Date: Wed, 14 Feb 2024 09:42:03 -0600
From: "Karl O. Pinc" <kop@karlpinc.com>
To: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Cc: "psycopg@postgresql.org" <psycopg@postgresql.org>
Subject: Re: Reporting UnicodeEncodeError info on arbitrary data sent to PG
 with psycopg3
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Hi Daniele,

On Wed, 14 Feb 2024 15:30:33 +0100
Daniele Varrazzo <daniele.varrazzo@gmail.com> wrote:

> Note however that if you just want to know the Python codec you can
> find it in `conn.info.encoding`
> (https://www.psycopg.org/psycopg3/docs/api/objects.html#psycopg.Connectio=
nInfo.encoding):
>=20
>     >>> conn.info.encoding =20
>     'iso8859-1'
>     >>> "=E2=82=AC".encode(conn.info.encoding) =20
>     ...
>     UnicodeEncodeError: 'latin-1' codec can't encode character
> '\u20ac' in position 0: ordinal not in range(256)

Thanks very much for the help.  Working directly with the encoding
of the server side, translated to python, is indeed a more
direct approach.

I did not use conn.info.encoding because the docs say that it
contains the _client_ encoding, not the server-side encoding
used to store the db content.

=46rom the link above:

```
encoding

The Python codec name of the connection=E2=80=99s client encoding.

The value returned is always normalized to the Python codec name:

conn.execute("SET client_encoding TO LATIN9")
conn.info.encoding
'iso8859-15'
```

Confirming the encodings, connecting to the  "latin1" db with psql shows:

```
$ psql -U kop latin1
psql (15.5 (Debian 15.5-0+deb12u1))
Type "help" for help.

kop_latin1=3D> show client_encoding;
 client_encoding=20
-----------------
 UTF8
(1 row)

kop_latin1=3D> show server_encoding;
 server_encoding=20
-----------------
 LATIN1
(1 row)
```

But, conn.info.encoding does return iso8859-1.

So I think your documentation has confused client
and server in this case.  If you can confirm this
for me I'll go ahead and use conn.info.encoding.

Thanks again.

Regards,

Karl <kop@karlpinc.com>
Free Software:  "You don't pay back, you pay forward."
                 -- Robert A. Heinlein