Summary:
This is an incremental step in granular access control. Using
a temporary `{colIds: '~o structure'}` representation in the
`_grist_ACLResources` table, the document structure can be set
to be controlled by owners only.
Test Plan: added test
Reviewers: dsagal
Reviewed By: dsagal
Differential Revision: https://phab.getgrist.com/D2613
Summary:
This makes it possible to serve a table or tables only to owners.
* The _grist_ACLResources table is abused (temporarily) such that rows of the form `{colId: '~o', tableId}` are interpreted as meaning that `tableId` is private to owners.
* Many websocket and api endpoints are updated to preserve the privacy of these tables.
* In a document where some tables are private, a lot of capabilities are turned off for non-owners to avoid leaking info indirectly.
* The client is tweaked minimally, to show '-' where a page with some private material would otherwise go.
No attempt is made to protect data from private tables pulled into non-private tables via formulas.
There are some known leaks remaining:
* Changes to the schema of private tables are still broadcast to all clients (fixable).
* Non-owner may be able to access snapshots or make forks or use other corners of API (fixable).
* Changing name of table makes it public, since tableId in ACLResource is not updated (fixable).
Security will require some work, the attack surface is large.
Test Plan: added tests
Reviewers: dsagal
Reviewed By: dsagal
Differential Revision: https://phab.getgrist.com/D2604
