mysql 协议的OK包及解析

git

https://github.com/sea-boat/mysql-protocol

概况

mysql客户端与mysql服务端交互过程中，当服务端完成客户端的某命令时则会返回OK包。

mysql通信报文结构

类型	名字	描述
int<3>	payload长度	按照the least significant byte first存储，3个字节的payload和1个字节的序列号组合成报文头
int<1>	序列号
string	payload	报文体，长度即为前面指定的payload长度

OK包

Payload

Type	Name	Description
int<1>	header	[00] or [fe] the OK packet header
int	affected_rows	affected rows
int	last_insert_id	last insert-id
	if capabilities & CLIENT_PROTOCOL_41 {
int<2>	status_flags	Status Flags
int<2>	warnings	number of warnings
	}elseif capabilities & CLIENT_TRANSACTIONS {
int<2>	status_flags	Status Flags
	}
	if capabilities & CLIENT_SESSION_TRACK {
string	info	human readable status information
	if status_flags & SERVER_SESSION_STATE_CHANGED
string	session_state_changes	session state info
	}
	} else {
string	info	human readable status information
	}

更多详情 ： http://dev.mysql.com/doc/internals/en/packet-OK_Packet.html

Status Flags

Flag	Value
SERVER_STATUS_IN_TRANS	0x0001
SERVER_STATUS_AUTOCOMMIT	0x0002
SERVER_MORE_RESULTS_EXISTS	0x0008
SERVER_STATUS_NO_GOOD_INDEX_USED	0x0010
SERVER_STATUS_NO_INDEX_USED	0x0020
SERVER_STATUS_CURSOR_EXISTS	0x0040
SERVER_STATUS_LAST_ROW_SENT	0x0080
SERVER_STATUS_DB_DROPPED	0x0100
SERVER_STATUS_NO_BACKSLASH_ESCAPES	0x0200
SERVER_STATUS_METADATA_CHANGED	0x0400
SERVER_QUERY_WAS_SLOW	0x0800
SERVER_PS_OUT_PARAMS	0x1000
SERVER_STATUS_IN_TRANS_READONLY	0x2000
SERVER_SESSION_STATE_CHANGED	0x4000

OK包操作

OK包类

/**
*
* @author seaboat
* @date 2016-09-25
* @version 1.0
* <pre><b>email: </b>849586227@qq.com</pre>
* <pre><b>blog: </b>http://blog.csdn.net/wangyangzhizhou</pre>
* <p>mysql ok packet.</p>
*/
public class OKPacket extends MySQLPacket {
public static final byte HEADER = 0x00;
public static final byte[] OK = new byte[] { 7, 0, 0, 1, 0, 0, 0, 2, 0, 0,
0 };

public byte header = HEADER;
public long affectedRows;
public long insertId;
public int serverStatus;
public int warningCount;
public byte[] message;

public void read(byte[] data) {
MySQLMessage mm = new MySQLMessage(data);
packetLength = mm.readUB3();
packetId = mm.read();
header = mm.read();
affectedRows = mm.readLength();
insertId = mm.readLength();
serverStatus = mm.readUB2();
warningCount = mm.readUB2();
if (mm.hasRemaining()) {
this.message = mm.readBytesWithLength();
}
}

public void write(ByteBuffer buffer) {
BufferUtil.writeUB3(buffer, calcPacketSize());
buffer.put(packetId);
buffer.put(header);
BufferUtil.writeLength(buffer, affectedRows);
BufferUtil.writeLength(buffer, insertId);
BufferUtil.writeUB2(buffer, serverStatus);
BufferUtil.writeUB2(buffer, warningCount);
if (message != null) {
BufferUtil.writeWithLength(buffer, message);
}
}

@Override
public int calcPacketSize() {
int i = 1;
i += BufferUtil.getLength(affectedRows);
i += BufferUtil.getLength(insertId);
i += 4;
if (message != null) {
i += BufferUtil.getLength(message);
}
return i;
}

@Override
protected String getPacketInfo() {
return "MySQL OK Packet";
}

}

测试类

/**
*
* @author seaboat
* @date 2016-09-25
* @version 1.0
* <pre><b>email: </b>849586227@qq.com</pre>
* <pre><b>blog: </b>http://blog.csdn.net/wangyangzhizhou</pre>
* <p>test ok packet.</p>
*/
public class OKPacketTest {
@Test
public void produce() {
OKPacket ok = new OKPacket();
ok.packetId = 2;
ok.affectedRows = 0;
ok.insertId = 0;
ok.serverStatus = 2;
ok.warningCount = 0;
ByteBuffer buffer = ByteBuffer.allocate(256);
ok.write(buffer);
buffer.flip();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes, 0, bytes.length);
String result = HexUtil.Bytes2HexString(bytes);
System.out.println(result);
assertTrue(Integer.valueOf(result.substring(0, 2), 16) == result
.length() / 2 - 4);

OKPacket ok2 = new OKPacket();
ok2.read(bytes);
//auth ok
assertTrue(result.equals("0700000200000002000000"));
}

}

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