Date: Tue, 5 Jun 2018 16:09:28 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Thomas Munro <thomas.munro@enterprisedb.com>
Cc: Konstantin Knizhnik <k.knizhnik@postgrespro.ru>,
	Grigory Smolkin <g.smolkin@postgrespro.ru>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: libpq compression
Message-ID: <20180605070928.GA4973@paquier.xyz>
References: <aad16e41-b3f9-e89d-fa57-fb4c694bec25@postgrespro.ru>
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 <429cf55b-a8bf-c4ba-196d-5b45420145a1@postgrespro.ru>
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On Tue, Jun 05, 2018 at 06:04:21PM +1200, Thomas Munro wrote:
> On Thu, May 17, 2018 at 3:54 AM, Konstantin Knizhnik
> Speaking of configuration, are you planning to support multiple
> compression libraries at the same time?  It looks like the current
> patch implicitly requires client and server to use the same configure
> option, without any attempt to detect or negotiate.  Do I guess
> correctly that a library mismatch would produce an incomprehensible
> corrupt stream message?

I just had a quick look at this patch, lured by the smell of your latest
messages...  And it seems to me that this patch needs a heavy amount of
work as presented.  There are a couple of things which are not really
nice, like forcing the presentation of the compression option in the
startup packet to begin with.  The high-jacking around secure_read() is
not nice either as it is aimed at being a rather high-level API on top
of the method used with the backend.  On top of adding some
documentation, I think that you could get some inspiration from the
recent GSSAPI encription patch which has been submitted again for v12
cycle, which has spent a large amount of time designing its set of
options.
--
Michael

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