支持MySQL5.7的XA binlog事件

[agapple]

支持一下MySQL 5.7之后的XA能力：https://mysqlserverteam.com/improvements-to-xa-support-in-mysql-5-7/

`
TRANSACTION_CONTEXT_EVENT= 36,

VIEW_CHANGE_EVENT= 37,

/* Prepared XA transaction terminal event similar to Xid */
XA_PREPARE_LOG_EVENT= 38,
`

[agapple]

| mysql-bin.000011 | 13688 | Gtid | 1 | 13753 | SET @@SESSION.GTID_NEXT= 'f1ceb61a-a5d5-11e7-bdee-107c3dbcf8a7:26' |
| mysql-bin.000011 | 13753 | Query | 1 | 13846 | XA START X'74657374',X'',1 |
| mysql-bin.000011 | 13846 | Rows_query | 1 | 13897 | # update test set id = id + 5 |
| mysql-bin.000011 | 13897 | Table_map | 1 | 13985 | table_id: 256 (test.test) |
| mysql-bin.000011 | 13985 | Update_rows_v1 | 1 | 14167 | table_id: 256 flags: STMT_END_F |
| mysql-bin.000011 | 14167 | Query | 1 | 14258 | XA END X'74657374',X'',1 |
| mysql-bin.000011 | 14258 | XA_prepare | 1 | 14298 | XA PREPARE X'74657374',X'',1 |
| mysql-bin.000011 | 14298 | Gtid | 1 | 14363 | SET @@SESSION.GTID_NEXT= 'f1ceb61a-a5d5-11e7-bdee-107c3dbcf8a7:27' |
| mysql-bin.000011 | 14363 | Query | 1 | 14459 | XA ROLLBACK X'74657374',X'',1 |
| mysql-bin.000011 | 14459 | Gtid | 1 | 14524 | SET @@SESSION.GTID_NEXT= 'f1ceb61a-a5d5-11e7-bdee-107c3dbcf8a7:28' |
| mysql-bin.000011 | 14524 | Query | 1 | 14617 | XA START X'74657374',X'',1 |
| mysql-bin.000011 | 14617 | Rows_query | 1 | 14668 | # update test set id = id + 5 |
| mysql-bin.000011 | 14668 | Table_map | 1 | 14756 | table_id: 256 (test.test) |
| mysql-bin.000011 | 14756 | Update_rows_v1 | 1 | 14938 | table_id: 256 flags: STMT_END_F |
| mysql-bin.000011 | 14938 | Query | 1 | 15029 | XA END X'74657374',X'',1 |
| mysql-bin.000011 | 15029 | XA_prepare | 1 | 15069 | XA PREPARE X'74657374',X'',1 |
| mysql-bin.000011 | 15069 | Gtid | 1 | 15134 | SET @@SESSION.GTID_NEXT= 'f1ceb61a-a5d5-11e7-bdee-107c3dbcf8a7:29' |
| mysql-bin.000011 | 15134 | Query | 1 | 15228 | XA COMMIT X'74657374',X'',1

mysql xa的binlog提交格式，会在prepare时就记录到binlog并且对外可见，而后续会对xa继续进行commit或者rollback，如果执行rollback时还需要执行回滚对应的SQL(xa rollback没有记录对应的逆向binlog，需要在内存里暂缓存xa prepare的变更)

[agapple]

http://mysql.taobao.org/monthly/2017/11/06/， 一片比较不错介绍MySQL XA

[withlin]

上面地址404...

[zhmz1326]

上面地址去掉后面的逗号就能看了 http://mysql.taobao.org/monthly/2017/11/06/

[agapple]

输出格式类似：

================> binlog[mysql-bin.000012:35614] 
 BEGIN ----> Thread id: 3 ------> XA START  X'63',X'',1


 END ----> transaction id: 0 ------> XA END  X'63',X'',1
================> binlog[mysql-bin.000012:36022]


----------------> binlog[mysql-bin.000012:35459]
 ------> XA ROLLBACK  X'62',X'',1

----------------> binlog[mysql-bin.000012:36209]
 ------> XA COMMIT  X'63',X'',1

打印xa信息：

protected void printXAInfo(List<Pair> pairs) {
        if (pairs == null) {
            return;
        }

        String xaType = null;
        String xaXid = null;
        for (Pair pair : pairs) {
            String key = pair.getKey();
            if (StringUtils.endsWithIgnoreCase(key, "XA_TYPE")) {
                xaType = pair.getValue();
            } else if (StringUtils.endsWithIgnoreCase(key, "XA_XID")) {
                xaXid = pair.getValue();
            }
        }

        if (xaType != null && xaXid != null) {
            logger.info(" ------> " + xaType + " " + xaXid);
        }
    }