利用RHSocketKit构建自定义协议通信

利用RHSocketKit构建自定义协议通信

在网络传输中，tcp/ip协议只是网络的基础，分别属于传输层和网络层。我们各种应用之间的通信需要依赖各种各样的协议，是建立在tcp/ip之上的，比如典型的http协议。

在开发过程中，一般我们制定的协议需要两个部分，header和content。

1-header：协议头部，放置一些meta信息。

2-content：应用之间交互的信息主体。

例如：分隔符delimiter－2个字节｜数据包类型type－2个字节｜长度length（不含包头长度）－4个字节｜数据信息主体content－length个子节

其中delimiter，type，length就是header信息，content就是交互的主体。

我们来利用RHSocketKit构造一个数据包对象。

#import "RHSocketPacketContext.h"

@interface RHSocketCustomRequest : RHSocketPacketRequest
//这里，我们把content数据放在夫类的object变量中。
//length可以通过object数据直接获得，不再申明额外的变量。
@property (nonatomic, assign) int16_t fenGeFu;
@property (nonatomic, assign) int16_t dataType;

@end

数据包已经创建好了，那么我们在RHSocketKit中如何去对这种自定义的协议编码（Encode）呢？

定义编码协议RHSocketEncoderProtocol和解码协议RHSocketDecoderProtocol。

RHSocketCustom0330Encoder：编码器，将发送包的数据从一种格式转换成二进制数组。

RHSocketCustom0330Decoder：解码器，将接收包的二进制数组转换成可读的变量数据。

RHSocketCustom0330Encoder文件

#import <Foundation/Foundation.h>
#import "RHSocketCodecProtocol.h"

@interface RHSocketCustom0330Encoder : NSObject <RHSocketEncoderProtocol>

@end

#import "RHSocketCustom0330Encoder.h"
#import "RHSocketException.h"
#import "RHSocketUtils.h"
#import "RHSocketCustomRequest.h"

@implementation RHSocketCustom0330Encoder

- (void)encode:(id<RHUpstreamPacket>)upstreamPacket output:(id<RHSocketEncoderOutputProtocol>)output
{
    id object = [upstreamPacket object];
    if (![object isKindOfClass:[NSData class]]) {
        [RHSocketException raiseWithReason:@"[Encode] object should be NSData ..."];
        return;
    }
    
    NSData *data = object;
    if (data.length == 0) {
        return;
    }//
    
    RHSocketCustomRequest *req = (RHSocketCustomRequest *)upstreamPacket;
    NSUInteger dataLen = data.length;
    //<strong><span style="color:#ff0000;">注意这里，按照协议的描述，顺序把数值转成二进制填充到对应的位置，然后output输出</span></strong>
    NSMutableData *sendData = [[NSMutableData alloc] init];
    //分隔符 2个字节
    [sendData appendData:[RHSocketUtils bytesFromUInt16:req.fenGeFu]];
    //数据包类型 2个字节
    [sendData appendData:[RHSocketUtils bytesFromUInt16:req.dataType]];
    //长度（不含包头长度） 4个字节
    [sendData appendData:[RHSocketUtils bytesFromUInt32:(uint32_t)dataLen]];
    //数据包 dataLen个字节
    [sendData appendData:data];
    
    NSTimeInterval timeout = [upstreamPacket timeout];
    
    RHSocketLog(@"timeout: %f, sendData: %@", timeout, sendData);
    [output didEncode:sendData timeout:timeout];
}

@end

RHSocketCustom0330Decoder文件

#import <Foundation/Foundation.h>
#import "RHSocketCodecProtocol.h"

@interface RHSocketCustom0330Decoder : NSObject <RHSocketDecoderProtocol>

@end


#import "RHSocketCustom0330Decoder.h"
#import "RHSocketException.h"
#import "RHSocketUtils.h"
#import "RHSocketCustomResponse.h"

@interface RHSocketCustom0330Decoder ()
{
    NSUInteger _countOfLengthByte;
}

@end

@implementation RHSocketCustom0330Decoder

- (instancetype)init
{
    if (self = [super init]) {
        _countOfLengthByte = 8;
    }
    return self;
}

- (NSInteger)decode:(id<RHDownstreamPacket>)downstreamPacket output:(id<RHSocketDecoderOutputProtocol>)output
{
    id object = [downstreamPacket object];
    if (![object isKindOfClass:[NSData class]]) {
        [RHSocketException raiseWithReason:@"[Decode] object should be NSData ..."];
        return -1;
    }
    
    NSData *downstreamData = object;
    NSUInteger headIndex = 0;
    
    while (downstreamData && downstreamData.length - headIndex >= _countOfLengthByte) {
        NSData *headData = [downstreamData subdataWithRange:NSMakeRange(headIndex, _countOfLengthByte)];
        //去第4个字节开始的4个字节长度
        NSData *lenData = [headData subdataWithRange:NSMakeRange(4, 4)];
        //长度字节数据，可能存在高低位互换，通过数值转换工具处理
        NSUInteger frameLen = [RHSocketUtils uint32FromBytes:lenData];
        
        //剩余数据，不是完整的数据包，则break继续读取等待
        if (downstreamData.length - headIndex < _countOfLengthByte + frameLen) {
            break;
        }
        //数据包(长度＋内容)
        NSData *frameData = [downstreamData subdataWithRange:NSMakeRange(headIndex, _countOfLengthByte + frameLen)];
        
        //去除数据长度后的数据内容
        RHSocketCustomResponse *rsp = [[RHSocketCustomResponse alloc] init];
        rsp.fenGeFu = [RHSocketUtils uint16FromBytes:[headData subdataWithRange:NSMakeRange(0, 2)]];
        rsp.dataType = [RHSocketUtils uint16FromBytes:[headData subdataWithRange:NSMakeRange(2, 2)]];
        rsp.object = [frameData subdataWithRange:NSMakeRange(_countOfLengthByte, frameLen)];
        
        [output didDecode:rsp];
        
        //调整已经解码数据
        headIndex += frameData.length;
    }//while
    return headIndex;
}

@end

codec组件已经准备就绪，接下来我们增加调用控制。RHSocketKit中已经提供了一个单例的service，已经提取和封装了可重用代码。只需要重载编解码器就可以了。

    //这里的服务器对应RHSocketServerDemo，连接之前，需要运行RHSocketServerDemo开启服务端监听。
    //RHSocketServerDemo服务端只是返回数据，收到的数据是原封不动的，用来模拟发送给客户端的数据。
    NSString *host = @"127.0.0.1";
    int port = 20162;
    
    //变长编解码。包体＝包头（包体的长度）＋包体数据
    RHSocketCustom0330Encoder *encoder = [[RHSocketCustom0330Encoder alloc] init];
    RHSocketCustom0330Decoder *decoder = [[RHSocketCustom0330Decoder alloc] init];
    
    [RHSocketService sharedInstance].encoder = encoder;
    [RHSocketService sharedInstance].decoder = decoder;
    
    [[RHSocketService sharedInstance] startServiceWithHost:host port:port];

<span style="font-size:18px;">编写一个服务端对这个通信协议作测试，我这里使用简单的echo服务器测试。代码很简单，我就不贴了。</span>

<span style="font-size:18px;">可以直接查看源码<a target=_blank href="https://github.com/zhu410289616/RHSocketKit/tree/master/RHSocketServerDemo">RHSocketServerDemo</a>。</span>

客户端的过程是，先连接服务器，然后发送数据包。然后服务端返回相同的数据包给客户端，客户端做解码，然后输出展示。

测试代码如下：

#import "ViewController.h"
#import "RHSocketService.h"

#import "RHSocketCustom0330Encoder.h"
#import "RHSocketCustom0330Decoder.h"

#import "RHSocketCustomRequest.h"
#import "RHSocketCustomResponse.h"

@interface ViewController ()
{
    UIButton *_serviceTestButton;
}

@end

@implementation ViewController

- (void)loadView
{
    [super loadView];
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(detectSocketServiceState:) name:kNotificationSocketServiceState object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(detectSocketPacketResponse:) name:kNotificationSocketPacketResponse object:nil];
}

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    _serviceTestButton = [UIButton buttonWithType:UIButtonTypeCustom];
    _serviceTestButton.frame = CGRectMake(20, 120, 250, 40);
    _serviceTestButton.layer.borderColor = [UIColor blackColor].CGColor;
    _serviceTestButton.layer.borderWidth = 0.5;
    _serviceTestButton.layer.masksToBounds = YES;
    [_serviceTestButton setTitleColor:[UIColor darkGrayColor] forState:UIControlStateNormal];
    [_serviceTestButton setTitle:@"Test Custom Codec" forState:UIControlStateNormal];
    [_serviceTestButton addTarget:self action:@selector(doTestServiceButtonAction) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:_serviceTestButton];
    
}

- (void)doTestServiceButtonAction
{
    //方便多次观察，先停止之前的连接
    [[RHSocketService sharedInstance] stopService];
    
    //这里的服务器对应RHSocketServerDemo，连接之前，需要运行RHSocketServerDemo开启服务端监听。
    //RHSocketServerDemo服务端只是返回数据，收到的数据是原封不动的，用来模拟发送给客户端的数据。
    NSString *host = @"127.0.0.1";
    int port = 20162;
    
    //变长编解码。包体＝包头（包体的长度）＋包体数据
    RHSocketCustom0330Encoder *encoder = [[RHSocketCustom0330Encoder alloc] init];
    RHSocketCustom0330Decoder *decoder = [[RHSocketCustom0330Decoder alloc] init];
    
    [RHSocketService sharedInstance].encoder = encoder;
    [RHSocketService sharedInstance].decoder = decoder;
    
    [[RHSocketService sharedInstance] startServiceWithHost:host port:port];
}

- (void)detectSocketServiceState:(NSNotification *)notif
{
    //NSDictionary *userInfo = @{@"host":host, @"port":@(port), @"isRunning":@(_isRunning)};
    //对应的连接ip和状态数据。_isRunning为YES是连接成功。
    //没有心跳超时后会自动断开。
    NSLog(@"detectSocketServiceState: %@", notif);
    
    id state = notif.object;
    if (state && [state boolValue]) {
        //连接成功后，发送数据包
        RHSocketCustomRequest *req = [[RHSocketCustomRequest alloc] init];
        req.fenGeFu = 0x24;
        req.dataType = 1234;
        req.object = [@"变长编码器和解码器测试数据包1" dataUsingEncoding:NSUTF8StringEncoding];
        [[NSNotificationCenter defaultCenter] postNotificationName:kNotificationSocketPacketRequest object:req];
        
        req = [[RHSocketCustomRequest alloc] init];
        req.fenGeFu = 0x24;
        req.dataType = 12;
        req.object = [@"变长编码器和解码器测试数据包20" dataUsingEncoding:NSUTF8StringEncoding];
        [[NSNotificationCenter defaultCenter] postNotificationName:kNotificationSocketPacketRequest object:req];
        
        req = [[RHSocketCustomRequest alloc] init];
        req.fenGeFu = 0x24;
        req.dataType = 0;
        req.object = [@"变长编码器和解码器测试数据包300" dataUsingEncoding:NSUTF8StringEncoding];
        [[NSNotificationCenter defaultCenter] postNotificationName:kNotificationSocketPacketRequest object:req];
        
    } else {
        //
    }//if
}

- (void)detectSocketPacketResponse:(NSNotification *)notif
{
    NSLog(@"detectSocketPacketResponse: %@", notif);
    
    //这里结果，记得观察打印的内容
    NSDictionary *userInfo = notif.userInfo;
    RHSocketCustomResponse *rsp = userInfo[@"RHSocketPacket"];
    NSLog(@"detectSocketPacketResponse data: %@", [rsp object]);
    NSLog(@"detectSocketPacketResponse string: %@", [[NSString alloc] initWithData:[rsp object] encoding:NSUTF8StringEncoding]);
}

源码RHSocketCustomCodecDemo已经上传到github中，可以自行下载。

（demo中是通过pod引入RHSocketKit库的，已经包含了Podfile文件，pod install后就可以正常运行）

－－－－－－－－－－－－－－－－－－－－－－－－

转载请注明出处，谢谢

email: [email protected]

qq: 410289616

qq群：330585393

利用RHSocketKit构建自定义协议通信

不翻牆快速下載CocoaPods索引的方法

CocoaAsyncSocket 網絡通信使用之http協議測試（三）

利用RHSocketKit構建自定義協議通信

CocoaAsyncSocket網絡通信使用之數據編碼和解碼（二）

MQTT協議實現（一）

Mac下配置sublime實現LaTeX

https://yachay.unat.edu.pe/blog/index.php?comment_area=format_blog&comment_component=blog&comment_co

linux以太網驅動總結