Prevents an accidental lockout of query preset documents. An "accidental
lockout" occurs when the user sets access control on a preset and
excludes themselves. This can happen in a variety of scenarios,
including:
- You select `specificUsers` without specifying yourself
- You select `specificRoles` without specifying a role that you are a
part of
- Etc.
#### How it works
To make this happen, we use a custom validation function that executes
access against the user's proposed changes. If those changes happen to
remove access for them, we throw a validation error and prevent that
change from ever taking place. This means that only a user with proper
access can remove another user from the preset. You cannot remove
yourself.
To do this, we create a temporary record in the database that we can
query against. We use transactions to ensure that the temporary record
is not persisted once our work is completed. Since not all Payload
projects have transactions enabled, we flag these temporary records with
the `isTemp` field.
Once created, we query the temp document to determine its permissions.
If any of the operations throw an error, this means the user can no
longer act on them, and we throw a validation error.
#### Alternative Approach
A previous approach that was explored was to add an `owner` field to the
presets collection. This way, the "owner" of the preset would be able to
completely bypass all access control, effectively eliminating the
possibility of a lockout event.
But this doesn't work for other users who may have update access. E.g.
they could still accidentally remove themselves from the read or update
operation, preventing them from accessing that preset after submitting
the form. We need a solution that works for all users, not just the
owner.
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