Modèle de priorité
Casbin supports loading policies with priority.
Load Policy with Implicit Priority
It's quite simple: the order determines the priority; policies that appear earlier have higher priority.
model.conf :
[policy_effect]
e = priorité(p.eft) || nier
Load Policy with Explicit Priority
Voir aussi : casbin#550
A smaller priority value indicates a higher priority. If there's a non-numerical character in the priority, it will be placed last instead of throwing an error.
The conventionally used priority token name in the policy definition is "priority". To use a custom one, you need to invoke e.SetFieldIndex() and reload the policies (see the full example on TestCustomizedFieldIndex).
model.conf :
[policy_definition]
p = customized_priority, sub, obj, act, eft
Golang code example:
e, _ := NewEnforcer("./example/priority_model_explicit_customized.conf",
"./example/priority_policy_explicit_customized.csv")
// Due to the customized priority token, the enforcer fails to handle the priority.
ok, err := e.Enforce("bob", "data2", "read") // the result will be `true, nil`
// Set PriorityIndex and reload
e.SetFieldIndex("p", constant.PriorityIndex, 0)
err := e.LoadPolicy()
if err != nil {
log.Fatalf("LoadPolicy: %v", err)
}
ok, err := e.Enforce("bob", "data2", "read") // the result will be `false, nil`
Currently, explicit priority only supports AddPolicy & AddPolicies. If UpdatePolicy has been called, you shouldn't change the priority attribute.
model.conf :
[request_definition]
r = sub, obj, act
[policy_definition]
p = priority, sub, obj, act, eft
[role_definition]
g = _, _
[policy_effect]
e = priority(p.eft) || deny
[matchers]
m = g(r.sub, p.sub) && r.obj == p.obj && r.act == p.act
Politique.csv
p, 10, data1_deny_group, data1, read, deny
p, 10, data1_deny_group, data1, write, deny
p, 10, data2_allow_group, data2, read, allow
p, 10, data2_allow_group, data2, write, allow
p, 1, alice, data1, write, allow
p, 1, alice, data1, read, allow
p, 1, bob, data2, read, deny
g, bob, data2_allow_group
g, alice, data1_deny_group
Requête:
alice, data1, write --> true // because `p, 1, alice, data1, write, allow` has the highest priority
bob, data2, read --> false
bob, data2, write --> true // because bob has the role of `data2_allow_group` which has the right to write data2, and there's no deny policy with higher priority
Politique de charge avec priorité basée sur le rôle et la hiérarchie des utilisateurs
La structure héritée des rôles et des utilisateurs ne peut être que de multiples arborescences et non des graphiques. If a user has multiple roles, you have to make sure the user has the same level in different trees. If two roles have the same level, the policy (associated with the role) that appeared earlier has higher priority. For more details, also see casbin#833 and casbin#831.
model.conf:
[request_definition]
r = sub, obj, act
[policy_definition]
p = sub, obj, act, eft
[role_definition]
g = _, _
[policy_effect]
e = subjectPriority(p.eft) || deny
[matchers]
m = g(r.sub, p.sub) && r.obj == p.obj && r.act == p.act
Politique.csv
p, root, data1, read, deny
p, admin, data1, read, deny
p, editor, data1, read, deny
p, subscriber, data1, read, deny
p, jane, data1, read, allow
p, alice, data1, read, allow
g, admin, root
g, editor, admin
g, subscriber, admin
g, jane, editor
g, alice, subscriber
Requête:
jane, data1, read --> true // because jane is at the bottom, her priority is higher than that of editor, admin, and root
alice, data1, read --> true
The role hierarchy looks like this:
role: root
└─ role: admin
├─ role editor
│ └─ user: jane
│
└─ role: subscriber
└─ user: alice
The priority automatically looks like this:
role: root # auto priority: 30
└─ role: admin # auto priority: 20
├─ role: editor # auto priority: 10
└─ role: subscriber # auto priority: 10