Support new postgres features

[nikita-safonov]

Hello!

Currently pq is stopped in development and does not support any new postgres features like new environment variables, parameters and so on.

Right now I'm trying to deploy an exporter in kubernetes and want to collect metrics from master, but I have 3 PG instances and patroni, so I don't know who is master and who is slave, so I tried to use target_session_attrs parameter. But pq doesn't support it because MR hasn't been merged for 5 years...

If I knew GO, I would create MR to migrate to pgx, which is currently under active development and supports all new features.

Thanks.

[vvitad]

I have completely the same problem

[vvitad]

That feature is needed! I don't want to collect metrics I won't use from replica. It would be garbage.

[dewey]

Pull requests are welcome! (See "help wanted" label)