Re: The ultimate extension hook.

On Thu, 24 Sep 2020 17:08:44 +1200
David Rowley <dgrowleyml@gmail.com> wrote:
[...]
> I wondered if there was much in the way of use-cases like a traffic
> filter, or statement replication. I wasn't sure if it was a solution
> looking for a problem or not, but it seems like it could be productive
> to talk about possibilities here and make a judgement call based on if
> any alternatives exist today that will allow that problem to be solved
> sufficiently in another way.

If I understand correctly the proposal, this might enable traffic capture using
a loadable extension.

This kind of usage would allows to replay and validate any kind of traffic from
a major version to another one. Eg. to look for regressions from the application
point of view, before a major upgrade.

I did such regression tests in past. We were capturing production traffic
using libpcap and replay it using pgshark on upgraded test env. Very handy.
However:

* libpcap can drop network packet during high load. This make the capture
  painful to recover past the hole.
* useless with encrypted traffic

So, +1 for such hooks.

Regards,