Importing cadquery in python 3.9.7 on Windows fails

[fedorkotov]

To Reproduce

1. install latest mambaforge from here https://github.com/conda-forge/miniforge
2. activate conda mambaforge\Scripts\activate.bat
3. create conda environment for cadquery mamba create -n cadquery -c cadquery cq-editor=master cadquery=master
4. activate said environment mamba activate cadquey
5. run python and execute import cadquery

Backtrace

Python 3.9.7 (default, Sep 16 2021, 16:59:28) [MSC v.1916 64 bit (AMD64)] :: Anaconda, Inc. on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import cadquery
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Users\KotovF\mambaforge\envs\cadquery\lib\site-packages\cadquery\__init__.py", line 2, in <module>
    from .occ_impl.geom import Plane, BoundBox, Vector, Matrix, Location
  File "C:\Users\KotovF\mambaforge\envs\cadquery\lib\site-packages\cadquery\occ_impl\geom.py", line 5, in <module>
    from OCP.gp import (ImportError: DLL load failed while importing OCP: Не найден указанный модуль.

(*) Не найден указанный модуль = The specified module could not be found

Environment

OS: Windows 8.1

Was CadQuery installed using Conda?: yes, more precisely I used mambaforge
Output of conda list from your active Conda environment: condalist.txt
Using: Python interpreter

Additional information

Examining procmon.exe (One of SysInternals tools) logs I noticed that the last thing that happens when I run import OCP is python unsuccessfully looking for some libwebpmux.dll

See also #692

[Jojain]

Can you look in your env folder if python.exe is here ? I have had recent problem where my python interpreter would be removed from my env which then lead to such import error. (There is still a pythonw.exe is the env but no python.exe)

It seems weird but that would give me similar import errors so that may be it.

[fedorkotov]

C:\Users\KotovF\mambaforge\envs\cadquery folder which contains my environment is the first folder in PATH.
It contains both python.exe and pythonw.exe. I checked in task manager if python.exe that runs when I execute python from cmd when the env is activated is the correct one and it is.

[Jojain]

That's not a super solution but maybe try to force python 3.8 or 3.10 ( I think the later has been supported juste recently)

[fedorkotov]

python 3.10 is not supported by CQ-editor

mamba create -n cadquery_py310 -c cadquery cq-editor=master cadquery=master python=3.10

[...]
Encountered problems while solving:
  - package cq-editor-master-py3.7 requires python_abi 3.7.* *_cp37m, but none of the providers can be installed

Python 3.8 environment was created successfully with command

mamba create -n cadquery_py38 -c cadquery cq-editor=master cadquery=master python=3.8

Importing cadquery failed with same error

Python 3.8.12 (default, Oct 12 2021, 03:01:40) [MSC v.1916 64 bit (AMD64)] :: Anaconda, Inc. on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import cadquery
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Users\KotovF\mambaforge\envs\cadquery_py38\lib\site-packages\cadquery\__init__.py", line 2, in <module>
    from .occ_impl.geom import Plane, BoundBox, Vector, Matrix, Location
  File "C:\Users\KotovF\mambaforge\envs\cadquery_py38\lib\site-packages\cadquery\occ_impl\geom.py", line 5, in <module>
    from OCP.gp import (
ImportError: DLL load failed while importing OCP: Не найден указанный модуль.

I suspect this is caused by some obscure problem with one of dependencies as in #692
By the way I tried the recipe with downgraded freeimage from there and it does not work this time.

[fedorkotov]

Yesterday I tried miniforge instead of mambaforge and got the same error on import.
Today I removed miniforge and installed miniconda again on the same machine. And it worked (cadquery imported successfully, CQ-editor also works).
For reference this is the command I used for miniconda

conda create -n cadquery -c conda-forge -c cadquery cq-editor=master cadquery=master

output of conda list list-miniconda.txt
miniconda automatically selected a different python version (3.9.10 instead of 3.9.7 selected by mambaforge yesterday)

Python 3.9.10 | packaged by conda-forge | (main, Feb  1 2022, 21:22:07) [MSC v.1929 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.

I conclude that

• either something has changed in cadquery or one of its dependencies between my previous attempts with miniforge and now
• or miniforge and mambaforge are broken (at least on Windows).
• or different python version somehow influenced this
• or I'm using mambaforge and miniforge wrong

[fedorkotov]

I reinstalled mambaforge again and recreated the environment with the command from my first post. Got the same error on import again.

Then I added -c conda-forge and it worked

mamba create -n cadquery -c conda-forge -c cadquery cq-editor=master cadquery=master

I was under the impression that conda-forge is used by default in mambaforge and miniforge
To cite README from their repository

• conda-forge set as the default (and only) channel.
  • Packages in the base environment are obtained from the conda-forge channel.

Turned out to be not true

[adam-urbanczyk]

Could you try running ntldd on the OCP binary and share the result? You might need to install ntldd (conda install -c conda-forge m2w64-ntldd-git).

ntldd -R OCP....
ntldd --list_import OCP...

[fedorkotov]

Here is what I did. Let me know if this is not what you meant. I've never used ntldd before

1. I recreated a broken environment

mamba create -n cadquery_noforge -c cadquery cq-editor=master cadquery=master

2. activated this environment with mamba activate cadquery_noforge
3. verified that it is broken

Python 3.9.7 (default, Sep 16 2021, 16:59:28) [MSC v.1916 64 bit (AMD64)] :: Ana
conda, Inc. on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import OCP
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: DLL load failed while importing OCP: Не найден указанный модуль.

4. installed ntldd with mamba install -c conda-forge m2w64-ntldd-git
5. tried executing ntldd -R OCP. It said OCP: not found
6. found the only thing that had a signature of windows executable and OCP in it's name inside environment folder - OCP.cp39-win_amd64.pyd
7. the following command

ntldd -R mambaforge\envs\cadquery_noforge\Lib\site-packages\OCP.cp39-win_amd64.pyd > ntldd-R.OCP.cp39-win_amd64.pyd.txt

produced the this file ntldd-R.OCP.cp39-win_amd64.pyd.txt
8. the following command

ntldd --list-imports mambaforge\envs\cadquery_noforge\Lib\site-packages\OCP.cp39-win_amd64.pyd > ntldd-list-imports.OCP.cp39-win_amd64.pyd.txt

produced this file ntldd-list-imports.OCP.cp39-win_amd64.pyd.txt

[adam-urbanczyk]

I cannot reproduce this issue. libwebpmux comes from libwebp-base and with 1.2.2-h8ffe710_1 (resolved by conda on a fresh install) all works fine for me.

[fedorkotov]

I tried it on my Linux box (Ubuntu 20.04) today. Can not reproduce it there. mambaforge installs everything correctly even if I omit -c conda-forge argument in environment creation command.

On Windows machine I cleared conda's cache as described in wiki to make use of your last commit #992. And still it reproduces reliably every time

mamba create -n cadquery -c cadquery cq-editor=master cadquery=master

produces a broken environment where OCP can't be imported. And

mamba create -n cadquery -c conda-forge -c cadquery cq-editor=master cadquery=master 

installs everything properly. OCP and cadquery can be imported without issues.

Perhaps something is not right in windows version of mambaforge. Maybe it reproduces only on Windows 8.1 but not on newer versions.
I've found a workaround (just add -c conda-forge when using miniforge on Windows) so this can be closed if you don't have further remarks and don't need additional information from me to investigate further.