On Tue, May 03, 2022 at 02:41:47PM +0000, John Rouillard wrote:
> 
> From what I can find, psycopg2 version 2.8 released on Apr 4, 2019
> introduced the errors module. So that's three years ago.
> redhat/debian/ubuntu etc. have a 5 year (free/full support) cycle on
> their (lts) releases. While it would be nice to support back to 2017
> versions of psycopg2, the question is how much of a mess will it be
> for how much gain.
[...]
> My take on this is to not change any code. Instead add a minimum
> required version of psycopg2 to the notes.

Yes.
I've investigated the errors we use from the psycopg2.errors module. It
is almost impossible to find out with what to replace these errors in
the older version. Debian oldstable has 2.7.7 while stable has 2.8.6.
And the code would be awkward. With try/except in import or similar.

Note that we use the errors module only in the tests and in the postgres
indexer in indexer_postgresql_fts.py. Not in the database code itself.
The backend code works just fine with 2.7.7. (when not using the
postgres indexer). I do have several production versions running that
use the latest roundup version.

> We have a good workaround. Install psycopg2 version 2.8 or newer in a
> virtual env via pip. This preserves the system version.

Yes, I think documenting the version + the possible workaround should be
fine. I'll try to come up with and addition to the docs.

Ralf
-- 
Dr. Ralf Schlatterbeck                  Tel:   +43/2243/26465-16
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