Tracking PHP API Accesses using Google Analytics Part 2: Recording API Accesses - PHP Google Analytics API Metrics Tracker package blog

As for the disadvantages, some of the parameters are possible to defined by using data received from the client calling the API and configuring Google Analytics API for using this. For instance, you can try to analyze the geography of your API users by their IP addresses. You can also try to translate ‘user agent' value of your client.

In order to distinguish different API clients from each other, you need to assign each client a unique identifier that they will pass in the call. This is a ‘partner-id' parameter in the sample below.

<?php
/**
 * Calls Google Analytics to track usage, e.g. of our API
 * done for http://yasno.tv/ project
 * @author Alexander Skakunov <alex.skakunov@gmail.com>
 */
class Yasno_Controller_Plugin_Integration_Google_Analytics_Mobile_Tracker extends Zend_Controller_Plugin_Abstract {
    
    const G_VERSION = '4.4sh';
    const COOKIE_NAME = '__utmmobile';
    const COOKIE_PATH = '/';
    const COOKIE_USER_PERSISTENCE = 63072000; // Two years in seconds.
    const UTM_GIF_LOCATION = 'http://www.google-analytics.com/__utm.gif';
    /**
     * @var Zend_Http_Client
     */
    protected $_httpClient;
    public function __construct() {
        $this->setHttpClient(new Zend_Http_Client);
    }
    /**
     * @return Zend_Http_Client $httpClient
     */
    public function getHttpClient() {
        return $this->_httpClient;
    }
    /**
     * @param Zend_Http_Client
     * @return this
     */
    public function setHttpClient(Zend_Http_Client $httpClient) {
        $this->_httpClient = $httpClient;
        return $this;
    }
    /**
     * form URL with params and call Google backend to send these params
     * @param Zend_Controller_Request_Abstract $request
     */
    public function preDispatch(Zend_Controller_Request_Abstract $request) {
        if (is_null($request->getServer('SERVER_NAME'))) {
            return;
        }
        $config = Zend_Registry::get('config');
        if (empty($config->google->analytics->tracking->code)) {
            return;
        }
        $visitorId = $this->_getVisitorId($request); 
        
        $this->_buildUtmUrl($visitorId, $request);
        $this->_setCookie($visitorId);
        $httpClient = $this->getHttpClient();
        
        if ('' != $request->getServer('HTTP_USER_AGENT')) {
            $httpClient->setConfig(array('useragent', $request->getServer('HTTP_USER_AGENT')));
        }
        if ('' != $request->getServer('HTTP_ACCEPT_LANGUAGE')) {
            $httpClient->setHeaders('Accept-Language: ' . $request->getServer('HTTP_ACCEPT_LANGUAGE'));
        }
        $httpClient->request();
    }
    
    /**
     * sets params of HTTP client to build the URL to call Google backend
     * @param string $visitorId
     */
    protected function _buildUtmUrl($visitorId, $request) {
        $config = Zend_Registry::get('config');
        $trackingCode = $config->google->analytics->tracking->code;
        $trackingCode = 'MO' . substr($trackingCode, 2);
        $client = $this->getHttpClient();
        $client->setMethod(Zend_Http_Client::GET);
        $client->setUri(self::UTM_GIF_LOCATION);
        $client->setParameterGet(
            array(
                'utmwv' => self::G_VERSION,
                'utmn' => rand(0, 0x7fffffff),
                'utmhn' => $request->getServer('SERVER_NAME'),
                'utmr' => $request->getServer('HTTP_REFERER'),
                'utmp' => $request->getServer('REQUEST_URI'),
                'utmac' => $trackingCode,
                'utmcc' => '__utma%3D999.999.999.999.999.1%3B',
                'utmvid' => $visitorId,
                'utmip' => $this->_getIP($request),
           )
       );
    }
    /**
     * The last octect of the IP address is removed to anonymize the user.
     * @param Zend_Controller_Request_Abstract $request
     * @return string
     */
    protected function _getIP($request) {
        $realIp = !is_null($request->getServer('HTTP_X_REAL_IP'))
          ? $request->getServer('HTTP_X_REAL_IP')
          : $request->getServer('REMOTE_ADDR');
        if (empty($realIp)) {
          return '';
        }
        // Capture the first three octects of the IP address and replace the forth
        // with 0, e.g. 124.455.3.123 becomes 124.455.3.0
        $regex = '/^([^.]+\.[^.]+\.[^.]+\.).*/';
        if (preg_match($regex, $realIp, $matches)) {
            return $matches[1] . '0';
        } 
        return '';
    }
    /**
     * set visitor ID by one of 3 rules, required for proper tracking
     * @param Zend_Controller_Request_Abstract $request
     * @return string
     */
    protected function _getVisitorId(Zend_Controller_Request_Abstract $request) {
        // If there is a value in the cookie, don't change it.
        if (!empty($_COOKIE[self::COOKIE_NAME])) {
          return $_COOKIE[self::COOKIE_NAME];
        }
        
        if (null != $request->getParam('partner-id')) {
            return $request->getParam('partner-id');
        }
        return '0x' . substr(md5($request->getServer('HTTP_USER_AGENT') . uniqid(rand(0, 0x7fffffff), true)), 0, 16);
    }
    /**
     * Add visitor ID cookie to the response.
     * @param string $visitorId
     */
    protected function _setCookie($visitorId) {
        $cookie = new Zend_Http_Cookie(
            self::COOKIE_NAME,
            $visitorId,
            $_SERVER['SERVER_NAME'],
            time()+self::COOKIE_USER_PERSISTENCE,
            self::COOKIE_PATH
       );
        $this->getHttpClient()->setCookie($cookie);
    }
}