uAccess

uAccess is a lightweight implementation of access control tools, supporting both role-based access control (RBAC) and access control lists (ACL).

The JavaScript implementation is designed to be usable in conjunction with its PHP counterpart.

Factory

All objects in the uAccess tool can be created using the Factory.

In the browser, the uAccess object is namespaced and can be instantiated the following way:

var uAccess = new Mingos.uAccess.Factory();

Whereas when used in the context of Node.js, it's not namespaced and is created like this:

var ua = require("mingos-uaccess");
var uAccess = new ua.Factory();

RBAC

var rbac = uAccess.rbac();

The Rbac object stores and fetches roles. It has no other functions.

Creating roles

var lumberjack = uAccess.role("lumberjack");

The role can then be added to Rbac:

rbac.addRole(lumberjack);

Roles can also be created directly in Rbac, without instantiating them manually:

rbac.addRole("lumberjack");

Creating role relationships

Roles can have parent/child relationships, but unlike in a regular tree structure, a pparent can have many children AND a child can have many parents.

Roles can be added to each other via the Role#addSubordinate and Role#addSuperior functions:

var minstrel = uAccess.role("minstrel"),
    sirRobin = uAccess.role("sir robin"),
    arthur = uAccess.role("king arthur");
sirRobin
    .addSubordinate(minstrel)
    .addSuperior(arthur);

Once the hierarchy is set, the permissions will carry on from children to parents.

Granting permissions

Permissions are granted (or denied) to roles using Role.permissions#grant and Role.permissions#deny functions.

minstrel.permissions.grant("sing");
sirRobin.permissions.deny("sing").grant("flee");
arthur.permissions.grant("slay rabbit");

In the above example, we grant the minstrel a permission, but deny it to its direct superior, sirRobin. The denied permission is carried over to the next superior in the chain, arthur. Likewise, sirRobin is granted permission to flee and arthur is allowed to flee as well, though minstrel is not. Finally, only arthur is allowed to slay the vile beast rabbit of Caerbannog.

It isn't necessary to keep references to all roles in order to grant or deny permissions. If the roles are added to Rbac, they can be fetched by name:

rbac.getRole("minstrel").permissions.grant("sing");

Checking permissions

Permissions can be checked using the Role#isGranted function.

minstrel.isGranted("sing"); //true
minstrel.isGranted("flee"); //false
minstrel.isGranted("slay rabbit"); // false

Again, it's a much better idea to use the Rbac object for role fetching:

rbac.getRole("minstrel").isGranted("sing");

ACL

var identity = uAccess.identity();

Access control is based on an individual identity rather than a more generic role. An Identity object is used to store permissions in the same way a Role is, but there are no subordinate/superior roles or identities to check when determining if access to a permission is granted or denied.

Granting permissions

Granting and denying permissions is done via the Identity.permissions#grant and Identity.permissions#deny functions.

identity.permissions
    .grant("flee")
    .deny("sing");

Checking permissions

As with roles, checking permissions is done with the Identity#isGranted function.

identity.isGranted("sing"); // false
identity.isGranted("flee"); // true
identity.isGranted("slay rabbit"); // false

RBAC + ACL

It is possible to combine both approaches and use role-based access along with an access control list. This is achieved by adding roles to an identity.

identity.addRole(sirRobin);

From this point onwards, the identity will report that it's granted the same permissions as the role sirRobin. Since sirRobin has subordinate roles, the identity will also inherit permissions from those roles.

API reference

Factory

identity()

Construct a new Identity instance

• returns Identity

permissions()

Construct a new Permissions instance

• returns Permissions

rbac()

Construct a new Rbac instance

• returns Rbac

role(roleName)

Construct a new Role instance

• parametre roleName (String) - name for the role
• returns Role

Rbac

addRole(role, overwrite)

Add a role to RBAC.

• parametre role (String or Role) - either role name or a role object
• parametre overwrite (Boolean) - flag indicating if the role should be overwritten in case there's already a role with the matching name. Defaults to false.
• returns Rbac - provides a fluent interface

getRole(roleName)

Fetch a given role. The role must be added to Rbac first.

• parametre roleName (String) - name of the role to fetch
• returns Role

hasRole(roleName)

Check whether the role with a given name is already defined.

• parametre roleName (String) - name of the role to fetch
• returns Boolean

hydrate(input)

Hydrate the Rbac object using a serialised object.

• parametre input (Object) - serialised object containing roles and their relationships, as returned by Rbac#serialise.
• returns Rbac - provides a fluent interface

roles

Roles defined in the object.

• type Object

serialise()

Serialise the defined roles to a plain object.

• returns Object

Role

addSubordinate(subordinate)

Add a subordinate role.

• parametre subordinate (Role) - role that will be the current role's subordinate
• returns Role - provides a fluent interface

addSuperior(superior)

Add a superior role.

• parametre superior (Role) - role that will be the current role's superior
• returns Role - provides a fluent interface

hasSubordinate(role, direct)

Check if the role has a subordinate role.

• parametre role (Role|String) - either a Role object or a string containing the role name
• parametre direct (Boolean) - flag indicating whether only direct subordinates should be checked (true) or all subordinate roles, including subordinates of subordinates (false). Defaults to false.
• returns Boolean

hasSuperior(role, direct)

Check if the role has a superior role.

• parametre role (Role|String) - either a Role object or a string containing the role name
• parametre direct (Boolean) - flag indicating whether only direct superiors should be checked (true) or all superior roles, including superiors of superiors (false). Defaults to false.
• returns Boolean

hydrate(input, rbac)

Hydrate the role using a serialised object.

• parametre input (Object) - output of Role#serialise.
• parametre rbac (Rbac) - the Rbac object containing the role and its superior/subordinate roles
• returns Role - provides a fluent interface

isGranted(permission)

Check if the role has access to a permission. Subordinate roles are checked if the permission is not found on the role in question.

• parametre permission (String) - permission name
• returns Boolean

name

The name of the role.

• type String

permissions

Role permissions

• type Permissions

serialise()

Serialise the role to a plain object.

• returns Object

subordinates

Role's subordinate roles.

• type Object

superiors

Role's superior roles.

• type Object

Identity

addRole(role)

Add a role to the identity.

• parametre role (uAccess.Role) - role to be added
• returns Identity - provides a fluent interface

hasRole(role)

Check if the identity has a role.

• parametre roleName (String|uAccess.Role) - the role or role name to check
• returns Boolean

hydrate(input, rbac)

Build the identity based on the serialised output of Identity#serialise.

• parametre input (Object) - output of Identity#serialise
• parametre rbac (Rbac) - an instance of Rbac that will provide the roles for the identity
• returns Identity - provides a fluent interface

isGranted(permission)

Check if the identity has access to a permission. The permissions added directly to the identity (ACL) have precedence over permissions added to identity roles (RBAC).

• parametre permission (String) - name of the permission to check

permissions

Identity permissions

• type Permissions

roles

Identity roles

• type Role[]

serialise()

Serialise the identity to a plain object

• returns Object

setRoles(roles)

Clear the roles already assigned to the identity and add a new set.

• parametre roles (uAccess.Role[]) - array of Role objects that will become the identity roles
• returns Identity - provides a fluent interface

Permissions

The Permissions objects are present in Role and Identity objects as Role.permissions and Identity.permissions, respectively.

deny(permission)

Deny access to a resource

• parametre permission (String) - permission name
• returns Permissions - provides a fluent interface

get(permission)

Get the value of a given permission

• parametre permission (String) - permission name
• returns Boolean

grant(permission)

Grant access to a resource

• parametre permission (String) - permission name
• returns Permissions - provides a fluent interface

has(permission)

Check if a given permission is set

• parametre permission (String) - permission name
• returns Boolean

set(permissions)

Replace any defined permissions with a new set

• parametre permissions (Object) - object with permission names as keys and Boolean values
• returns Permissions - provides a fluent interface