Support LOCAL INFILE request

[masahide]

Make LOAD DATA LOCAL INFILE available.

[lance6716]

Even if we turn on the capability flag, in fact we don't support LOAD DATA INFILE?

https://dev.mysql.com/doc/dev/mysql-server/latest/page_protocol_com_query_response_local_infile_request.html

It wil return a 0xFB packet and searching for LocalInFile_HEADER you can see we simply return ErrMalformPacket

[masahide]

I apologize for the confusion, you're absolutely right. I used go-mysql/client to create a MySQL proxy.
When using the LOCAL INFILE in this proxy, it is necessary to configure the CLIENT_LOCAL_FILES capability when connecting from go-mysql/client to the MySQL server, and this modification was required for that. This proxy operates by using go-mysql/client only for MySQL handshake, and after connection, the client's net.Conn is directly transferred to the server-side net.Conn, hence making the LOCAL INFILE operational with just the LocalInFile_HEADER.
https://github.com/masahide/mysql8-audit-proxy/blob/main/pkg/mysqlproxy/clntsess.go#L33-L38

Project top page: https://github.com/masahide/mysql8-audit-proxy

[lance6716]

lgtm. Can you help fix the linter? If you don't have enough time, I'll make a commit tomorrow

[lance6716]

btw, what's your golang version? in #799 we are considering to drop support for older golang versions

[masahide]

I am using go version 1.20.