Part 1:What is role and rights?
Role rights implementation is an important part of any software. Role is a position of responsibility and every responsibility enjoys some rights given to them. There may be some common rights between a few roles and some rights may strictly belong to a specific role.
Rights are Urls that a role is authorized to access. It is thus necessary to create a collection in DB storing information of rights to a role. We have role collection schema as
const mongoose = require('mongoose'); const Schema = mongoose.Schema; const RoleSchema = new Schema({ roleId:{ type:String, unique:true, required:[true,"Role Id required"] }, type:{ type:String, unique:true, required:[true,"Role type is required"] }, rights:[{ name: String, path: String, url: String }] }); module.exports = Role = mongoose.model('role',RoleSchema); Now, remember every role that is supposed to exist is in Role collection and of above schema type.
In schema rights array of the object we see the object has keys:
- name(for the name of URL like “set-username”)
- path(for base path hit “/users/”)
- url(requested URL or complete path “/users/set-username”)
Thus if a user with role user has right to change username then he can hit URL /users/set-username.However a wanderer will not be able to access this url. A higher role like admin & superadmin should logically have access to all lower role rights(URLs).
Role in real application are:-
- Wanderer (Someone who is just visiting our site. He should be able to access all public routes. Simple URLs/Public URLs accessible to all thus need not make a separate role for this as it is not any authenticated right.)
- Guest (Someone who has registered but not verified say email not verified).
- User (Someone who has his verified email)
- Admin (Made an Admin by SuperAdmin after verifying.he enjoy most of the rights)
- Superadmin (Master of application.He enjoy some more sophisticated rights.More rights then admin)
Till now we have understood what exactly is right and how it is mapped to a role.
Part 1.5: Registered Urls/Config Urls
Here we have a file called registeredUrls.js which is like:
module.exports = { // globally accessible simple: { "/":[""], '/users/':["login","register"], }, auth:{ //admin level enpoint '/admin/': ['load-users' , 'set-new-password', 'delete-user'], '/teacher/': ["add-teacher", "delete-teacher", "edit-teacher"], '/student/': [ "add-student", "delete-student", "edit-student", "test-result" ], // common user enpoint '/test/': ["view-test", "submit-test"], '/profile/': [ 'change-username', 'update-profile-data', 'set-new-password', 'upload-pic', 'update-social-links' ], '/teacher/':['load-teacher'], '/student/':['load-student'] } Similarly confgUrls.js
const configUrls= { '/roles/': [ 'get-rights', 'create', 'update-rights', 'load', 'delete', 'assign' ] } module.exports = configUrls; Part 2:Creating SuperAdmin
This is the most essential part of the application. Whenever the server starts for the first time or restarts/reboots this step occurs. In config/init.js follow the procedure:
- Load All simple URLs(public) and Auth Urls(admin & users) & super-admin-specific URLs into superAdminRights[].
- Then run a function to create a user with role superadmin if doesn’t exist.
- Get a Role of type:”superadmin” if found:replace its rights with new rights(superAdminRights).else:create Role of type :”superadmin” and then fill its rights(superAdminRights).
At the end of this function call, we are always sure that we have a superadmin in application with all its sophisticated URLs/rights initialized.
Part 3:Super-Admin-Specific-URLs
These are rights that are enjoyed by super admin only and must be maintained in a separate file in parallel to the registered URL file. These include URL rights which map routes used only by superadmin. Here we have routes to create role, load roles, get-rights for a roleId, update-rights for roleId/role type, assign-role to a user, delete a role.
For each user in code, we need to change their role from guest to the user(say after email verification). Or guest/user to admin by superadmin using assign-role URL. Then updating admin rights using route update-rights.
The process ensures that every role has A collection Document and filled rights there.
Part 4:Authenticator Middleware
This heart of our RBACS logic. Here we use a middleware which follows the process:
// get all the URLs/endpoints in the system const URLS = require("./registeredUrls"); // special endpoints const CONFIG_URLS = require("./configUrls"); // create array of all endpoints and separate them by auth flows // simple urls doesn't need any auth flow const SIMPLE_URLS = []; // AUTH_URL and SUPER_URL need auth flow const AUTH_URLS = []; const SUPER_URLS = []; // the data-structure is { [rootURL]: [...subURLs..] } // traverse all registered paths of simple URLs // and make complete paths i.e `rootURL/subURL` for (const rootURL in URLS.simple) { const subURLs = URLS.simple[rootURL]; for (const subURL of subURLs) { // register all these in SIMPLE_URLS SIMPLE_URLS.push([rootURL, subURL].join("/")); } } // same with AUTH...register as AUTH_URLS for (const rootURL in URLS.auth) { const subURLs = URLS.auth[rootURL]; for (const subURL of subURLs) { AUTH_URLS.push([rootURL, subURL].join("/")); } } // same with CONFIG_URLS...register as SUPER_URLS for (const rootURL in CONFIG_URLS) { const subURLs = CONFIG_URLS[rootURL]; for (const subURL of subURLs) { SUPER_URLS.push([rootURL, subURL].join("/")); // push super URLS in AUTH_URLS also as they need auth flow AUTH_URLS.push([rootURL, subURL].join("/")); } } // By now we have an array of URLs // 1. Simple URLs don't need authentication flow SIMPLE_URLS // 2. Authentication required URLs need auth-token // 3. Config URLs are the highest roles URLs typically super admin // and have the same flow as Auth URL // in the node.js middleware callback const middleware = (req, res, next) => { // URL or endpoint or path requested const reqURL = req.url; // check where URL is const isAuthURL = AUTH_URLS.includes(reqURL); const isSimpleURL = SIMPLE_URLS.includes(reqURL); // auth URLs need auth flows if (isAuthURL) { // get token from header const token = getToken(req); // validate const isValidJWTToken = validateJWT(token); if (!token || !isValidJWTToken) { // send failed authentication response // !token missing token required login // !isValidJWTToken token is invalid or expired return; } // token is valid but we have to check if the session exists in DB const user_session = getUserSessionData(token); // If no session in DB means this token may be mischievously generated if (!user_session) { // the user token might be compromised return; } // now check if user_session.rights [] has requested URL // if requested URL is assigned is in array means // it is assigned that right/path const hasRightToPath = user_session.rights.includes(reqURL); if (!hasRightToPath) { // user doesn't have access to this path return; } // user has right to this path/endpoint/URL so let them do the thing return next(); } if (isSimpleURL) { return next(); // simple URL doesn't need any flow simply pass it down } // if it matched none means it isn't a registered path in the system return; } 
Top comments (0)