fix canal.GetMasterPos() for mariadb

[alarbada]

Adds support for mariadb for the method canal.GetMasterPos().

Fixes #1029

[dveeden]

Might be good to add some references to release notes and/or documentation.

This could be made into a function that takes a flavor and version and returns the query string. That would make it easier to add a unit test for this.

[alarbada]

@lance6716 thanks for accepting my pull request :)
I do need this fix to add mariadb support on the mysql conduit connector I'm working on. When do you think you could release this little fix, in a v1.12.1 or on the upcoming v1.13.0?

[dveeden]

@alarbada I assume you've tested with go mod edit -replace ... to make sure this is the only issue that's needed to make this work with recent MariaDB releases?

[dveeden]

I've created #1032

[alarbada]

@alarbada I assume you've tested with go mod edit -replace ... to make sure this is the only issue that's needed to make this work with recent MariaDB releases?

Not really, after backporting the fix to my repo I got further problems with the replication.RowsEvent. For some reason the LogPos from EventHeader is 0, I'm debugging why.

I will add an issue (hopefully a PR) once I figure out exactly why is this happening.

[dveeden]

@alarbada OK, Please let me know once you figured this out. I'll wait with releasing a new version.

[serprex]

@dveeden as a point of comparison, we're working with MariaDB on PeerDB, & had this fix in our logic already: https://github.com/PeerDB-io/peerdb/blob/84fe9ce286a8c8cc03a6369e4b7ce4b2f7505d1c/flow/connectors/mysql/mysql.go#L305

Link also shows references for versions where language shifted