Flet build error with opencv cv2.

[hi-one-gg]

1. I made an app using flet create myapp.
2. Added opencv-python to requirements.txt in myapp directory.
3. I made a desktop app using flet build windows ./myapp.
4. When I run the created app, I get an error as shown in the picture below.

ENV.

Windows10 flet 0.21 and 0.22

[lekshmanmj]

please try just by giving opencv instead of opencv-python in requirements.txt, and let me know if it helps you solve the issue.

[ivangermes]

IMHO This is because packaging removes the "py" files, leaving only the "pyc" files.

As a quick fix, you can add config.py and config3.py to data/flutter_assets/app/app.zip/__pypackages__/cv2/ manually. ( you can take these files from site-packages/cv2/ ).

Update: You need to add config.py and config3.py to resulted app.zip. This app.zip is created after the build in build/YOUR_PLATFORM/data/flutter_assets/app/. The path in app.zip to put the files is /__pypackages__/cv2/.

[AltugEngin]

please try just by giving opencv instead of opencv-python in requirements.txt, and let me know if it helps you solve the issue.

exactly same issue for me too... Unfortunately it didn't work for me

[AltugEngin]

Traceback (most recent call last): File "", line 40, in File "", line 229, in run_module File "", line 88, in _run_code File "/tmp/serious_python_tempBWLPXY/main.py", line 2, in File "/tmp/serious_python_tempBWLPXY/pypackages/cv2/init.py", line 181, in File "/tmp/serious_python_tempBWLPXY/pypackages/cv2/init.py", line 111, in bootstrap File "/tmp/serious_python_tempBWLPXY/pypackages/cv2/init.py", line 109, in load_first_config ImportError: OpenCV loader: missing configuration file: ['config.py']. Check OpenCV installation.

[AltugEngin]

IMHO This is because packaging removes the "py" files, leaving only the "pyc" files.

As a quick fix, you can add config.py and config3.py to data/flutter_assets/app/app.zip/__pypackages__/cv2/ manually. ( you can take these files from site-packages/cv2/ ).

it didn't work neither

[hi-one-gg]

IMHO This is because packaging removes the "py" files, leaving only the "pyc" files.

As a quick fix, you can add config.py and config3.py to data/flutter_assets/app/app.zip/__pypackages__/cv2/ manually. ( you can take these files from site-packages/cv2/ ).

@ivangermes It didnt work...

[hi-one-gg]

please try just by giving opencv instead of opencv-python in requirements.txt, and let me know if it helps you solve the issue.

@lekshmanmj Yes I tried but it didn't work.

[avagst3]

Hi, I just had the same error. I use flet 0.22 and opencv 4.9.0.80. manually add the file into the source folder don't work, I also tried to add the folder with .py transform in .pyi but it still doesn't work. Anything new about this problem?

[ivangermes]

@AltugEngin

it didn't work neither

@blackCmd

It didnt work...

@avagst3

You need to add config.py and config3.py to resulted app.zip. This app.zip is created after the build in build/YOUR_PLATFORM/data/flutter_assets/app/. The path in app.zip to put the files is /__pypackages__/cv2/.

[EmmanuelMMontesinos]

@ivangermes Thank you very much! I had the same error and it was driving me crazy (I'm a newbie). Then I got this error:

RuntimeError: cannot cache function '_make_tree': no locator available for file 'C:\\Users\\My_user\\AppData\\Local\\Temp\\serious_python_temp32194b5c\\__pypackages__\\pymatting\\util\\kdtree.py'

But applying your solution with those dependencies (copy them where they belong in app.zip everything goes perfect.) 💯

Edit: As the process can be tedious and confusing, I created this tool (with flet XD) It's ugly as hell but it works! The only doubt I have is if it could be a bad practice to include the dependencies like this...

I look forward to hearing your answers Flet Package Loader

[avagst3]

@ivangermes I add the file as you say but .exe still use the same Temp folder (so my change is not applyed). Any solution ?

[EmmanuelMMontesinos]

@avagst3 apply it to the generated Flet build It is in your_project_flet: \build\windows\data\flutter_assets\app\app.zip But if you have several dependencies that need this solution I recommend the tool I have created with the solution of @ivangermes Flet Package Loader

[ivangermes]

@EmmanuelMMontesinos I use a similar automation. I made a simple bash/python script to add a file to zip. And use it in my CI/CD system.

function add_file_2_zip {
python3 -c "
import zipfile as zf, sys
with zf.ZipFile(sys.argv[1], 'a') as z:
    z.write(sys.argv[2], sys.argv[3])
" $1 $2 $3
}

zip_file="/home/user/proj/OpenStitching/build/linux/data/flutter_assets/app/app.zip"
src="/home/user/proj/OpenStitching/venv/lib/python3.11/site-packages/cv2/config.py"
dst="/__pypackages__/cv2/config.py"

add_file_2_zip $zip_file $src $dst