loopback/lib/models/role.js

// Role model
var RoleSchema = {
    id: {type: String, required: true},
    name: {type: String, required: true}, // The name of a role
    description: String,
    roles: [String], // A role can be an aggregate of other roles
    users: [String], // A role contains a list of users
    created: Date,
    lastUpdated: Date
}