Re: Built-in plugin for logical decoding output

On 26 September 2017 at 15:26, Alvaro Hernandez <aht(at)ongres(dot)com> wrote:

>
> That's better than nothing. But as much as interoperable json may be,
> people still need to talk the (binary) replication protocol to use it.
>

No, they don't.

They can use the SQL interface to logical decoding.

We could enhance that with a few small changes to make it a lot more useful
too. Most importantly, allow a long-polling model, where you can wait if
there's nothing to consume rather than getting an immediate empty
result-set.

I expect the walsender protocol to be dealt with by client drivers, not
user applications, much like you never really deal with the regular libpq
protocol in your app. PgJDBC and psycopg2 already support it. It'd be nice
if libpq offered some helper interfaces for C apps, and I'd help review any
such patch.

Nothing against binary output, but as you noted, we can likely use pgoutput
for that to some extent at least. I think the pressing need is json, going
by the zillion plugins out there for it.

--
Craig Ringer http://www.2ndQuadrant.com/
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