[feature request] Run FileField storage callable during runtime and not during buildtime

[Vasanth]

If the storage callable can be invoked during runtime similar to the "upload_to", it can allow us to choose the storage to use dynamically. This is particularly helpful for SaaS services which prefer maintaining independent storages per client/subdomain.

Something like, the following snippet where local_state.tenant is threading local() which holds the name of the tenant for each request

def tenant_storage(instance, filename):
    tenant = getattr(local_state, "tenant", "default")
    return storages[tenant]

[Natalia Bidart]

Accepting since I agree that there is no need to evaluate the callable at field creation time, and that there is value in having consistency between upload_to and storage.

[Natalia Bidart]

Actually on a second thought, this may be best decided in the forum to have a wider audience. Posting there!

[Mariusz Felisiak]

Also, this is a ​documented behavior so we cannot change it without the deprecation path:

"Your callable will be evaluated when your models classes are loaded, and must return an instance of Storage."

[Natalia Bidart]

Replying to Mariusz Felisiak:

Also, this is a ​documented behavior so we cannot change it without the deprecation path:

"Your callable will be evaluated when your models classes are loaded, and must return an instance of Storage."

-1 from me.

Good point, I'll close for now as wontfix, then if there is enough traction in the forum we can revisit. Thanks!