diff --git a/plugins/login-oauth2/OAuth2/Client.php b/plugins/login-oauth2/OAuth2/Client.php
new file mode 100644
index 000000000..46f34c42f
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/Client.php
@@ -0,0 +1,526 @@
+<?php
+/**
+ * Note : Code is released under the GNU LGPL
+ *
+ * Please do not change the header of this file
+ *
+ * This library is free software; you can redistribute it and/or modify it under the terms of the GNU
+ * Lesser General Public License as published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * See the GNU Lesser General Public License for more details.
+ */
+
+/**
+ * Light PHP wrapper for the OAuth 2.0 protocol.
+ *
+ * This client is based on the OAuth2 specification draft v2.15
+ * http://tools.ietf.org/html/draft-ietf-oauth-v2-15
+ *
+ * @author      Pierrick Charron <pierrick@webstart.fr>
+ * @author      Anis Berejeb <anis.berejeb@gmail.com>
+ * @version     1.3.1-dev
+ */
+namespace OAuth2;
+
+class Client
+{
+    /**
+     * Different AUTH method
+     */
+    const AUTH_TYPE_URI                 = 0;
+    const AUTH_TYPE_AUTHORIZATION_BASIC = 1;
+    const AUTH_TYPE_FORM                = 2;
+
+    /**
+     * Different Access token type
+     */
+    const ACCESS_TOKEN_URI      = 0;
+    const ACCESS_TOKEN_BEARER   = 1;
+    const ACCESS_TOKEN_OAUTH    = 2;
+    const ACCESS_TOKEN_MAC      = 3;
+
+    /**
+    * Different Grant types
+    */
+    const GRANT_TYPE_AUTH_CODE          = 'authorization_code';
+    const GRANT_TYPE_PASSWORD           = 'password';
+    const GRANT_TYPE_CLIENT_CREDENTIALS = 'client_credentials';
+    const GRANT_TYPE_REFRESH_TOKEN      = 'refresh_token';
+
+    /**
+     * HTTP Methods
+     */
+    const HTTP_METHOD_GET    = 'GET';
+    const HTTP_METHOD_POST   = 'POST';
+    const HTTP_METHOD_PUT    = 'PUT';
+    const HTTP_METHOD_DELETE = 'DELETE';
+    const HTTP_METHOD_HEAD   = 'HEAD';
+    const HTTP_METHOD_PATCH   = 'PATCH';
+
+    /**
+     * HTTP Form content types
+     */
+    const HTTP_FORM_CONTENT_TYPE_APPLICATION = 0;
+    const HTTP_FORM_CONTENT_TYPE_MULTIPART = 1;
+
+    /**
+     * Client ID
+     *
+     * @var string
+     */
+    protected $client_id = null;
+
+    /**
+     * Client Secret
+     *
+     * @var string
+     */
+    protected $client_secret = null;
+
+    /**
+     * Client Authentication method
+     *
+     * @var int
+     */
+    protected $client_auth = self::AUTH_TYPE_URI;
+
+    /**
+     * Access Token
+     *
+     * @var string
+     */
+    protected $access_token = null;
+
+    /**
+     * Access Token Type
+     *
+     * @var int
+     */
+    protected $access_token_type = self::ACCESS_TOKEN_URI;
+
+    /**
+     * Access Token Secret
+     *
+     * @var string
+     */
+    protected $access_token_secret = null;
+
+    /**
+     * Access Token crypt algorithm
+     *
+     * @var string
+     */
+    protected $access_token_algorithm = null;
+
+    /**
+     * Access Token Parameter name
+     *
+     * @var string
+     */
+    protected $access_token_param_name = 'access_token';
+
+    /**
+     * The path to the certificate file to use for https connections
+     *
+     * @var string  Defaults to .
+     */
+    protected $certificate_file = null;
+
+    /**
+     * cURL options
+     *
+     * @var array
+     */
+    protected $curl_options = array();
+
+    /**
+     * Construct
+     *
+     * @param string $client_id Client ID
+     * @param string $client_secret Client Secret
+     * @param int    $client_auth (AUTH_TYPE_URI, AUTH_TYPE_AUTHORIZATION_BASIC, AUTH_TYPE_FORM)
+     * @param string $certificate_file Indicates if we want to use a certificate file to trust the server. Optional, defaults to null.
+     * @return void
+     */
+    public function __construct($client_id, $client_secret, $client_auth = self::AUTH_TYPE_URI, $certificate_file = null)
+    {
+        if (!extension_loaded('curl')) {
+            throw new Exception('The PHP exention curl must be installed to use this library.', Exception::CURL_NOT_FOUND);
+        }
+
+        $this->client_id     = $client_id;
+        $this->client_secret = $client_secret;
+        $this->client_auth   = $client_auth;
+        $this->certificate_file = $certificate_file;
+        if (!empty($this->certificate_file)  && !is_file($this->certificate_file)) {
+            throw new InvalidArgumentException('The certificate file was not found', InvalidArgumentException::CERTIFICATE_NOT_FOUND);
+        }
+    }
+
+    /**
+     * Get the client Id
+     *
+     * @return string Client ID
+     */
+    public function getClientId()
+    {
+        return $this->client_id;
+    }
+
+    /**
+     * Get the client Secret
+     *
+     * @return string Client Secret
+     */
+    public function getClientSecret()
+    {
+        return $this->client_secret;
+    }
+
+    /**
+     * getAuthenticationUrl
+     *
+     * @param string $auth_endpoint Url of the authentication endpoint
+     * @param string $redirect_uri  Redirection URI
+     * @param array  $extra_parameters  Array of extra parameters like scope or state (Ex: array('scope' => null, 'state' => ''))
+     * @return string URL used for authentication
+     */
+    public function getAuthenticationUrl($auth_endpoint, $redirect_uri, array $extra_parameters = array())
+    {
+        $parameters = array_merge(array(
+            'response_type' => 'code',
+            'client_id'     => $this->client_id,
+            'redirect_uri'  => $redirect_uri
+        ), $extra_parameters);
+        return $auth_endpoint . '?' . http_build_query($parameters, '', '&');
+    }
+
+    /**
+     * getAccessToken
+     *
+     * @param string $token_endpoint    Url of the token endpoint
+     * @param string $grant_type        Grant Type ('authorization_code', 'password', 'client_credentials', 'refresh_token', or a custom code (@see GrantType Classes)
+     * @param array  $parameters        Array sent to the server (depend on which grant type you're using)
+     * @param array  $extra_headers     Array of extra headers
+     * @return array Array of parameters required by the grant_type (CF SPEC)
+     */
+    public function getAccessToken($token_endpoint, $grant_type, array $parameters, array $extra_headers = array())
+    {
+        if (!$grant_type) {
+            throw new InvalidArgumentException('The grant_type is mandatory.', InvalidArgumentException::INVALID_GRANT_TYPE);
+        }
+        $grantTypeClassName = $this->convertToCamelCase($grant_type);
+        $grantTypeClass =  __NAMESPACE__ . '\\GrantType\\' . $grantTypeClassName;
+        if (!class_exists($grantTypeClass)) {
+            throw new InvalidArgumentException('Unknown grant type \'' . $grant_type . '\'', InvalidArgumentException::INVALID_GRANT_TYPE);
+        }
+        $grantTypeObject = new $grantTypeClass();
+        $grantTypeObject->validateParameters($parameters);
+        if (!defined($grantTypeClass . '::GRANT_TYPE')) {
+            throw new Exception('Unknown constant GRANT_TYPE for class ' . $grantTypeClassName, Exception::GRANT_TYPE_ERROR);
+        }
+        $parameters['grant_type'] = $grantTypeClass::GRANT_TYPE;
+        $http_headers = $extra_headers;
+        switch ($this->client_auth) {
+            case self::AUTH_TYPE_URI:
+            case self::AUTH_TYPE_FORM:
+                $parameters['client_id'] = $this->client_id;
+                $parameters['client_secret'] = $this->client_secret;
+                break;
+            case self::AUTH_TYPE_AUTHORIZATION_BASIC:
+                $parameters['client_id'] = $this->client_id;
+                $http_headers['Authorization'] = 'Basic ' . base64_encode($this->client_id .  ':' . $this->client_secret);
+                break;
+            default:
+                throw new Exception('Unknown client auth type.', Exception::INVALID_CLIENT_AUTHENTICATION_TYPE);
+                break;
+        }
+
+        return $this->executeRequest($token_endpoint, $parameters, self::HTTP_METHOD_POST, $http_headers, self::HTTP_FORM_CONTENT_TYPE_APPLICATION);
+    }
+
+    /**
+     * setToken
+     *
+     * @param string $token Set the access token
+     * @return void
+     */
+    public function setAccessToken($token)
+    {
+        $this->access_token = $token;
+    }
+
+    /**
+     * Check if there is an access token present
+     *
+     * @return bool Whether the access token is present
+     */
+    public function hasAccessToken()
+    {
+        return !!$this->access_token;
+    }
+
+    /**
+     * Set the client authentication type
+     *
+     * @param string $client_auth (AUTH_TYPE_URI, AUTH_TYPE_AUTHORIZATION_BASIC, AUTH_TYPE_FORM)
+     * @return void
+     */
+    public function setClientAuthType($client_auth)
+    {
+        $this->client_auth = $client_auth;
+    }
+
+    /**
+     * Set an option for the curl transfer
+     *
+     * @param int   $option The CURLOPT_XXX option to set
+     * @param mixed $value  The value to be set on option
+     * @return void
+     */
+    public function setCurlOption($option, $value)
+    {
+        $this->curl_options[$option] = $value;
+    }
+
+    /**
+     * Set multiple options for a cURL transfer
+     *
+     * @param array $options An array specifying which options to set and their values
+     * @return void
+     */
+    public function setCurlOptions($options)
+    {
+        $this->curl_options = array_merge($this->curl_options, $options);
+    }
+
+    /**
+     * Set the access token type
+     *
+     * @param int $type Access token type (ACCESS_TOKEN_BEARER, ACCESS_TOKEN_MAC, ACCESS_TOKEN_URI)
+     * @param string $secret The secret key used to encrypt the MAC header
+     * @param string $algorithm Algorithm used to encrypt the signature
+     * @return void
+     */
+    public function setAccessTokenType($type, $secret = null, $algorithm = null)
+    {
+        $this->access_token_type = $type;
+        $this->access_token_secret = $secret;
+        $this->access_token_algorithm = $algorithm;
+    }
+
+    /**
+     * Fetch a protected ressource
+     *
+     * @param string $protected_ressource_url Protected resource URL
+     * @param array  $parameters Array of parameters
+     * @param string $http_method HTTP Method to use (POST, PUT, GET, HEAD, DELETE)
+     * @param array  $http_headers HTTP headers
+     * @param int    $form_content_type HTTP form content type to use
+     * @return array
+     */
+    public function fetch($protected_resource_url, $parameters = array(), $http_method = self::HTTP_METHOD_GET, array $http_headers = array(), $form_content_type = self::HTTP_FORM_CONTENT_TYPE_MULTIPART)
+    {
+        if ($this->access_token) {
+            switch ($this->access_token_type) {
+                case self::ACCESS_TOKEN_URI:
+                    if (is_array($parameters)) {
+                        $parameters[$this->access_token_param_name] = $this->access_token;
+                    } else {
+                        throw new InvalidArgumentException(
+                            'You need to give parameters as array if you want to give the token within the URI.',
+                            InvalidArgumentException::REQUIRE_PARAMS_AS_ARRAY
+                        );
+                    }
+                    break;
+                case self::ACCESS_TOKEN_BEARER:
+                    $http_headers['Authorization'] = 'Bearer ' . $this->access_token;
+                    break;
+                case self::ACCESS_TOKEN_OAUTH:
+                    $http_headers['Authorization'] = 'OAuth ' . $this->access_token;
+                    break;
+                case self::ACCESS_TOKEN_MAC:
+                    $http_headers['Authorization'] = 'MAC ' . $this->generateMACSignature($protected_resource_url, $parameters, $http_method);
+                    break;
+                default:
+                    throw new Exception('Unknown access token type.', Exception::INVALID_ACCESS_TOKEN_TYPE);
+                    break;
+            }
+        }
+        return $this->executeRequest($protected_resource_url, $parameters, $http_method, $http_headers, $form_content_type);
+    }
+
+    /**
+     * Generate the MAC signature
+     *
+     * @param string $url Called URL
+     * @param array  $parameters Parameters
+     * @param string $http_method Http Method
+     * @return string
+     */
+    private function generateMACSignature($url, $parameters, $http_method)
+    {
+        $timestamp = time();
+        $nonce = uniqid();
+        $parsed_url = parse_url($url);
+        if (!isset($parsed_url['port']))
+        {
+            $parsed_url['port'] = ($parsed_url['scheme'] == 'https') ? 443 : 80;
+        }
+        if ($http_method == self::HTTP_METHOD_GET) {
+            if (is_array($parameters)) {
+                $parsed_url['path'] .= '?' . http_build_query($parameters, '', '&');
+            } elseif ($parameters) {
+                $parsed_url['path'] .= '?' . $parameters;
+            }
+        }
+
+        $signature = base64_encode(hash_hmac($this->access_token_algorithm,
+                    $timestamp . "\n"
+                    . $nonce . "\n"
+                    . $http_method . "\n"
+                    . $parsed_url['path'] . "\n"
+                    . $parsed_url['host'] . "\n"
+                    . $parsed_url['port'] . "\n\n"
+                    , $this->access_token_secret, true));
+
+        return 'id="' . $this->access_token . '", ts="' . $timestamp . '", nonce="' . $nonce . '", mac="' . $signature . '"';
+    }
+
+    /**
+     * Execute a request (with curl)
+     *
+     * @param string $url URL
+     * @param mixed  $parameters Array of parameters
+     * @param string $http_method HTTP Method
+     * @param array  $http_headers HTTP Headers
+     * @param int    $form_content_type HTTP form content type to use
+     * @return array
+     */
+    private function executeRequest($url, $parameters = array(), $http_method = self::HTTP_METHOD_GET, array $http_headers = null, $form_content_type = self::HTTP_FORM_CONTENT_TYPE_MULTIPART)
+    {
+        $curl_options = array(
+            CURLOPT_RETURNTRANSFER => true,
+            CURLOPT_SSL_VERIFYPEER => true,
+            CURLOPT_CUSTOMREQUEST  => $http_method
+        );
+
+        switch($http_method) {
+            case self::HTTP_METHOD_POST:
+                $curl_options[CURLOPT_POST] = true;
+                /* No break */
+            case self::HTTP_METHOD_PUT:
+			case self::HTTP_METHOD_PATCH:
+
+                /**
+                 * Passing an array to CURLOPT_POSTFIELDS will encode the data as multipart/form-data,
+                 * while passing a URL-encoded string will encode the data as application/x-www-form-urlencoded.
+                 * http://php.net/manual/en/function.curl-setopt.php
+                 */
+                if(is_array($parameters) && self::HTTP_FORM_CONTENT_TYPE_APPLICATION === $form_content_type) {
+                    $parameters = http_build_query($parameters, '', '&');
+                }
+                $curl_options[CURLOPT_POSTFIELDS] = $parameters;
+                break;
+            case self::HTTP_METHOD_HEAD:
+                $curl_options[CURLOPT_NOBODY] = true;
+                /* No break */
+            case self::HTTP_METHOD_DELETE:
+            case self::HTTP_METHOD_GET:
+                if (is_array($parameters) && count($parameters) > 0) {
+                    $url .= '?' . http_build_query($parameters, '', '&');
+                } elseif ($parameters) {
+                    $url .= '?' . $parameters;
+                }
+                break;
+            default:
+                break;
+        }
+
+        $curl_options[CURLOPT_URL] = $url;
+
+        if (is_array($http_headers)) {
+            $header = array();
+            foreach($http_headers as $key => $parsed_urlvalue) {
+                $header[] = "$key: $parsed_urlvalue";
+            }
+            $curl_options[CURLOPT_HTTPHEADER] = $header;
+        }
+
+        $ch = curl_init();
+        curl_setopt_array($ch, $curl_options);
+        // https handling
+        if (!empty($this->certificate_file)) {
+            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, true);
+            curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
+            curl_setopt($ch, CURLOPT_CAINFO, $this->certificate_file);
+        } else {
+            // bypass ssl verification
+            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
+            curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
+        }
+        if (!empty($this->curl_options)) {
+            curl_setopt_array($ch, $this->curl_options);
+        }
+        $result = curl_exec($ch);
+        $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
+        $content_type = curl_getinfo($ch, CURLINFO_CONTENT_TYPE);
+        if ($curl_error = curl_error($ch)) {
+            throw new Exception($curl_error, Exception::CURL_ERROR);
+        } else {
+            $json_decode = json_decode($result, true);
+        }
+        curl_close($ch);
+
+        return array(
+            'result' => (null === $json_decode) ? $result : $json_decode,
+            'code' => $http_code,
+            'content_type' => $content_type
+        );
+    }
+
+    /**
+     * Set the name of the parameter that carry the access token
+     *
+     * @param string $name Token parameter name
+     * @return void
+     */
+    public function setAccessTokenParamName($name)
+    {
+        $this->access_token_param_name = $name;
+    }
+
+    /**
+     * Converts the class name to camel case
+     *
+     * @param  mixed  $grant_type  the grant type
+     * @return string
+     */
+    private function convertToCamelCase($grant_type)
+    {
+        $parts = explode('_', $grant_type);
+        array_walk($parts, function(&$item) { $item = ucfirst($item);});
+        return implode('', $parts);
+    }
+}
+
+class Exception extends \Exception
+{
+    const CURL_NOT_FOUND                     = 0x01;
+    const CURL_ERROR                         = 0x02;
+    const GRANT_TYPE_ERROR                   = 0x03;
+    const INVALID_CLIENT_AUTHENTICATION_TYPE = 0x04;
+    const INVALID_ACCESS_TOKEN_TYPE          = 0x05;
+}
+
+class InvalidArgumentException extends \InvalidArgumentException
+{
+    const INVALID_GRANT_TYPE      = 0x01;
+    const CERTIFICATE_NOT_FOUND   = 0x02;
+    const REQUIRE_PARAMS_AS_ARRAY = 0x03;
+    const MISSING_PARAMETER       = 0x04;
+}
diff --git a/plugins/login-oauth2/OAuth2/GrantType/AuthorizationCode.php b/plugins/login-oauth2/OAuth2/GrantType/AuthorizationCode.php
new file mode 100644
index 000000000..f3436e4c5
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/GrantType/AuthorizationCode.php
@@ -0,0 +1,41 @@
+<?php
+namespace OAuth2\GrantType;
+
+use OAuth2\InvalidArgumentException;
+
+/**
+ * Authorization code  Grant Type Validator
+ */
+class AuthorizationCode implements IGrantType
+{
+    /**
+     * Defines the Grant Type
+     *
+     * @var string  Defaults to 'authorization_code'.
+     */
+    const GRANT_TYPE = 'authorization_code';
+
+    /**
+     * Adds a specific Handling of the parameters
+     *
+     * @return array of Specific parameters to be sent.
+     * @param  mixed  $parameters the parameters array (passed by reference)
+     */
+    public function validateParameters(&$parameters)
+    {
+        if (!isset($parameters['code']))
+        {
+            throw new InvalidArgumentException(
+                'The \'code\' parameter must be defined for the Authorization Code grant type',
+                InvalidArgumentException::MISSING_PARAMETER
+            );
+        }
+        elseif (!isset($parameters['redirect_uri']))
+        {
+            throw new InvalidArgumentException(
+                'The \'redirect_uri\' parameter must be defined for the Authorization Code grant type',
+                InvalidArgumentException::MISSING_PARAMETER
+            );
+        }
+    }
+}
diff --git a/plugins/login-oauth2/OAuth2/GrantType/ClientCredentials.php b/plugins/login-oauth2/OAuth2/GrantType/ClientCredentials.php
new file mode 100644
index 000000000..c6c81f84b
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/GrantType/ClientCredentials.php
@@ -0,0 +1,25 @@
+<?php
+namespace OAuth2\GrantType;
+
+/**
+ * Client Credentials Parameters 
+ */
+class ClientCredentials implements IGrantType
+{
+    /**
+     * Defines the Grant Type
+     * 
+     * @var string  Defaults to 'client_credentials'. 
+     */
+    const GRANT_TYPE = 'client_credentials';
+
+    /**
+     * Adds a specific Handling of the parameters
+     * 
+     * @return array of Specific parameters to be sent.
+     * @param  mixed  $parameters the parameters array (passed by reference)
+     */
+    public function validateParameters(&$parameters)
+    {
+    }
+}
diff --git a/plugins/login-oauth2/OAuth2/GrantType/IGrantType.php b/plugins/login-oauth2/OAuth2/GrantType/IGrantType.php
new file mode 100644
index 000000000..60631922f
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/GrantType/IGrantType.php
@@ -0,0 +1,15 @@
+<?php
+namespace OAuth2\GrantType;
+/**
+ * Specific GrantType Interface
+ */
+interface IGrantType 
+{
+    /**
+     * Adds a specific Handling of the parameters
+     * 
+     * @return array of Specific parameters to be sent.
+     * @param  mixed  $parameters the parameters array (passed by reference)
+     */
+    public function validateParameters(&$parameters);
+}
diff --git a/plugins/login-oauth2/OAuth2/GrantType/Password.php b/plugins/login-oauth2/OAuth2/GrantType/Password.php
new file mode 100644
index 000000000..8972409c9
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/GrantType/Password.php
@@ -0,0 +1,41 @@
+<?php
+namespace OAuth2\GrantType;
+
+use OAuth2\InvalidArgumentException;
+
+/**
+ * Password Parameters
+ */
+class Password implements IGrantType
+{
+    /**
+     * Defines the Grant Type
+     *
+     * @var string  Defaults to 'password'.
+     */
+    const GRANT_TYPE = 'password';
+
+    /**
+     * Adds a specific Handling of the parameters
+     *
+     * @return array of Specific parameters to be sent.
+     * @param  mixed  $parameters the parameters array (passed by reference)
+     */
+    public function validateParameters(&$parameters)
+    {
+        if (!isset($parameters['username']))
+        {
+            throw new InvalidArgumentException(
+                'The \'username\' parameter must be defined for the Password grant type',
+                InvalidArgumentException::MISSING_PARAMETER
+            );
+        }
+        elseif (!isset($parameters['password']))
+        {
+            throw new InvalidArgumentException(
+                'The \'password\' parameter must be defined for the Password grant type',
+                InvalidArgumentException::MISSING_PARAMETER
+            );
+        }
+    }
+}
diff --git a/plugins/login-oauth2/OAuth2/GrantType/RefreshToken.php b/plugins/login-oauth2/OAuth2/GrantType/RefreshToken.php
new file mode 100644
index 000000000..12fccb04e
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/GrantType/RefreshToken.php
@@ -0,0 +1,34 @@
+<?php
+namespace OAuth2\GrantType;
+
+use OAuth2\InvalidArgumentException;
+
+/**
+ * Refresh Token  Parameters
+ */
+class RefreshToken implements IGrantType
+{
+    /**
+     * Defines the Grant Type
+     *
+     * @var string  Defaults to 'refresh_token'.
+     */
+    const GRANT_TYPE = 'refresh_token';
+
+    /**
+     * Adds a specific Handling of the parameters
+     *
+     * @return array of Specific parameters to be sent.
+     * @param  mixed  $parameters the parameters array (passed by reference)
+     */
+    public function validateParameters(&$parameters)
+    {
+        if (!isset($parameters['refresh_token']))
+        {
+            throw new InvalidArgumentException(
+                'The \'refresh_token\' parameter must be defined for the refresh token grant type',
+                InvalidArgumentException::MISSING_PARAMETER
+            );
+        }
+    }
+}
diff --git a/plugins/login-oauth2/OAuth2/LICENSE b/plugins/login-oauth2/OAuth2/LICENSE
new file mode 100644
index 000000000..8000a6faa
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/LICENSE
@@ -0,0 +1,504 @@
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
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diff --git a/plugins/login-oauth2/OAuth2/README.md b/plugins/login-oauth2/OAuth2/README.md
new file mode 100644
index 000000000..9de3570e0
--- /dev/null
+++ b/plugins/login-oauth2/OAuth2/README.md
@@ -0,0 +1,105 @@
+# Light PHP wrapper for the OAuth 2.0
+
+[![Latest Stable Version](https://poser.pugx.org/adoy/fastcgi-client/v/stable)](https://packagist.org/packages/adoy/fastcgi-client)
+[![GitHub](https://img.shields.io/github/license/adoy/PHP-OAuth2)](LICENSE)
+[![Total Downloads](https://poser.pugx.org/adoy/fastcgi-client/downloads)](https://packagist.org/packages/adoy/fastcgi-client)
+
+
+## How can I use it ?
+
+```php
+<?php
+
+require('Client.php');
+require('GrantType/IGrantType.php');
+require('GrantType/AuthorizationCode.php');
+
+const CLIENT_ID     = 'your client id';
+const CLIENT_SECRET = 'your client secret';
+
+const REDIRECT_URI           = 'http://url/of/this.php';
+const AUTHORIZATION_ENDPOINT = 'https://graph.facebook.com/oauth/authorize';
+const TOKEN_ENDPOINT         = 'https://graph.facebook.com/oauth/access_token';
+
+$client = new OAuth2\Client(CLIENT_ID, CLIENT_SECRET);
+if (!isset($_GET['code']))
+{
+    $auth_url = $client->getAuthenticationUrl(AUTHORIZATION_ENDPOINT, REDIRECT_URI);
+    header('Location: ' . $auth_url);
+    die('Redirect');
+}
+else
+{
+    $params = array('code' => $_GET['code'], 'redirect_uri' => REDIRECT_URI);
+    $response = $client->getAccessToken(TOKEN_ENDPOINT, 'authorization_code', $params);
+    parse_str($response['result'], $info);
+    $client->setAccessToken($info['access_token']);
+    $response = $client->fetch('https://graph.facebook.com/me');
+    var_dump($response, $response['result']);
+}
+```
+
+## How can I add a new Grant Type ?
+
+Simply write a new class in the namespace OAuth2\GrantType. You can place the class file under GrantType.
+Here is an example :
+
+```php
+<?php
+
+namespace OAuth2\GrantType;
+
+/**
+ * MyCustomGrantType Grant Type
+ */
+class MyCustomGrantType implements IGrantType
+{
+    /**
+     * Defines the Grant Type
+     *
+     * @var string  Defaults to 'my_custom_grant_type'.
+     */
+    const GRANT_TYPE = 'my_custom_grant_type';
+
+    /**
+     * Adds a specific Handling of the parameters
+     *
+     * @return array of Specific parameters to be sent.
+     * @param  mixed  $parameters the parameters array (passed by reference)
+     */
+    public function validateParameters(&$parameters)
+    {
+        if (!isset($parameters['first_mandatory_parameter']))
+        {
+            throw new \Exception('The \'first_mandatory_parameter\' parameter must be defined for the Password grant type');
+        }
+        elseif (!isset($parameters['second_mandatory_parameter']))
+        {
+            throw new \Exception('The \'seconde_mandatory_parameter\' parameter must be defined for the Password grant type');
+        }
+    }
+}
+```
+
+call the OAuth client getAccessToken with the grantType you defined in the GRANT_TYPE constant, As following :
+
+```
+$response = $client->getAccessToken(TOKEN_ENDPOINT, 'my_custom_grant_type', $params);
+```
+
+## LICENSE
+
+This Code is released under the GNU LGPL
+
+Please do not change the header of the file(s).
+
+This library is free software; you can redistribute it and/or modify it
+under the terms of the GNU Lesser General Public License as published
+by the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.
+
+See the GNU Lesser General Public License for more details.
diff --git a/plugins/login-oauth2/index.php b/plugins/login-oauth2/index.php
index 1a8027077..7787ae23b 100644
--- a/plugins/login-oauth2/index.php
+++ b/plugins/login-oauth2/index.php
@@ -32,6 +32,12 @@ class LoginOAuth2Plugin extends \RainLoop\Plugins\AbstractPlugin
 		$this->addHook('sieve.before-login', 'clientLogin');
 //		$this->addHook('sieve.after-login', array($this, $oSieveClient, $oSettings));
 		$this->addHook('filter.account', 'filterAccount');
+
+		spl_autoload_register(function($classname){
+			if (str_starts_with($classname, 'OAuth2\\')) {
+				include_once __DIR__ . strtr("\\{$sClassName}", '\\', DIRECTORY_SEPARATOR) . '.php';
+			}
+		});
 	}
 
 	public function configMapping() : array
@@ -175,10 +181,10 @@ class LoginOAuth2Plugin extends \RainLoop\Plugins\AbstractPlugin
 		$client_id = \trim($this->Config()->Get('plugin', 'client_id', ''));
 		$client_secret = \trim($this->Config()->Get('plugin', 'client_secret', ''));
 		if ($client_id && $client_secret) {
-			include_once APP_VERSION_ROOT_PATH.'app/libraries/PHP-OAuth2/Client.php';
-			include_once APP_VERSION_ROOT_PATH.'app/libraries/PHP-OAuth2/GrantType/IGrantType.php';
-			include_once APP_VERSION_ROOT_PATH.'app/libraries/PHP-OAuth2/GrantType/AuthorizationCode.php';
-			include_once APP_VERSION_ROOT_PATH.'app/libraries/PHP-OAuth2/GrantType/RefreshToken.php';
+//			include_once __DIR__ . '/OAuth2/Client.php';
+//			include_once __DIR__ . '/OAuth2/GrantType/IGrantType.php';
+//			include_once __DIR__ . '/OAuth2/GrantType/AuthorizationCode.php';
+//			include_once __DIR__ . '/OAuth2/GrantType/RefreshToken.php';
 
 			try
 			{