JWT Authentication for WP REST API

Description

This plugin seamlessly extends the WP REST API, enabling robust and secure authentication using JSON Web Tokens (JWT). It provides a straightforward way to authenticate users via the REST API, returning a standard JWT upon successful login.

Key features of this free version include:

• Standard JWT Authentication: Implements the industry-standard RFC 7519 for secure claims representation.
• Simple Endpoints: Offers clear /token and /token/validate endpoints for generating and validating tokens.
• Configurable Secret Key: Define your unique secret key via wp-config.php for secure token signing.
• Optional CORS Support: Easily enable Cross-Origin Resource Sharing support via a wp-config.php constant.
• Developer Hooks: Provides filters (jwt_auth_expire, jwt_auth_token_before_sign, etc.) for customizing token behavior.

JSON Web Tokens are an open, industry standard method for representing claims securely between two parties.

For users requiring more advanced capabilities such as multiple signing algorithms (RS256, ES256), token refresh/revocation, UI-based configuration, or priority support, consider checking out JWT Authentication PRO.

Support and Requests: Please use GitHub Issues. For priority support, consider upgrading to PRO.

JWT Authentication PRO

Elevate your WordPress security and integration capabilities with JWT Authentication PRO. Building upon the solid foundation of the free version, the PRO version offers advanced features, enhanced security options, and a streamlined user experience:

• Easy Configuration UI: Manage all settings directly from the WordPress admin area.
• Token Refresh Endpoint: Allow users to refresh expired tokens seamlessly without requiring re-login.
• Token Revocation Endpoint: Immediately invalidate specific tokens for enhanced security control.
• Customizable Token Payload: Add custom claims to your JWT payload to suit your specific application needs.
• Granular CORS Control: Define allowed origins and headers with more precision directly in the settings.
• Rate Limiting: Protect your endpoints from abuse with configurable rate limits.
• Audit Logs: Keep track of token generation, validation, and errors.
• Priority Support: Get faster, dedicated support directly from the developer.

Upgrade to JWT Authentication PRO Today!

Free vs. PRO Comparison

Here’s a quick look at the key differences:

• Basic JWT Authentication: Included (Free), Included (PRO)
• Token Generation: Included (Free), Included (PRO)
• Token Validation: Included (Free), Included (PRO)
• Token Refresh Mechanism: Not Included (Free), Included (PRO)
• Token Revocation: Not Included (Free), Included (PRO)
• Token Management Dashboard: Not Included (Free), Included (PRO)
• Analytics & Monitoring: Not Included (Free), Included (PRO)
• Geo-IP Identification: Not Included (Free), Included (PRO)
• Rate Limiting: Not Included (Free), Included (PRO)
• Detailed Documentation: Basic (Free), Comprehensive (PRO)
• Developer Tools: Not Included (Free), Included (PRO)
• Premium Support: Community via GitHub (Free), Priority Direct Support (PRO)

REQUIREMENTS

WP REST API V2

This plugin was conceived to extend the WP REST API V2 plugin features and, of course, was built on top of it.

So, to use the wp-api-jwt-auth you need to install and activate WP REST API.

PHP

Minimum PHP version: 7.4.0

PHP HTTP Authorization Header Enable

Most shared hosting providers have disabled the HTTP Authorization Header by default.

To enable this option you’ll need to edit your .htaccess file by adding the following:

RewriteEngine on
RewriteCond %{HTTP:Authorization} ^(.*)
RewriteRule ^(.*) - [E=HTTP_AUTHORIZATION:%1]

WPENGINE

For WPEngine hosting, you’ll need to edit your .htaccess file by adding the following:

SetEnvIf Authorization "(.*)" HTTP_AUTHORIZATION=$1

See https://github.com/Tmeister/wp-api-jwt-auth/issues/1 for more details.

CONFIGURATION

Configure the Secret Key

The JWT needs a secret key to sign the token. This secret key must be unique and never revealed.

To add the secret key, edit your wp-config.php file and add a new constant called JWT_AUTH_SECRET_KEY:

define('JWT_AUTH_SECRET_KEY', 'your-top-secret-key');

You can generate a secure key from: https://api.wordpress.org/secret-key/1.1/salt/

Looking for easier configuration? JWT Authentication PRO allows you to manage all settings through a simple admin UI.

Configure CORS Support

The wp-api-jwt-auth plugin has the option to activate CORS support.

To enable CORS Support, edit your wp-config.php file and add a new constant called JWT_AUTH_CORS_ENABLE:

define('JWT_AUTH_CORS_ENABLE', true);

Finally, activate the plugin within your wp-admin.

Namespace and Endpoints

When the plugin is activated, a new namespace is added:

/jwt-auth/v1

Also, two new endpoints are added to this namespace:

Endpoint | HTTP Verb
/wp-json/jwt-auth/v1/token | POST
/wp-json/jwt-auth/v1/token/validate | POST

Need more functionality? JWT Authentication PRO includes additional endpoints for token refresh and revocation.

USAGE

/wp-json/jwt-auth/v1/token

This is the entry point for JWT Authentication.

It validates the user credentials, username and password, and returns a token to use in future requests to the API if the authentication is correct, or an error if authentication fails.

Sample Request Using AngularJS

(function() {
  var app = angular.module('jwtAuth', []);

  app.controller('MainController', function($scope, $http) {
    var apiHost = 'http://yourdomain.com/wp-json';

    $http.post(apiHost + '/jwt-auth/v1/token', {
      username: 'admin',
      password: 'password'
    })
    .then(function(response) {
      console.log(response.data)
    })
    .catch(function(error) {
      console.error('Error', error.data[0]);
    });
  });
})();

Success Response From The Server

{
  "token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJodHRwOlwvXC9qd3QuZGV2IiwiaWF0IjoxNDM4NTcxMDUwLCJuYmYiOjE0Mzg1NzEwNTAsImV4cCI6MTQzOTE3NTg1MCwiZGF0YSI6eyJ1c2VyIjp7ImlkIjoiMSJ9fX0.YNe6AyWW4B7ZwfFE5wJ0O6qQ8QFcYizimDmBy6hCH_8",
  "user_display_name": "admin",
  "user_email": "[email protected]",
  "user_nicename": "admin"
}

Error Response From The Server

{
  "code": "jwt_auth_failed",
  "data": {
    "status": 403
  },
  "message": "Invalid Credentials."
}

Once you get the token, you must store it somewhere in your application, e.g., in a cookie or using localStorage.

From this point, you should pass this token with every API call.

Sample Call Using The Authorization Header With AngularJS

app.config(function($httpProvider) {
  $httpProvider.interceptors.push(['$q', '$location', '$cookies', function($q, $location, $cookies) {
    return {
      'request': function(config) {
        config.headers = config.headers || {};
        // Assume that you store the token in a cookie
        var globals = $cookies.getObject('globals') || {};
        // If the cookie has the CurrentUser and the token
        // add the Authorization header in each request
        if (globals.currentUser && globals.currentUser.token) {
          config.headers.Authorization = 'Bearer ' + globals.currentUser.token;
        }
        return config;
      }
    };
  }]);
});

The wp-api-jwt-auth plugin will intercept every call to the server and will look for the Authorization Header. If the Authorization header is present, it will try to decode the token and will set the user according to the data stored in it.

If the token is valid, the API call flow will continue as normal.

Sample Headers

POST /resource HTTP/1.1
Host: server.example.com
Authorization: Bearer mF_s9.B5f-4.1JqM

ERRORS

If the token is invalid, an error will be returned. Here are some sample errors:

Invalid Credentials

[
  {
    "code": "jwt_auth_failed",
    "message": "Invalid Credentials.",
    "data": {
      "status": 403
    }
  }
]

Invalid Signature

[
  {
    "code": "jwt_auth_invalid_token",
    "message": "Signature verification failed",
    "data": {
      "status": 403
    }
  }
]

Expired Token

[
  {
    "code": "jwt_auth_invalid_token",
    "message": "Expired token",
    "data": {
      "status": 403
    }
  }
]

Need advanced error tracking? JWT Authentication PRO offers enhanced error tracking and monitoring capabilities.

/wp-json/jwt-auth/v1/token/validate

This is a simple helper endpoint to validate a token. You only need to make a POST request with the Authorization header.

Valid Token Response

{
  "code": "jwt_auth_valid_token",
  "data": {
    "status": 200
  }
}

AVAILABLE HOOKS

The wp-api-jwt-auth plugin is developer-friendly and provides five filters to override the default settings.

jwt_auth_cors_allow_headers

The jwt_auth_cors_allow_headers filter allows you to modify the available headers when CORS support is enabled.

Default Value:

'Access-Control-Allow-Headers, Content-Type, Authorization'

jwt_auth_not_before

The jwt_auth_not_before filter allows you to change the nbf value before the token is created.

Default Value:

Creation time - time()

jwt_auth_expire

The jwt_auth_expire filter allows you to change the exp value before the token is created.

Default Value:

time() + (DAY_IN_SECONDS * 7)

jwt_auth_token_before_sign

The jwt_auth_token_before_sign filter allows you to modify all token data before it is encoded and signed.

Default Value:

$token = array(
    'iss' => get_bloginfo('url'),
    'iat' => $issuedAt,
    'nbf' => $notBefore,
    'exp' => $expire,
    'data' => array(
        'user' => array(
            'id' => $user->data->ID,
        )
    )
);

Want easier customization? JWT Authentication PRO allows you to add custom claims directly through the admin UI.

jwt_auth_token_before_dispatch

The jwt_auth_token_before_dispatch filter allows you to modify the response array before it is sent to the client.

Default Value:

$data = array(
    'token' => $token,
    'user_email' => $user->data->user_email,
    'user_nicename' => $user->data->user_nicename,
    'user_display_name' => $user->data->display_name,
);

jwt_auth_algorithm

The jwt_auth_algorithm filter allows you to modify the signing algorithm.

Default value:

$token = JWT::encode(
    apply_filters('jwt_auth_token_before_sign', $token, $user),
    $secret_key,
    apply_filters('jwt_auth_algorithm', 'HS256')
);

// ...

$token = JWT::decode(
    $token,
    new Key($secret_key, apply_filters('jwt_auth_algorithm', 'HS256'))
);

Testing

I’ve created a small app to test the basic functionality of the plugin. You can get the app and read all the details in the JWT-Client Repo.