AccessControl: Implement a way to register fixed roles (#35641)

* AccessControl: Implement a way to register fixed roles

* Add context to register func

* Use FixedRoleGrantsMap instead of FixedRoleGrants

* Removed FixedRoles map to sync.map


* Wrote test for accesscontrol and provisioning

* Use mutexes+map instead of sync maps

* Create a sync map struct out of a Map and a Mutex

* Create a sync map struct for grants as well

* Validate builtin roles

* Make validation public to access control

* Handle errors consistently with what seeder does

* Keep errors consistant amongst accesscontrol impl

* Handle registration error

* Reverse the registration direction thanks to a RoleRegistrant interface

* Removed sync map in favor for simple maps since registration now happens during init

* Work on the Registrant interface

* Remove the Register Role from the interface to have services returning their registrations instead

* Adding context to RegisterRegistrantsRoles and update descriptions

* little bit of cosmetics

* Making sure provisioning is ran after role registration

* test for role registration

* Change the accesscontrol interface to use a variadic

* check if accesscontrol is enabled

* Add a new test for RegisterFixedRoles and fix assign which was buggy

* Moved RegistrationList def to roles.go

* Change provisioning role's description

* Better comment on RegisterFixedRoles

* Correct comment on ValidateFixedRole

* Simplify helper func to removeRoleHelper

* Add log to saveFixedRole and assignFixedRole

Co-authored-by: Vardan Torosyan <vardants@gmail.com>
Co-authored-by: Jeremy Price <Jeremy.price@grafana.com>

pkg/api/http_server.go

@@ -117,8 +117,7 @@ func (hs *HTTPServer) Init() error {
 
 	hs.macaron = hs.newMacaron()
 	hs.registerRoutes()
-
-	return nil
+	return hs.declareFixedRoles()
 }
 
 func (hs *HTTPServer) AddMiddleware(middleware macaron.Handler) {