[regression] GrubConfig' object is not subscriptable when grub.install-devices is used

[Dariusz Gadomski]

Commit 4587fd40dfd7eabd6677004e91340edcfe5a7472 has made some refactoring around how GrubConfig properties may be accessed. There was a log message where old syntax has been left: curtin/commands/curthooks.py:782

This leads to causing a Python TypeError:
TypeError: 'GrubConfig' object is not subscriptable
'GrubConfig' object is not subscriptable

The fix seems to be just converting this message not to use the [] syntax.

This seems pretty important as most likely it affects all installations making use of grub.install-devices parameter.

[Dariusz Gadomski (dgadomski)]

Merge proposal with the fix: https://code.launchpad.net/~dgadomski/curtin/+git/curtin/+merge/466000

[Dagmawi Biru (dagbiru)]

If anyone encounters this issue, I've found success in an temporary workaround, invoking grub manually instead of via curtin like so:

late-commands:
- 'curtin in-target -- /usr/sbin/grub-install /dev/vda'

[Dariusz Gadomski (dgadomski)]

The user who run into this was using a subiquity autoinstall setup with the following content in their config:

storage:
  grub:
    reorder_uefi: false
    install_devices:
    - /dev/sda

I believe any usage of the install_devices option in an automated subiquity installation will trigger this issue.