Python 3.11 compatibility

[dvarrazzo]

At the moment, psycopg-c build is not compatible with Python 3.11. We probably need to wait for release of Cython 3.0.0a11 because the errors during build seem already addressed and merged to master:

• Adapt to exc_info changes in Py3.11 cython/cython#4500
• [BUG] Use of ob_shash is deprecated on 3.11 cython/cython#4721

[septatrix]

It would also be nice to replace the str in the Query type alias with LiteralString (sadly there is no bytes equivalent)

[itsankitkp]

On related note:
Build is failing for psycopg_c (working fine for psycopg[dev,test])
Tested on Python 3.12.0a0 (built from source)
Run
pip install -e ./psycopg_c
Response:
res.txt

[dvarrazzo]

@itsankitkp they seem cython-related issues. Did you build it with the master version of cython? 3.0.0a10 surely doesn't support Python 3.12.

[itsankitkp]

Yes, I build with master version of CPython (Python 3.12.0a0 (heads/main:16b6e14) [GCC 11.2.0] on linux).

Might need to dig deeper.

[dvarrazzo]

Yes, I build with master version of CPython

And which version of Cython?

[itsankitkp]

Pip freeze result as follows:
Cython==0.29.30

[dvarrazzo]

Cython 0.x definitely doesn't work. As already stated, to have a chance to compile for Python 3.11 you need cython from master, for the reasons explained in this ticket. I expect Python 3.12 to need at least the same.

[itsankitkp]

I did try that but it is still failing with Cython==3.0.0a10 (Cython master)

Might need to wait for 3.0.0a11

[itsankitkp]

Error log error.txt

[honglei]

https://pythoninsider.blogspot.com/2022/08/python-3110rc1-is-now-available.html
Any updates for Python3.11rc1？
The https://pypi.org/project/psycopg/#files version 3.1.1 still not work under Python3.11.

C:\Users\Admin>c:/python311/python.exe -m pip install -U psycopy 
ERROR: Could not find a version that satisfies the requirement psycopy (from versions: none)
ERROR: No matching distribution found for psycopy

[dvarrazzo]

You have a typo in the package name. You can probably install psycopg and it should probably work already. You must have your libpq.dll in the system: see the install docs for more details.

psycopg[binary] needs a specific release, which won't happen until the official Python 11 release: it is advised against loading packages on pypi for unstable releases.

I have noticed that Cython 3.0.0a11 has been released: will try if it fixes all the problems and merge this branch so that we can release packages for Py11 as soon as it's final.

[dvarrazzo]

The py311 branch passes all the test and builds packages successfully for Python 3.11.

To be merged to master and released as soon as Python 3.11 is officially released.

[septatrix]

PyPi supports pre-releases. What do you think about publishing the preliminary version as such a pre-release to allow early adopters to already test their application with it?