Some Oauth

oauth.php

<?php

class Google_OAuth {
    var $client_id;
    var $client_secret;
    
    var $redirect_uri;
    
    var $scopes = array(
        'userinfo' => array(
            'scope' => 'https://www.googleapis.com/auth/userinfo.profile https://www.googleapis.com/auth/userinfo.email',
            'endpoint' => 'https://www.googleapis.com/oauth2/v2/userinfo',
        )
    );
    var $scope = 'userinfo';
    
    var $auth_url = 'https://accounts.google.com/o/oauth2/auth';
    var $token_url = 'https://accounts.google.com/o/oauth2/token';
    
    function __construct ($client_id='', $client_secret='', $redirect_uri='', $scope='') {
        $this->client_id = $client_id;
        $this->client_secret = $client_secret;
        $this->redirect_uri = $redirect_uri;
        $this->scope = $scope;
    }
    
    function request ($url='',$type='GET',$data=NULL,$headers=array()) {
        $type = $type == 'POST' ? 'POST' : 'GET';
        $ch = curl_init($url);
        
        curl_setopt_array($ch,array(
            CURLOPT_MAXREDIRS => 0,
            CURLOPT_HEADER => TRUE,
            CURLOPT_RETURNTRANSFER => TRUE,
            CURLINFO_HEADER_OUT => TRUE,
        ));
        
        if ($type == 'POST') {
            curl_setopt_array($ch,array(
                CURLOPT_POST => TRUE,
                CURLOPT_POSTFIELDS => is_array($data) ? http_build_query($data) : ''
            ));
        }
        else if (is_array($data) && count($data)) {
            $url .= '?' . http_build_query($data);
        }
        
        curl_setopt_array($ch,array(
            CURLOPT_URL => $url,
            CURLOPT_HTTPHEADER => $headers
        ));
        
        $response = curl_exec($ch);
        $headers_sent = curl_getinfo($ch,CURLINFO_HEADER_OUT);
        curl_close($ch);
        
        if (!strlen($response)) {
            $response = '{error:"Empty response from server"}';
            $headers = 'Empty';
        }
        else {
            list($headers,$response) = explode("\r\n\r\n",$response,2);
            
            if (!strlen($response)) {
                $response = '{error:"Empty response from server"}';
            }
        }
        
        $return = json_decode($response);
        $return->request_headers = $headers_sent;
        $return->response_headers = $headers;
        $return->original_response = $response;
        
        return $return;
    }
    
    function request_access_code () {
        $fields = array(
            'response_type' => 'code',
            'scope' => $this->scopes[$this->scope]['scope'],
            'client_id' => $this->client_id,
            'redirect_uri' => $this->redirect_uri,
            'access_type' => 'online' //'offline'
        );
        
        $url = $this->auth_url . '?' . http_build_query($fields);
        header('Location: ' . $url);
         
        return htmlspecialchars($url);
    }
    
    function request_access_token ($code) {
        $fields = array(
            'code' => $code,
            'client_id' => $this->client_id,
            'client_secret' => $this->client_secret,
            'redirect_uri' => $this->redirect_uri,
            'scope' => '',//$this->scopes[$this->scope],
            'grant_type' => 'authorization_code'
        );
        
        $return = $this->request($this->token_url,'POST',$fields);
        $return->method = 'request_access_token';
        
        return $return;
    }
    
    function request_scope ($token) {
        $return = $this->request($this->scopes[$this->scope]['endpoint'],'GET',NULL,array('Authorization: OAuth ' . urlencode($token)));
        $return->method = 'request_scope';
        
        return $return;
    }
    
    function consume_code ($code) {
        $response = $this->request_access_token($code);
        
        if (isset($response->access_token)) {
            return $this->request_scope($response->access_token);
        }
        
        return $response;
    }
}