# auth-server-helper

version: 2.0.0

customizable and simple authentication

## Installation

npm:

> npm i --save auth-server-helper

yarn:

> yarn add auth-server-helper

## Usage

### 1. put a gateway in front of the routes you want to secure

```js
const {create_gateway} = require('@sapphirecode/auth-server-helper');

const gateway = create_gateway({
  redirect_url: '/auth',
  cookie_name: 'auth_cookie', // if defined, access tokens will be read from this cookie
});

// express
app.use(gateway);

// node http
http.createServer((main_req, main_res) =>
  gateway(main_req, main_res, (req, res) => {
    // your request handler
  });
);
```

the gateway will forward any authorized requests to the next handler and
redirect all others to the specified url

### 2. creating the auth endpoint

```js
const {create_auth_handler} = require('@sapphirecode/auth-server-helper');

const handler = create_auth_handler(
  async (req) => {
    if (req.user === 'foo' && req.password === 'bar')
      const {access_token_id, refresh_token_id} = await req.allow_access({
        access_token_expires_in: 600, // seconds until access tokens expire
        include_refresh_token: true, // should the answer include a refresh token? default: false
        refresh_token_expires_in: 3600, // seconds until refresh tokens expire (required if refresh tokens are generated)
        data: {user: 'foo'}, // additional custom data to include in the token
      });

    if (req.user === 'part' && req.password === 'baz')
      const part_id = await req.allow_part(
        60, // seconds until part_token expires
        'some_module', // next module handler (defined below)
        {foo: 'bar'} // custom data to attach to the token
      );

    // all allow_ functions return a token id, which can later be used to invalidate specific tokens from the server side

    req.deny();
  },
  {
    refresh: {
      /*...same options as allow_access */
    }, // define the behaviour of refresh tokens. Refresh tokens will not be accepted if this option is undefined
    modules: {
      some_module(req) {
        // request handlers for part_tokens

        // access custom data:
        const auth_data = req.request.connection.auth;
        auth_data.token_id; // token id
        auth_data.token_data; // custom data
        // the same works in handlers after the gateway, information is always stored in request.connection.auth
      },
    },
    cookie_name: 'auth_cookie', // if defined, access tokens will be stored in this cookie
  }
);

// express
app.use(handler);

// node http
// ... create server, on path /auth run the handler
handler(req, res);
```

after the auth handler, the request will be completed, no additional content
should be served here.

### Invalidating tokens after they are delivered to the client

```js
const {blacklist} = require('@sapphirecode/auth-server-helper');

blacklist.add_signature(token_id); // the token id is returned from any function that creates tokens
```

## License

MIT © Timo Hocker <timo@scode.ovh>