README

This package provides Google OAuth 2.0 support for the PHP AwUniversity's OAuth 2.0 Client.

This package is compliant with PSR-1, PSR-2 and PSR-4. If you notice compliance oversights, please send a patch via pull request.

Requirements

The following versions of PHP are supported.

PHP 7.0
PHP 7.1
PHP 7.2
PHP 7.3

This package uses OpenID Connect to authenticate users with Google accounts.

To use this package, it will be necessary to have a Google client ID and client secret. These are referred to as {aw-client-id} and {aw-client-secret} in the documentation.

Please follow the Google instructions to create the required credentials.

Installation

To install, use composer:

composer require awuniversity/oauth2-aw

Usage

Authorization Code Flow

use AwU\OAuth2\Client\Provider\Google;

$provider = new Google([
    'clientId'     => '{aw-client-id}',
    'clientSecret' => '{aw-client-secret}',
    'redirectUri'  => 'https://example.com/callback-url',
    'hostedDomain' => 'example.com', // optional; used to restrict access to users on your G Suite/Google Apps for Business accounts
]);

if (!empty($_GET['error'])) {

    // Got an error, probably user denied access
    exit('Got error: ' . htmlspecialchars($_GET['error'], ENT_QUOTES, 'UTF-8'));

} elseif (empty($_GET['code'])) {

    // If we don't have an authorization code then get one
    $authUrl = $provider->getAuthorizationUrl();
    $_SESSION['oauth2state'] = $provider->getState();
    header('Location: ' . $authUrl);
    exit;

} elseif (empty($_GET['state']) || ($_GET['state'] !== $_SESSION['oauth2state'])) {

    // State is invalid, possible CSRF attack in progress
    unset($_SESSION['oauth2state']);
    exit('Invalid state');

} else {

    // Try to get an access token (using the authorization code grant)
    $token = $provider->getAccessToken('authorization_code', [
        'code' => $_GET['code']
    ]);

    // Optional: Now you have a token you can look up a users profile data
    try {

        // We got an access token, let's now get the owner details
        $ownerDetails = $provider->getResourceOwner($token);

        // Use these details to create a new profile
        printf('Hello %s!', $ownerDetails->getFirstName());

    } catch (Exception $e) {

        // Failed to get user details
        exit('Something went wrong: ' . $e->getMessage());

    }

    // Use this to interact with an API on the users behalf
    echo $token->getToken();

    // Use this to get a new access token if the old one expires
    echo $token->getRefreshToken();

    // Unix timestamp at which the access token expires
    echo $token->getExpires();
}

Available Options

The Google provider has the following options:

accessType to use online or offline access
hostedDomain to authenticate G Suite users
prompt to modify the prompt that the user will see
scopes to request access to additional user information

Accessing Token JWT

Google provides a JSON Web Token (JWT) with all access tokens. This token contains basic information about the authenticated user. The JWT can be accessed from the id_token value of the access token:

/** @var AwU\OAuth2\Client\Token\AccessToken $token */
$values = $token->getValues();

/** @var string */
$jwt = $values['id_token'];

Parsing the JWT will require a JWT parser. Refer to parser documentation for instructions.

Refreshing a Token

Refresh tokens are only provided to applications which request offline access. You can specify offline access by setting the accessType option in your provider:

use AwU\OAuth2\Client\Provider\Google;

$provider = new Google([
    'clientId'     => '{aw-client-id}',
    'clientSecret' => '{aw-client-secret}',
    'redirectUri'  => 'https://example.com/callback-url',
    'accessType'   => 'offline',
]);

It is important to note that the refresh token is only returned on the first request after this it will be null. You should securely store the refresh token when it is returned:

$token = $provider->getAccessToken('authorization_code', [
    'code' => $code
]);

// persist the token in a database
$refreshToken = $token->getRefreshToken();

If you ever need to get a new refresh token you can request one by forcing the approval prompt:

$authUrl = $provider->getAuthorizationUrl(['approval_prompt' => 'force']);

Now you have everything you need to refresh an access token using a refresh token:

use AwU\OAuth2\Client\Provider\Google;
use AwU\OAuth2\Client\Grant\RefreshToken;

$provider = new Google([
    'clientId'     => '{aw-client-id}',
    'clientSecret' => '{aw-client-secret}',
    'redirectUri'  => 'https://example.com/callback-url',
]);

$grant = new RefreshToken();
$token = $provider->getAccessToken($grant, ['refresh_token' => $refreshToken]);

Scopes

Additional scopes can be set by using the scope parameter when generating the authorization URL:

$authorizationUrl = $provider->getAuthorizationUrl([
    'scope' => [
        'scope-url-here'
    ],
]);

Testing

Tests can be run with:

composer test

Style checks can be run with:

composer check

awuniversity / oauth2-aw

Maintainers

Details