最近项目使用中要改造redis客户端,看了下文档,总结分享一下。

阅读目录:
  1. 协议规范
  2. 基础通信
  3. 状态命令
  4. set、get命令
  5. 管道、事务
  6. 总结

协议规范

redis允许客户端以TCP方式连接,默认6379端口。传输数据都以\r\n结尾。

请求格式

*<number of arguments>\r\n$<number of bytes of argument 1>\r\n<argument data>\r\n

例:*1\r\n$4\r\nINFO\r\n

响应格式

1:简单字符串,非二进制安全字符串,一般是状态回复。  +开头,例:+OK\r\n 

2: 错误信息。          -开头, 例:-ERR unknown command 'mush'\r\n

3: 整型数字。                            :开头, 例::1\r\n

4:大块回复值,最大512M。           $开头+数据长度。 例:$4\r\mush\r\n

5:多条回复。                           *开头, 例:*2\r\n$3\r\nfoo\r\n$3\r\nbar\r\n

基础通信

定义配置类:

public class Configuration
{
public string Host { get; set; }
public int Port { get; set; }
/// <summary>
/// Socket 是否正在使用 Nagle 算法。
/// </summary>
public bool NoDelaySocket { get; set; }
 
public Configuration()
{
Host = "localhost";
Port = 6379;
NoDelaySocket = false;
}
}

实现socket连接:

c# redis操作 c# 连接redis_redis

</span><span >public</span><span > RedisBaseClient(Configuration config)
    {
        configuration </span>=<span > config;
    }

    </span><span >public</span><span > RedisBaseClient()
        : </span><span >this</span>(<span >new</span><span > Configuration())
    {
    }

    </span><span >public</span> <span >void</span><span > Connect()
    {
        </span><span >if</span> (socket != <span >null</span> &&<span > socket.Connected)
            </span><span >return</span><span >;
        socket </span>= <span >new</span><span > Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
        {
            NoDelay </span>=<span > configuration.NoDelaySocket
        };
        socket.Connect(configuration.Host, configuration.Port);
        </span><span >if</span><span > (socket.Connected)
            </span><span >return</span><span >;
        Close();
    }

    </span><span style="color: rgba(128, 128, 128, 1)">///</span> <span style="color: rgba(128, 128, 128, 1)"><summary></span>
    <span style="color: rgba(128, 128, 128, 1)">///</span><span > 关闭client
    </span><span style="color: rgba(128, 128, 128, 1)">///</span> <span style="color: rgba(128, 128, 128, 1)"></summary></span>
    <span >public</span> <span >void</span><span > Close()
    {
        socket.Disconnect(</span><span >false</span><span >);
        socket.Close();
    }
}</span></pre>

调用:

RedisBaseClient redis = new RedisBaseClient();
redis.Connect();

服务端成功响应:

c# redis操作 c# 连接redis_.net_02

  

状态命令

定义Redis命令枚举:

c# redis操作 c# 连接redis_c#_03

public enum RedisCommand
    {
        GET, //获取一个key的值
        INFO, //Redis信息。  
        SET, //添加一个值
        EXPIRE, //设置过期时间
        MULTI, //标记一个事务块开始
        EXEC, //执行所有 MULTI 之后发的命令
    }

c# redis操作 c# 连接redis_.net_04

发送命令构建:

c# redis操作 c# 连接redis_.net_05

</span><span >var</span> sb = <span >new</span><span > StringBuilder();
        sb.AppendFormat(headstr, args.Length </span>+ <span >1</span><span >);

        </span><span >var</span> cmd =<span > command.ToString();
        sb.AppendFormat(bulkstr, cmd.Length, cmd);

        </span><span >foreach</span> (<span >var</span> arg <span >in</span><span > args)
        {
            sb.AppendFormat(bulkstr, arg.Length, arg);
        }
        </span><span >byte</span>[] c =<span > Encoding.UTF8.GetBytes(sb.ToString());
        </span><span >try</span><span >
        {
            Connect();
            socket.Send(c);

            socket.Receive(ReceiveBuffer);
            Close();
            </span><span >return</span><span > ReadData();
        }
        </span><span >catch</span><span > (SocketException e)
        {
            Close();
        }
        </span><span >return</span> <span >null</span><span >;
    }

c# redis操作 c# 连接redis_c# redis操作_06

 调用:

private void button1_Click(object sender, EventArgs e)
{
RedisBaseClient redis = new RedisBaseClient();
var result = redis.SendCommand(RedisCommand.INFO);
richTextBox1.Text = result;
}

输出响应,其$937是数据包的长度。

 

c# redis操作 c# 连接redis_c# redis操作_07

set、get命令

调用:

c# redis操作 c# 连接redis_客户端_08

private void button2_Click(object sender, EventArgs e)
        {
            RedisBaseClient redis = new RedisBaseClient();
            var result = redis.SendCommand(RedisCommand.SET, "msg", "testvalue");
            richTextBox1.Text = result.ToString();
        }
        private void button3_Click(object sender, EventArgs e)
        {
            RedisBaseClient redis = new RedisBaseClient();
            var result = redis.SendCommand(RedisCommand.GET, "msg");
            richTextBox1.Text = result.ToString();
        }

c# redis操作 c# 连接redis_.net_09

输出

c# redis操作 c# 连接redis_c#_10

c# redis操作 c# 连接redis_.net_11

管道、事务

的MULTI,EXEC命令,原子操作。管道就是发送命令(无需等上次命令回复),进入命令队列,然后多条命令一次执行,并返回客户端结果。 

,其实是set、expire 2个命令。

c# redis操作 c# 连接redis_.net_12

</span><span >var</span> sb = <span >new</span><span > StringBuilder();
        sb.AppendFormat(headstr, args.Length </span>+ <span >1</span><span >);

        </span><span >var</span> cmd =<span > command.ToString();
        sb.AppendFormat(bulkstr, cmd.Length, cmd);

        </span><span >foreach</span> (<span >var</span> arg <span >in</span><span > args)
        {
            sb.AppendFormat(bulkstr, arg.Length, arg);
        }
        </span><span >byte</span>[] c =<span > Encoding.UTF8.GetBytes(sb.ToString());
        </span><span >try</span><span >
        {
            Connect();
            socket.Send(c);
            
            socket.Receive(ReceiveBuffer);
            </span><span >if</span> (!<span >isPipeline)
            {
                Close();
            }
            </span><span >return</span><span > ReadData();
        }
        </span><span >catch</span><span > (SocketException e)
        {
            Close();
        }
        </span><span >return</span> <span >null</span><span >;
    }
    </span><span >public</span> <span >string</span> SetByPipeline(<span >string</span> key, <span >string</span> value, <span >int</span><span > second)
    {
        </span><span >this</span><span >.CreatePipeline();
        </span><span >this</span><span >.EnqueueCommand(RedisCommand.SET, key, value);
        </span><span >this</span><span >.EnqueueCommand(RedisCommand.EXPIRE, key, second.ToString());
        </span><span >return</span> <span >this</span><span >.FlushPipeline();
    }     <br></span></pre>

 调用:

private void button4_Click(object sender, EventArgs e)
        {
            RedisBaseClient redis = new RedisBaseClient();
            richTextBox1.Text = redis.SetByPipeline("cnblogs", "mushroom", 1000);
        }

输出:

c# redis操作 c# 连接redis_.net_13

*2 表示2条回复。

+2 表示命令执行OK。

:1  表示命令执行的结果

总结

本文只是简单的实现,有兴趣的同学,可以继续下去。

客户端实现这块,Socket连接池管理相较复杂些。

参考资源:

http://redis.io/topics/protocol

https://github.com/ServiceStack/ServiceStack.Redis