Version 7 (modified by 14 years ago) ( diff ) | ,
---|
Table of Contents
BluePrint for Authorization (alternative version)
General model
Authorization is implemented for the following methods:
- module access
- controller access
- table access (create/read/update/delete and custom method)
- record access (create/read/update/delete and custom method)
Authorization policy is implemented as:
- if a method is not restricted, then it is accessible for everyone
- if a method is restricted, then permission must be explicitly granted, otherwise it is denied (Allow=>Deny order)
Permissions are assigned to roles (not to individual users):
- roles are stored in auth_group
- admin role is auth_group 1 (cannot be modified)
- membership in the admin role overrides any restrictions everywhere
- roles are assigned to users by auth_membership
- this can happen either through admin UI or implicitly (no admin interaction)
- it must be possible to log this
- additional roles can be created after deployment
- this will usually happen implicitly, i.e. not through admin UI
- does not require a generic UI solution
- roles of the actual user are re-read from the DB and stored in the session once per HTTP request
- caching of this re-reading needs a proper method for cache invalidation on update notification
- do not implement caching unless it really makes us performance problems
There are two pseudo-roles for record access:
- author (=the author of the record)
- editor (=the last author of the record)
Methods
Denial of access:
- a method shn_unauthorized() realizes error notification and redirection as appropriate
- non-interactive modes:
- raise a HTTP error and a JSON error message
- DO NOT REDIRECT!
- interactive modes, one of:
- redirect (e.g. to login) and and display an error message on the target page (acceptable)
- raise a HTTP error and display an error page, provide redirection options from the error page (more RESTful)
- shn_unauthorized() takes an optional error message as argument
Module/Controller access:
- access can be restricted inside the controllers using:
- shn_has_role(role_name) which refers to the current user
- shn_has_role() tests can be combined by and, or and not
Table/Record access:
- table/record access can be restricted by:
- shn_permit(table, method, role, id=None) adds role to the list of permitted roles for method on table/record
- shn_deny(table, method, role, id=None) removes role from the list of permitted roles for method on table/record
- shn_restrict(table, method, role, id=None) replaces the list of permitted roles for method on table/record with [role]
- table/record access permission is tested by:
- shn_permitted(table, method, id=None), which returns True/False refering to the current user
- record restrictions override table permissions
- table restrictions override record permissions
Note:
See TracWiki
for help on using the wiki.