Re: parallel workers and client encoding

On Mon, Jun 13, 2016 at 10:27 PM, Peter Eisentraut
<peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:
> Modulo that last point, here is a patch that shows how I think this could
> work, in combination with the patch I posted previously that sets the
> "client encoding" in the parallel worker to the server encoding.
>
> This patch disassembles the NotificationResponse message with a temporary
> client encoding, and then sends it off to the real frontend using the real
> client encoding.
>
> Doing it this way also takes care of a few special cases that
> NotifyMyFrontEnd() handles, such as a client with protocol version 2 that
> doesn't expect a payload in the message.

How does this address the concern raised in the last sentence of
https://www.postgresql.org/message-id/CA+TgmoaAAEXmjVMB4nM=znF_5b9JhUim6q3aFrO4SpT23TiN8g@mail.gmail.com
? It seems that if an error occurs between the two SetClientEncoding
calls, the change will persist for the rest of the session, resulting
in chaos.

--
Robert Haas
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