gdal_array_fix.md

ModuleNotFoundError: No module named '_gdal_array'

Setting up a correct environment with GDAL is not an easy task, and when you build the Docker Image to run the program under Unbuntu, it is possible to encounter ModuleNotFoundError: No module named '_gdal_array' after runnning python deploy.py. There are many fixes online, but I found the following to be the only way that worked.

1. Test If You Have The Issue

After adding the program under a docker container built from the Docker Image (you should see something like root@7702bddeadad: in terminal), run:

python 
>>> from osgeo import gdal
>>> from osgeo import gdal_array
>>> exit()

If you don't see anything returned, you can skip the rest of the instruction. No fix needed. Otherwise, go to Section 2.

2. Uninstall numpy and GDAL

To uninstall numpy and GDAL, run:

pip uninstall numpy 
pip uninstall GDAL

3. Delete .cache

This is important! Many who tried this method but failed to make it work were because they skipped this step. If .cache is not deleted, pip will re-use the cached version of the wheel, which will cause the problem. To delete .cache, run:

cd /
find ~/.cache -delete

4. Re-install numpy and GDAL

You must reinstall numpy before GDAL for this to work. Follow:

pip install numpy
pip install GDAL==3.4.1

Now repeat Section 1 to confirm the fix.