How do I bind this adapter, and what mechanism answers each rule shape? For an adopter whose rules are Elixir modules.
Mediate.Rbac decides from a policy module the application compiles. Nothing runs beside the application, a deploy is a policy version, and revocation is one commit.
How to bind
The configuration entry is the bare module, adapter: Mediate.Rbac. After the configuration boots, bind the policy and the repo, then publish the version. Mediate.Rbac.Binding has the options.
{:ok, _binding} = Mediate.Rbac.Binding.bind(policy: MyApp.Roles, repo: MyApp.Repo)
{:ok, _event} = Mediate.Rbac.publish()The declarations
A policy module is use Mediate.Rbac.Policy, and its moduledoc has the options in full.
role name, permissionsis one row of the role table.object Schema do ... endnames a protected schema and its clauses.grant name, RelationshipSchemaholds a role on a row through the relationship the schema declares, withon:,role:,as:, orthrough:where the declaration is not enough.predicate name, &Module.function/2is a function of the subject and the environment that returns adynamicover the row or a boolean, limited to some operations withonly:.usetakesversion:,author:, andapproval:.
The rule allows an operation on a row when any grant holds a role that permits it and every applicable predicate holds.
Mechanism per rule shape
| Rule shape | Mechanism |
|---|---|
| A role held on a row | a grant through the relationship schema, with through: where the relationship is one or more hops away |
| A test on the subject or the row | a predicate that returns a dynamic, read at the call from the environment the port stamped |
| A rule over a whole type | the same clauses composed into the dynamic that scope returns, so a scoped query and a checked row agree |
| A write gate | the role table alone. The seam refuses the write itself when no decision for the operation exists |
What this adapter decided
- Predicates return a
dynamic, and the adapter puts it in the query. A predicate that loads the row and answers in Elixir was the alternative. One query answerscheckandscopealike, so the two cannot disagree. - The role table is declared data. A function per role was the alternative. Data is what the access review reports and what the version hashes.
- The version is the commit the application names, and the content is the rule modules' hash and the role table. The source text was the alternative, and a hash is what a reviewer compares.
Revocation latency has one component, commit. A write that revokes is visible to the next query.