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© 2017, Onur Yıldırım (@onury). MIT License.

Role and Attribute based Access Control for Node.js

Many RBAC (Role-Based Access Control) implementations differ, but the basics is widely adopted since it simulates real life role (job) assignments. But while data is getting more and more complex; you need to define policies on resources, subjects or even environments. This is called ABAC (Attribute-Based Access Control).

With the idea of merging the best features of the two (see this NIST paper); this library implements RBAC basics and also focuses on resource and action attributes.

Core Features

In order to build on more solid foundations, this library (v1.5.0+) is completely re-written in TypeScript.


with npm: npm i accesscontrol --save

with yarn: yarn add accesscontrol


const AccessControl = require('accesscontrol');
// or:
// import { AccessControl } from 'accesscontrol';

Basic Example

Define roles and grants one by one.

const ac = new AccessControl();
ac.grant('user')                    // define new or modify existing role. also takes an array.
    .createOwn('video')             // equivalent to .createOwn('video', ['*'])
  .grant('admin')                   // switch to another role without breaking the chain
    .extend('user')                 // inherit role capabilities. also takes an array
    .updateAny('video', ['title'])  // explicitly defined attributes

const permission = ac.can('user').createOwn('video');
console.log(permission.granted);    // —> true
console.log(permission.attributes); // —> ['*'] (all attributes)

permission = ac.can('admin').updateAny('video');
console.log(permission.granted);    // —> true
console.log(permission.attributes); // —> ['title']

Express.js Example

Check role permissions for the requested resource and action, if granted; respond with filtered attributes.

const ac = new AccessControl(grants);
// ...
router.get('/videos/:title', function (req, res, next) {
    const permission = ac.can(req.user.role).readAny('video');
    if (permission.granted) {
        Video.find(req.params.title, function (err, data) {
            if (err || !data) return res.status(404).end();
            // filter data by permission attributes and send.
    } else {
        // resource is forbidden for this user/role


You can create/define roles simply by calling .grant(<role>) or .deny(<role>) methods on an AccessControl instance.

// user role inherits viewer role permissions
// admin role inherits both user and editor role permissions
ac.grant('admin').extend(['user', 'editor']);
// both admin and superadmin roles inherit moderator permissions
ac.grant(['admin', 'superadmin']).extend('moderator');
// case #1
ac.grant('admin').extend('user') // assuming user role already exists

// case #2

// below results the same for both cases
const permission = ac.can('admin').createOwn('video');
console.log(permission.granted); // true

Notes on inheritance:

Actions and Action-Attributes

CRUD operations are the actions you can perform on a resource. There are two action-attributes which define the possession of the resource: own and any.

For example, an admin role can create, read, update or delete (CRUD) any account resource. But a user role might only read or update its own account resource.

Action Possession
Own The C|R|U|D action is (or not) to be performed on own resource(s) of the current subject.
Any The C|R|U|D action is (or not) to be performed on any resource(s); including own.

Note that own requires you to also check for the actual possession. See this for more.

Resources and Resource-Attributes

Multiple roles can have access to a specific resource. But depending on the context, you may need to limit the contents of the resource for specific roles.

This is possible by resource attributes. You can use Glob notation to define allowed or denied attributes.

For example, we have a video resource that has the following attributes: id, title and runtime. All attributes of any video resource can be read by an admin role:

ac.grant('admin').readAny('video', ['*']);
// equivalent to:
// ac.grant('admin').readAny('video');

But the id attribute should not be read by a user role.

ac.grant('user').readOwn('video', ['*', '!id']);
// equivalent to:
// ac.grant('user').readOwn('video', ['title', 'runtime']);

You can also use nested objects (attributes).

ac.grant('user').readOwn('account', ['*', '!']);

Checking Permissions and Filtering Attributes

You can call .can(<role>).<action>(<resource>) on an AccessControl instance to check for granted permissions for a specific resource and action.

const permission = ac.can('user').readOwn('account');
permission.granted;       // true
permission.attributes;    // ['*', '!']
permission.filter(data);  // filtered data (without

See express.js example.

Defining All Grants at Once

You can pass the grants directly to the AccessControl constructor. It accepts either an Object:

// This is actually how the grants are maintained internally.
let grantsObject = {
    admin: {
        video: {
            'create:any': ['*', '!views'],
            'read:any': ['*'],
            'update:any': ['*', '!views'],
            'delete:any': ['*']
    user: {
        video: {
            'create:own': ['*', '!rating', '!views'],
            'read:own': ['*'],
            'update:own': ['*', '!rating', '!views'],
            'delete:own': ['*']
const ac = new AccessControl(grantsObject);

... or an Array (useful when fetched from a database):

// grant list fetched from DB (to be converted to a valid grants object, internally)
let grantList = [
    { role: 'admin', resource: 'video', action: 'create:any', attributes: '*, !views' },
    { role: 'admin', resource: 'video', action: 'read:any', attributes: '*' },
    { role: 'admin', resource: 'video', action: 'update:any', attributes: '*, !views' },
    { role: 'admin', resource: 'video', action: 'delete:any', attributes: '*' },

    { role: 'user', resource: 'video', action: 'create:own', attributes: '*, !rating, !views' },
    { role: 'user', resource: 'video', action: 'read:any', attributes: '*' },
    { role: 'user', resource: 'video', action: 'update:own', attributes: '*, !rating, !views' },
    { role: 'user', resource: 'video', action: 'delete:own', attributes: '*' }
const ac = new AccessControl(grantList);

You can set grants any time...

const ac = new AccessControl();

...unless you lock it:

ac.lock().setGrants({}); // throws after locked


You can read the full API reference with lots of details, features and examples.
And more at the F.A.Q. section.




Clone original project:

git clone

Install dependencies:

yarn install

Add tests to relevant file under /test directory and run:

yarn build && yarn cover

Use included tslint.json and editorconfig for style and linting.
Travis build should pass, coverage should not degrade.