Problems with PyQt5 on Raspi 5 / Debian Bookworm

[ullix]

Thanks. I filed a bug report at Raspian:

https://bugs.launchpad.net/raspbian/+bug/2046806

ullix



Am 18.12.23 um 11:19 schrieb Phil Thompson:
> On 18/12/2023 07:40, ullix wrote:
>> Am 15.12.23 um 17:34 schrieb Phil Thompson:
>>> On 15/12/2023 16:23, ullix wrote:
>>>> I got the new Raspi 5 and tested a few things. I used pip to
>>>> install/modify a dozen packages, and all worked except for *PyQt5.*
>>>>
>>>> PyQt5 had been apt-installed as version 5.15.9, and worked in tests of
>>>> mine. But what failed was when trying to upgrade to 5.15.10. After
>>>> closer instepction I apt-removed the apt-installed PyQt5, and tried to
>>>> pip-install that very same version. It failed with :
>>>>
>>>>   Preparing metadata (pyproject.toml): started
>>>>   Preparing metadata (pyproject.toml): finished with status 'error'
>>>>
>>>> Full error report in attached file.
>>>>
>>>> After reinstalling 'python3-pyqt5' via apt, it worked again.
>>>>
>>>> Where is the problem: Raspi, Debian, pip, pyqt5?
>>>>
>>>> ullix
>>>>
>>>>
>>>> On Raspi 5 I used the default OS install:
>>>>
>>>>
>>>>      Raspberry Pi OS with desktop
>>>>
>>>>  * Release date: December 5th 2023
>>>>  * System: 64-bit
>>>>  * Kernel version: 6.1
>>>>  * Debian version: 12 (bookworm)
>>>
>>> pip is attempting to build from source and needs extra options to be 
>>> specified. You also need a reasonably up to date pip. It's much 
>>> easier to use pip to install sip and PyQt-builder and download the 
>>> sdist, then run sip-install in the untarred sdist.
>>>
>>> Phil
>>
>>
>> Thanks, but I don't understand what the consequences of your statement
>> are. I also believe the problem indicates a broader problem.
>>
>> Debian 12 (bookworm), the basis for the current Raspberry Pi OS, is
>> drawing its conclusions from the success of Python and are now
>> blocking the possibility of changing the Python installation of the OS
>> by pip. (I know you can break this by deleting file file
>> 'EXTERNALLY-MANAGED' of pip-install with flag '--break-system-files',
>> but this is defeating the purpose of this blocking).
>>
>> They now direct everyone towards a venv install. This works, though it
>> requires extra steps.
>
> I can see the justification of that for a desktop system which may be 
> running a number of Python applications with conflicting dependencies. 
> I'm less convinced that it is appropriate for an embedded platform 
> more likely to be running a single application.
>
>> However, for a clean venv you now need to install e.g. PyQt5, and this
>> fails, as outlined above. Is this a bug? Is this a flaw introduced by
>> the Raspi packagers? Or is this a introduced by Debian packagers,
>> which means it will soon become a broader problem?
>
> It's not a bug, it's a consequence of those policy decisions.
>
>> Can you say what packages need to be installed to make installation of
>> PyQt5 possible? Or is this a much deeper problem?
>
> The build instructions are here...
>
> https://www.riverbankcomputing.com/static/Docs/PyQt5/installation.html#building-and-installing-from-source 
>
>
> ...but you also need platform-specific development packages installed.
>
> This is not a PyQt-specific problem - it will affect any Python 
> package that contains C/C++ extension modules and does not currently 
> have Raspi wheels available on PyPI.
>
> What's needed is somebody to step up and create Raspi PyQt wheels (I 
> don't have the resources) which can be uploaded to PyPI so that "pip 
> install PyQt5" will just work. I've made attempts over the years to 
> engage with the Raspi community to address this but have never had a 
> response.
>
> Phil