"Step 1: Install Video2X and Dependencies" fails on pdm.pep517.exceptions.PEP621ValidationError: {'license-expression': ['unknown field']}

[Almeros]

When running Step 1 in the Colab I get the following error. As far as I know I followed step 0 correctly. I tried it several times yesterday and today. Restarting the runtime many times. I'm not familiar with Colab so perhaps the problem just lies with me not understanding what to do?

...
WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
Installing build dependencies ... done
Running command Getting requirements to build wheel
Traceback (most recent call last):
File "/usr/local/lib/python3.7/dist-packages/pip/_vendor/pep517/in_process/_in_process.py", line 351, in
main()
File "/usr/local/lib/python3.7/dist-packages/pip/_vendor/pep517/in_process/_in_process.py", line 333, in main
json_out['return_val'] = hook(**hook_input['kwargs'])
File "/usr/local/lib/python3.7/dist-packages/pip/_vendor/pep517/in_process/_in_process.py", line 118, in get_requires_for_build_wheel
return hook(config_settings)
File "/tmp/pip-build-env-5y2y85sv/overlay/lib/python3.7/site-packages/pdm/pep517/api.py", line 26, in get_requires_for_build_wheel
if builder.meta.config.run_setuptools:
File "/tmp/pip-build-env-5y2y85sv/overlay/lib/python3.7/site-packages/pdm/pep517/base.py", line 154, in meta
self._meta.validate(True)
File "/tmp/pip-build-env-5y2y85sv/overlay/lib/python3.7/site-packages/pdm/pep517/metadata.py", line 58, in validate
return validate_pep621(self.data, raising)
File "/tmp/pip-build-env-5y2y85sv/overlay/lib/python3.7/site-packages/pdm/pep517/validator.py", line 85, in validate_pep621
raise PEP621ValidationError(validator.errors)
pdm.pep517.exceptions.PEP621ValidationError: {'license-expression': ['unknown field']}
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.
full command: /usr/bin/python3.7 /usr/local/lib/python3.7/dist-packages/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /tmp/tmpnrv61vuo
cwd: /tmp/pip-install-kzlt0tky/video2x_c67fbdfff34a4f63a53bc6fa4a542a55
Getting requirements to build wheel ... error
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.

---

Edit: this happens in 5.0.0 beta-6 but works in 5.0.0 beta-4, so if you also encounter this problem, you can change it in colab in the script of Step 1.

For me this works, but the bug/problem is still there in beta-6 so I'm not sure that this issue should be closed.

[jedidiahgamaliel]

Ran into the same problem.

[rogerb831]

I'm also getting this error.

[stavlocker]

Can confirm this doesn't happen in 5.0.0 beta-4, so you could try changing that in the installation script (even though I am currently encountering different issues after doing this).

[quito96]

Same problem here

[ColtonWehking]

Can confirm this doesn't happen in 5.0.0 beta-4, so you could try changing that in the installation script (even though I am currently encountering different issues after doing this).

I can confirm beta-4 is working fine. As far as other issues, I encountered many too. Eventually I upgraded to a paid google colab, $10, and everything got fixed. Might be some resource issue?

[Medformatik]

I am facing the same problem.

[quito96]

I am facing the same problem.

switch to 5.0.0 beta-4 this works ;)

[xmusjackson]

It's an issue with the pyproject.toml. Based on this commit to pdm-pep517 (the backend used for this project):
pdm-project/pdm-backend@aa7aecb,
'license-expression' is once again 'license'. It's easy to work around. Just change the 'license-expression' field to 'license' in pyproject.toml and all will work.

diff --git a/pyproject.toml b/pyproject.toml
index 6edaf1c..c54c2e9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -3,7 +3,7 @@ name = "video2x"
description = "A video/image upscaling and frame interpolation framework"
readme = "README.md"
requires-python = ">=3.7"
-license-expression = "AGPL-3.0-or-later"
+license = "AGPL-3.0-or-later"
keywords = [
"super-resolution",
"upscaling",

I submitted a pull request with this patch.