Build a Visitor Tracking System for your Website with PHP

If you have a website , you are probably interested in knowing details of your visitors like : — physical   location  ,  which webpages they visit , date/time , how did they get to your site , etc — . There are some online tracking options available , like google analytics or  your hosting provider may offer you  some statistics . But what if you want a customized  tracker that shows you only what you need ? Once again , PHP  has build-in variables  that deliver tracking and browser information . Superglobal built-in variable $_SERVER takes certain parameters and will “dump” or deliver tracking information . Some of these variables rely on the server and or browser settings (user-Agent) and may be disabled or customized  , so take it in account when analyzing the data .

The superglobal $_SERVER array has 32 values , you can explore these values by running :

echo “<pre>”;
print_r($_SERVER);
echo “</pre>” ;

My previous article “Logging Visitor’s IP with PHP  ” was a simple example of logging visitor’s location into a “txt” file . This article will present a practical example for a tracker php script that saves the following information about your visitors in a database :   their ip address ,  location (country and city) based on their ip , the date and time of their visit , some information about the browser they used and their operating system , the referer (if they clicked on a link on another site to get to yours , you will know which site referred them)  and the query string they searched for in case they were referred by a search engine . Most of these details are “hosted” in the super-global array  “$_SERVER” , except  country / city information  . We will query a web-service that will translate the IP to country / city .  And last but not least the script will  check if the visitor was a bot (these are software applications that run automated tasks over the Internet like Google’s index bot ) .   We will download a file which has recorded the ID’s of 300 known bot-engines , this list will be used by our script as reference to detect  if the user- agent is a bot .

All this can be achieved in seven simple steps , follow along or download the source code :

Step 1 : Create a table into the database where the details will be stored . The source code for this article contains a visitor_tracker.sql file , just import this file via phpMyadmin or via the command-line into your database .

Step 2 : The translation IP / country-city will be made by a web-service available from ipinfodb.com . This web-service demands an API-key which is free , though you have to make an registration (only a few minutes )  .

Step 3 : Download the  list of known bots .  This plain text file contains details about each bot . We only need the bot- id from this file  , so we have to parse the file and extract only this  information . A function , getBotList() , will load the file and return an array with all bot-id’s .

Step 4 : The function is_bot()  will compare the $_SERVER[‘HTTP_USER_AGENT’]  variable against the bot-list  and return a Boolean value (true/ false) .

Step 5 : Query the web-service with visitor’s IP , it will return a string with information (the response can also be in xml , json ) . We have to parse the string and assign the  values to variables which will be recorded into the database-table . The site of this web-service provide script examples which can be used to query it’s service . I decided to build my own script , it’s only five lines of code , it use PHP’s curl() extension . Most hosts have this extension enabled by default   (run a phpinfo() to verify that it’s enabled)  , so you can use my code . If your host doesn’t support the curl extension , use the class provided by ipinfo.com . My previous article ” Accessing Remote Url’s using Curl ” made a good introduction to this topic , read that article if you like to learn more about the curl extension  .

Step 6 : Parsing the string from the web-service is simple as : converting the string into an array (explode() ) and assigning the values of this array to variables .

Step 7 : Querying and Inserting all values into the database . Finally closing the DB-connection .

Step 7_2 : Paste the code at the end of each web-page . A better option is to store the code into a file outside your public server directory (root-dir)  and include the code with an “include” statement . If you choose the last option , don’t forget to configure PHP’s  include path .

Here follows the complete code : 

<?php

$ip = $_SERVER['REMOTE_ADDR'] ;

/* Set your API key this is a fake example 🙂 */
$api= "1ade0eec6de005cfeedd12678aac3cbf4f47c120bbf83b3cc" ;
$apiurl = "http://api.ipinfodb.com/v3/ip-city/?key=$api&ip=$ip" ;

/* Prepare connection to ipinfodb.com and parse results into variables  */
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "$apiurl");
/**
* Ask cURL to return the contents in a variable
* instead of simply echoing them to the browser.
*/
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
/**
* Execute the cURL session
*/
$contents = curl_exec ($ch);
/**
* Close cURL session
*/
curl_close ($ch);
/*Parse the returned string into an array */
$pieces = explode(";", $contents) ;
/*Retrieve values from the array and assign them into variables */
$country = $pieces['4'] ;
$city = $pieces['6'] ;
$city2 = $pieces['5'] ;
$date = date("Y-m-d") ;
$time = date("H:i:s") ;
$ip = $_SERVER['REMOTE_ADDR'] ;
$query_string = $_SERVER['QUERY_STRING'] ;
$http_referer = isset( $_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : "no referer" ;
$http_user_agent = isset($_SERVER['HTTP_USER_AGENT']) ? $_SERVER['HTTP_USER_AGENT'] : "no User-agent" ;
$web_page = $_SERVER['SCRIPT_NAME'] ;
$isbot = is_Bot() ? '1' : '0' ;

/* Connect to the database --- set your credentials  ---  */
$connection = new mysqli("localhost", "root", "", "test");
/* check connection */
if (mysqli_connect_errno()) {
    printf("Connection failed: %s", mysqli_connect_error());
    exit();
		}

/* Insert data into mysql - table  */
mysqli_query($connection,  "INSERT INTO  `visitor_tracker` (`country` ,`city`,`date` ,`time`,`ip` ,`web_page` ,`query_string` ,`http_referer` ,`http_user_agent` ,`is_bot`) VALUES ('$country','$city',  '$date', '$time', '$ip', '$web_page',  '$query_string', '$http_referer', '$http_user_agent','$isbot'
)") ;
/* close DB-connection */
mysqli_close($connection) ;

/* Remove this line on production pages */
echo "Your IP is :" . $ip  . "and database is updated " ;

/* Detect if visitor is a "bot" */
function is_bot() {
$botlist = getBotList() ;
foreach($botlist as $bot) {
if(strpos($_SERVER['HTTP_USER_AGENT'] , $bot) !== false)
return true ;
	}
return false ;
	}//end function is_bot

/* Parse the robotId.txt file into an array */
function getBotList(){
if (($handle = fopen("robotid.txt", "r")) !== FALSE) {
//$count= 1 ; // for debuging
$bots = array() ;
while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
	if (strchr($data[0] , "robot-id:")) {
	//echo $count ." $data[0]".""; // for debuging
	$botId = substr("$data[0]", 9) . "" ;
	array_push($bots, "$botId") ;
	//$count++ ; // for debuging
	}
	}
fclose($handle);
return $bots ;
	}
	} // end function getBotList

?>

Wamp server has  the curl()  extension not enabled by default , go to wamp-tray -> PHP ->PHP-extensions -> Enable curl  .

Building an interface to get access to these recorded information , is simple and out of the scope of this article .

Download the source code .

The downloaded code is a “7z” archive , it implements the LZMA compression algorithm . Compression ratio of this algorithm is 30-50% better than the ZIP format . For *nix like operating systems use “7z” utility to decompress the downloaded source code of this article . Most likely this utility isn’t installed by default on any Linux distribution . For instance , on my CentOs 6.xx machine , I installed the package with :
yum install p7zip-plugins p7zip 
7z x Build-visitor-tracking-system-with-PHP.7z .