Registries

The domain declaration fixes the names, arities and roles that a policy may use. This is the JavaScript counterpart of the registry concept, not a separate place to add facts for each request.

Domain definition

registerDomain({name, predicates, atoms}) submits a complete declaration. The engine copies predicate names and policy atoms at registration. Repeated compatible registrations follow the C registry contract; close() does not promise to unregister a domain.

The shipped TypeScript declaration describes the input as Domain:

interface Domain {
  name: string
  predicates: { name: string; arity: number; flags: number }[]
  atoms?: string[]
}

Predicate kind flags

PredKind.EDB, IDB, QUERY, and POLICY_FACT describe the same origins and query permission as the public C API. Combine an origin with QUERY when it may be queried. A rule head must be IDB. Source facts require POLICY_FACT.

The explicit atoms list authorizes quoted constants written in policy source. A string supplied only through EDB input needs no atom declaration. The wrapper never infers atoms or enables permissive loading silently.

Example — document access

pg.registerDomain({
  name: 'access',
  predicates: [
    { name: 'safe', arity: 1, flags: PredKind.EDB },
    { name: 'allow', arity: 1, flags: PredKind.IDB | PredKind.QUERY },
  ],
  atoms: [],
})

safe/1 receives request facts, while the policy derives allow/1. The policy allow(X) :- safe(X). uses no quoted source constant, so its atoms list is empty. A value such as 'alice' passed later to addFacts() remains runtime data; it does not have to appear here.