Assets stuck in `Pending` validation state

[jjnesbitt]

The most recent example of this is #1473, but this has been occurring for a while. For some reason, assets find themselves stuck in a Pending state, never being updated. The only place this is updated is the validate_asset_metadata function, which is run within a task, and that is only ever called at the end of the calculate_sha256 task.

I'm not sure exactly what the cause of the disconnect is, nor if it's feasible to address consistently. One thing we could do to make sure assets are eventually validated is to run a scheduled task which would run validate_asset_metadata on any PENDING assets.

[satra]

another example: https://dandiarchive.org/dandiset/000243 (seems to also be a zarr asset).

[satra]

+1 to scheduled tasks (several use cases of those that i can think of).

[dandibot]

🚀 Issue was released in v0.3.48 🚀

[satra]

this is still happening - see: https://dandiarchive.org/dandiset/000108/

[satra]

while we are at it, it would be good to know when asset started validating in the message.