[Bug] (alpha) 500 internal server error (pydantic ValidationError)

[sargunv]

RomM version
1.5.0 alpha 1

Describe the bug
When I load the Dreamcast platform (in which I have some multi disc games), I get "Couldn't fetch roms for platform ID 15: AxiosError: Request failed with status code 500" in the UI. The 500 is on /api/roms?platform_id=15&search_term=&order_by=name&order_dir=asc. Checking the log, I see a pydantic ValidationErrror:

pydantic_core._pydantic_core.ValidationError: 5 validation errors for SimpleRomSchema
files.0
  Input should be a valid dictionary [type=dict_type, input_value='D2 (USA).m3u', input_type=str]
    For further information visit https://errors.pydantic.dev/2.8/v/dict_type
files.1
  Input should be a valid dictionary [type=dict_type, input_value='D2 (USA) (Disc 4).chd', input_type=str]
    For further information visit https://errors.pydantic.dev/2.8/v/dict_type
files.2
  Input should be a valid dictionary [type=dict_type, input_value='D2 (USA) (Disc 3).chd', input_type=str]
    For further information visit https://errors.pydantic.dev/2.8/v/dict_type
files.3
  Input should be a valid dictionary [type=dict_type, input_value='D2 (USA) (Disc 2).chd', input_type=str]
    For further information visit https://errors.pydantic.dev/2.8/v/dict_type
files.4
  Input should be a valid dictionary [type=dict_type, input_value='D2 (USA) (Disc 1).chd', input_type=str]
    For further information visit https://errors.pydantic.dev/2.8/v/dict_type

To Reproduce

Add a multi disc game to a platform in v3.4.0, like the following:

Scan the platform.

Update to v3.5.0 alpha 1.

Open that platform in the Romm frontend.

Expected behavior

The platform's game list should load without error.

Screenshots

Desktop (please complete the following information):

• OS: macOS
• Browser Chrome
• Version 127.0.6533.120

Additional Context

_romm_logs (1).txt

[sargunv]

Some detail on the cause: the files column on the roms table used to be a list[str], but now it's a list[RomFile]. However, in my database, ~47 rom records still have strings instead of objects:

select json_type(json_extract(files, "$[0]")) as type, count(*)
from roms
group by type

type	count(*)
null	1608
OBJECT	565
STRING	47

I'm not sure why 47 records failed to convert to object, or how to force them to convert (short of manually updating the db records)

[sargunv]

Triggering a new scan of the affected platforms fixes the bad data and resolves the error.

select json_type(json_extract(files, "$[0]")) as type, count(*)
from roms
group by type

type	count(*)
null	1282
OBJECT	938

Eventually, after re-scanning all platforms, null came down to zero too:

type	count(*)
OBJECT	2220

[gantoine]

Thanks for investigating this! I was about to add that triggering any scan will fix the files array, and that the latest alpha release should trigger a scan on startup (through a migration). In any case we'll add a note in the release notes to manually run a scan if it doesn't trigger automatically on upgrade.

BTW if you're interested in testing future pre-releases, there's a closed Alpha Testers group on our Discord. We'd love to have you join it! https://discord.gg/PDGPX6tZ