“ModuleNotFoundError: No module named ‘distutils.util’” when trying to build snaps on Launchpad (but works locally)

[Pierre Equoy]

This initially started as a discussion on the forum, so the whole gist of the problem is explained there:

https://forum.snapcraft.io/t/modulenotfounderror-no-module-named-distutils-util-when-trying-to-build-snaps-on-launchpad-but-works-locally/15434

In a nutshell:

- A snapcraft recipe can be build locally on my laptop, but fails to build on Launchpad build infrastructure due to "No module named 'distutils.util'" error.
- The problem seems to be that there are some parts built before the part where it fails, pulling some python3 dependencies (but not python3-distutils) that are cached in the stage directory
- When the main part is built, snapcraft tries to used cached data instead of pulling fresh one, resulting in a missing dependency

Workaround

In my case, cjp256 suggested to add `python3-distutils` to sosreport part `stage-packages`.

[Pierre Equoy (pieq)]

I can confirm the workaround provided by cjp256 works as expected for all 3 architectures I build my software against. Thank you Chris!

→ https://launchpadlibrarian.net/466606658/buildlog_snap_ubuntu_bionic_amd64_qabro_BUILDING.txt.gz
→ https://launchpadlibrarian.net/466608162/buildlog_snap_ubuntu_bionic_armhf_qabro_BUILDING.txt.gz
→ https://launchpadlibrarian.net/466608336/buildlog_snap_ubuntu_bionic_arm64_qabro_BUILDING.txt.gz

[Dmitrii Shcherbakov (dmitriis)]

Also encountered this while building using multipass.

[Dmitrii Shcherbakov (dmitriis)]

Also note that you might encounter just this message on subsequent runs which hides the real issue:

Failed to run '/root/stage/usr/bin/python3 -m pip': Exited with code 1.

See https://bugs.launchpad.net/snapcraft/+bug/1882124

[Joseph Borg (joeborg)]

We had the same issue in MicroK8s. Chris kindly provided this workaround https://github.com/ubuntu/microk8s/commit/73d181f2bce1d9834c42a7ecc43e11e0062c61e8