auth-jwt-server

Basic JWT server for Server State servers (cf. https://github.com/server-state/simple-server)

Usage

Installing and importing the module

Install the server with npm install @server-state/auth-jwt-server and import it with

const JWT = require('@server-state/auth-jwt-server');

Instantiating the JWT server instance

JWT is now an imported class. Therefore, you can use

const jwtServer = new JWT(config);

to instantiate a new instance to use with your server.

Config

The config consists of multiple required and optional fields:

Required config fields

• issuerName: string - the name of the token's issuer. Required for multi-server setups
• getUsersGroups: (username: string) => Promise<string[]> - a function that determines (and resolves with an array of) the user groups the passed user has access to.
• authenticate: (username: string, password: string) => Promise<boolean> - a function that checks users credentials. Returns a Promise<boolean> that resolves to true if the credentials are valid and false if they are not.

Optional config fields

• privateKey: string - the RS256 private key. Gets generated if none is provided; If provided, publicKey becomes a required field.
• publicKey: string - the RS256 public key. Gets generated if none is provided; If provided, privateKey becomes a required field.

Setting up the authentication route

Use

jwt.setup(router, '/auth/jwt');

where router is your express router to set up the route /auth/jwt as API endpoint for authentication (use .

This sets up

POST /auth/jwt

which returns a JSON string of the users token on success, HTTP 401 if the credentials couldn't be verified and HTTP 400 if either username or password weren't specified in the body.

Using the auth module in your server

To finally use the module in your server, you need to access it in your ServerBase config's isAuthorized. This is very dependent on your personal setup, but one basic example could look something like this:

isAuthorized: (req, authorizedGroups) => {
  const currentUsersGroups = jwt.getAuthorizedGroups(req.header('Authorization'));
  
  for (const group of authorizedGroups) {
    if (group === 'guest' || currentUsersGroups.includes(group)) {
      return true;
    }
  }
  
  return false;
}