利用Python my-replication读取mysql的binlog

一、准备

1. Python 2.7；
2. Python 3.4 or Python 3.5 or Python 3.6；
3. MySQL 5.5 or MySQL 5.6 or MySQL 5.7；

二、Mysql 配置

1. Mysql 开启 binlog

查看 Mysql 是否开启 binlog show variables like 'log_bin' 如果 Value 为 OFF 则为未启日志文件。
找到 my,cnf 中 [mysqld] 添加如下

[mysqld]
# binlog 配置
server-id = 1
# 目录需要有写的权限
log-bin = /var/lib/mysql-binlog/mysql-bin.log
expire-logs-days = 10
max-binlog-size = 100M
binlog-format = row

重启mysql后 show variables like 'log_bin' ， Value 为 ON即可
查询binlog 变动信息 show binlog events;

Binlog要满足如下条件：

MySQL> show variables like 'log_bin';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| log_bin       | ON    |
+---------------+-------+
1 row in set (0.01 sec)

MySQL>show variables like 'binlog_format';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| binlog_format | ROW   |
+---------------+-------+
1 row in set (0.00 sec)

MySQL>show variables like 'binlog_row_image';
+------------------+-------+
| Variable_name    | Value |
+------------------+-------+
| binlog_row_image | FULL  |
+------------------+-------+
1 row in set (0.00 sec)

MySQL> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      431 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+

2. 配置同步账号

自己伪装成一个 slave 不断的从 MySQL 数据库获取 binlog 并解析。

GRANT SELECT, REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'replicator'@'%' IDENTIFIED BY '123456';
# 刷新权限
flush privileges;

三、Python

安装 mysql-replication 包

pip install mysql-replication

代码例子：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
from pymysqlreplication import BinLogStreamReader
from pymysqlreplication.row_event import (
    DeleteRowsEvent,
    UpdateRowsEvent,
    WriteRowsEvent,
)
import sys
import json

def main():
    mysql_settings = {
    	'host': '127.0.0.7',
        'port': 3306, 
        'user': 'replicator', 
        'passwd': '123456'
        }
    stream = BinLogStreamReader(
        connection_settings=mysql_settings,
        server_id=101,
        blocking=True,
        only_schemas=['zow'],  # 监控表名
        only_events=[DeleteRowsEvent, WriteRowsEvent, UpdateRowsEvent],
        resume_stream=True,
        log_file='mysql-bin.000001', log_pos=0)  #show master status; 中的Position 

    for binlogevent in stream:
        for row in binlogevent.rows:
            event = {"schema": binlogevent.schema, "table": binlogevent.table, "log_pos": binlogevent.packet.log_pos}
            if isinstance(binlogevent, DeleteRowsEvent):
                event["action"] = "delete"
                event["values"] = dict(row["values"].items())
                event = dict(event.items())
            elif isinstance(binlogevent, UpdateRowsEvent):
                event["action"] = "update"
                event["before_values"] = dict(row["before_values"].items())
                event["after_values"] = dict(row["after_values"].items())
                event = dict(event.items())
            elif isinstance(binlogevent, WriteRowsEvent):
                event["action"] = "insert"
                event["values"] = dict(row["values"].items())
                event = dict(event.items())
            print( json.dumps(event))
            sys.stdout.flush()

    stream.close()


if __name__ == "__main__":
    main()

运行结果：

# python mysql-replication.py 
{"table": "test4", "log_pos": 884, "action": "insert", "schema": "test", "values": {"id": 1, "data2": "World", "data": "Hello"}}
{"table": "test4", "after_values": {"id": 1, "data2": "Hello", "data": "World"}, "log_pos": 1111, "action": "update", "schema": "test", "before_values": {"id": 1, "data2": "World", "data": "Hello"}}
{"table": "test4", "log_pos": 1320, "action": "delete", "schema": "test", "values": {"id": 1, "data2": "Hello", "data": "World"}}
{"table": "test4", "log_pos": 1529, "action": "insert", "schema": "test", "values": {"id": 2, "data2": "World", "data": "Hello"}}
{"table": "test4", "log_pos": 3010, "action": "delete", "schema": "test", "values": {"id": 2, "data2": "Hello", "data": "World"}}

参考：
https://github.com/noplay/python-mysql-replication
其他语言：
Java: https://github.com/shyiko/mysql-binlog-connector-java
GO: https://github.com/siddontang/go-mysql
PHP: Based on this this project https://github.com/krowinski/php-mysql-replication and https://github.com/fengxiangyun/mysql-replication