lsblk archinstall Python exception: pydantic validation error

[fatalhalt]

Which ISO version are you using?

2025-06-01

The installation log

[2025-06-25 20:29:22] - DEBUG - Hardware model detected: ASUS All Series; UEFI mode: True
[2025-06-25 20:29:22] - DEBUG - Processor model detected: Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz
[2025-06-25 20:29:22] - DEBUG - Memory statistics: 22870796 available out of 24469904 total installed
[2025-06-25 20:29:22] - DEBUG - Could not detect virtual system: ['/usr/bin/systemd-detect-virt'] exited with abnormal exit code [1]: none

[2025-06-25 20:29:22] - DEBUG - System is not running in a VM: ['/usr/bin/systemd-detect-virt'] exited with abnormal exit code [1]: none

[2025-06-25 20:29:22] - DEBUG - Virtualization detected: None; is VM: False
[2025-06-25 20:29:22] - DEBUG - Graphics devices detected: dict_keys(['NVIDIA Corporation GM204 [GeForce GTX 980] (rev a1)'])
[2025-06-25 20:29:22] - ERROR - Traceback (most recent call last):
  File "/usr/lib/python3.13/site-packages/archinstall/__init__.py", line 104, in run_as_a_module
    rc = main()
  File "/usr/lib/python3.13/site-packages/archinstall/__init__.py", line 82, in main
    _log_sys_info()
    ~~~~~~~~~~~~~^^
  File "/usr/lib/python3.13/site-packages/archinstall/__init__.py", line 36, in _log_sys_info
    debug(f'Disk states before installing:\n{disk_layouts()}')
                                             ~~~~~~~~~~~~^^
  File "/usr/lib/python3.13/site-packages/archinstall/lib/disk/utils.py", line 105, in disk_layouts
    lsblk_output = get_lsblk_output()
  File "/usr/lib/python3.13/site-packages/archinstall/lib/disk/utils.py", line 65, in get_lsblk_output
    return _fetch_lsblk_info()
  File "/usr/lib/python3.13/site-packages/archinstall/lib/disk/utils.py", line 44, in _fetch_lsblk_info
    return LsblkOutput.model_validate_json(output)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^
  File "/usr/lib/python3.13/site-packages/pydantic/main.py", line 746, in model_validate_json
    return cls.__pydantic_validator__.validate_json(
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        json_data, strict=strict, context=context, by_alias=by_alias, by_name=by_name
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
pydantic_core._pydantic_core.ValidationError: 4 validation errors for LsblkOutput
blockdevices.2.children.1.type
  Input should be a valid string [type=string_type, input_value=None, input_type=NoneType]
    For further information visit https://errors.pydantic.dev/2.11/v/string_type
blockdevices.3.children.1.type
  Input should be a valid string [type=string_type, input_value=None, input_type=NoneType]
    For further information visit https://errors.pydantic.dev/2.11/v/string_type
blockdevices.4.children.1.type
  Input should be a valid string [type=string_type, input_value=None, input_type=NoneType]
    For further information visit https://errors.pydantic.dev/2.11/v/string_type
blockdevices.5.children.1.type
  Input should be a valid string [type=string_type, input_value=None, input_type=NoneType]
    For further information visit https://errors.pydantic.dev/2.11/v/string_type

describe the problem

Python code responsible for parsing json output of lsblk is still subpar and not handling systems with software RAID or lots of disks/partitions

archinstall.log: https://0x0.st/8l9E.log
lsblk.json: https://0x0.st/8l96.json
lsblk txt: https://0x0.st/8l9I.txt

[svartkanin]

Thanks for all the logs and outputs I'll have a look

[svartkanin]

Interesting, we've seen this before #3473

It was investigated by @codefiles originally and looking at the lsblk code shared in #3473 (comment) the type should never be null...

I don't have an explanation for this but given that this has popped up again we might be better off with a catch-ignore.