Scope Utils

This is a small collection of utility functions for AuthX scopes. These scopes are human-readable, fully OAuth2-compatible, and support both pattern matching and set algebra. Please visit the AuthX repo to see it in action.

Anatomy of a scope

Scopes are composed of 3 domains, separated by the : character:

AuthX:role.abc:read
|___| |______| |__|
  |      |       |
realm  resource  action

Each domain can contain segments, separated by the . character. Domain segments can be /[a-zA-Z0-9_]*/ strings or glob pattern identifiers * or **:

role.abc
role.*
**

Installation

Install with npm install --save scopeutils

Usage

Please see the tests for complete examples.

validate(scope: string): boolean

Validate that a scope is correctly formatted.

import { validate } from "scopeutils";
 
validate("realm:resource.identifier:action");
// => true
 
validate("realm:resource.***:action");
// => false

normalize(scope: string): string

• throws InvalidScopeError if the scope is invalid.

Normalize a scope into its simplest representation.

import { normalize } from "scopeutils";
 
normalize("realm:**.**:action");
// => 'realm:*.**:action'

simplify(collection: string[]): string[]

• throws InvalidScopeError if any scopes in collection are invalid.

Simplify the collection of scopes in collection by omiting any scopes that are a made redundant by another scope in the collection. All scopes in the returned collection are normalized.

import { simplify } from "scopeutils";
 
simplify(["realm:resource.*:action", "realm:**:action"]);
// => ['realm:**:action']

isEqual(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): boolean

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Check whether scopeOrCollectionA and scopeOrCollectionB are the same, ignoring redundant scopes.

import { getIntersection } from "scopeutils";
 
getIntersection(["realm:**:*"], ["realm:**:action", "realm:**:*"]);
// => true

isSuperset(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): boolean

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Check whether scopeOrCollectionA is equal to, or a superset of scopeOrCollectionB. This is appropriate for checking if a user can perform a particular action.

import { isSuperset } from "scopeutils";
 
isSuperset(["realm:**:*"], ["realm:**:action", "realm:**:*"]);
// => true

isStrictSuperset(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): boolean

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Check whether scopeOrCollectionA is a strict superset of scopeOrCollectionB.

import { isStrictSuperset } from "scopeutils";
 
isStrictSuperset(["realm:**:*"], ["realm:**:action", "realm:**:*"]);
// => false

isSubset(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): boolean

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Check whether scopeOrCollectionA is equal to, or a subset of scopeOrCollectionB.

import { isSubset } from "scopeutils";
 
isSubset(["realm:**:action", "realm:**:*"], ["realm:**:*"]);
// => true

isStrictSubset(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): boolean

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Check whether scopeOrCollectionA is a strict subset of scopeOrCollectionB.

import { isStrictSubset } from "scopeutils";
 
isStrictSubset(["realm:**:action", "realm:**:*"], ["realm:**:*"]);
// => false

getIntersection(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): string[]

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Get the intersection of scopeOrCollectionA and scopeOrCollectionB, returning a collection of scopes that represent all intersections, or every ability common to both inputs.

import { getIntersection } from "scopeutils";
 
getIntersection(["realm:resource.*:action.*"], ["realm:**:action.read"]);
// => ['realm:resource.*:action.read']

hasIntersection(scopeOrCollectionA: string[] | string, scopeOrCollectionB: string[] | string): string[]

• throws InvalidScopeError if any scopes in scopeOrCollectionA or scopeOrCollectionB are invalid.

Check whether scopeOrCollectionA and scopeOrCollectionB intersect. This is useful when checking if a user can perform any subset of the actions represented by the subject scope.

import { hasIntersection } from "scopeutils";
 
hasIntersection(["realm:resource.*:action.*"], ["realm:**:action.read"]);
// => true