    [NSMutableData decodeSocketProtoBufData:data backContent:^(int procode, NSData * _Nonnull contentData) {
        [weakSelf backChatMessageContentData:contentData proCode:procode];
    }];
}
//前端后台协商的数据返回类型及处理
- (void)backChatMessageContentData:(NSData *)contentData proCode:(int)procode{
    //procode为后台定义的消息类型，可根据code进行不同消息处理
     if (procode == 11) {
         //聊天消息
//        DeliveryChatMsgRequest *requst = [DeliveryChatMsgRequest parseFromData:contentData error:nil];
         //收到消息后的回调
         if (self.getChatData) {
//             self.getChatData(requst.chatMsg);
             self.getChatData(contentData);
         }
         //给后台发送确认消息
        NSData *yourdata = [NSData data];
        NSMutableData *temData = [NSMutableData encodeSocketProtoBufWithData:yourdata andCode:5];
        [self.gcdSocket writeData:temData withTimeout:-1 tag:0];
    }else if (procode == 13){
        //通知消息
    }else if (procode == 5){
       
    }
}
//发送确认消息,用于消息列表点击查看时调用，区分已读和未读消息
- (void)sendSureDatawithFriend:(int)friendid{
    NSData *yourdata = [NSData data];
    NSMutableData *temData = [NSMutableData encodeSocketProtoBufWithData:yourdata andCode:5];
    [self.gcdSocket writeData:temData withTimeout:-1 tag:0];
}

//将"ping"和code按和后台协商的传输格式进行传输，发送心跳
- (void)heartBeat {
//    HeartbeatMsgRequest *beatMsg = [[HeartbeatMsgRequest alloc]init];
//    beatMsg.msg = @"ping";
    NSData *yourData = [NSData data];
    NSMutableData *temData = [NSMutableData encodeSocketProtoBufWithData:yourData andCode:1];
    [self.gcdSocket writeData:temData withTimeout:-1 tag:0];
}
//当套接字完成请求数据时调用，如果有错误则不调用
- (void)socket:(GCDAsyncSocket *)sock didWriteDataWithTag:(long)tag{
    [sock readDataWithTimeout:-1 tag:tag];
}
-(void)disConnectClearTime{
    if (self.timer) {
        [self.timer invalidate];
        self.timer = nil;
    }
    self.disconnect = true;
    [self.gcdSocket disconnect];
}


@end