会话跟踪_使用会话注册和跟踪用户

会话跟踪

In effect this is a session handler that registers sessions inside a database and verifies them based on a timestamp (session timeout). This code is just an skeleton that needs to be extended and altered to your own needs.

实际上，这是一个会话处理程序，用于在数据库内部注册会话并根据时间戳（会话超时）进行验证。 此代码只是一个框架，需要对其进行扩展和更改以适应您自己的需求。

Installing is done in two steps.

安装分两步完成。

First, create this table inside your mysql server.

首先，在您的mysql服务器中创建此表。

Next create a new PHP file including the attached code snippet.

接下来，创建一个新PHP文件，包括附带的代码片段。

<?php 
class Sessions{
	private $id;			#Will contain the session ID generated from the inser ID in the database
	private $CTS;			#Holds the "Current Timeout"
	private $dbname;		#Database name that contains the session table
	private $dbhost;		#Database host that contains the deatabase containing the session table
	private $dbuser;		#Database user used to connect to the database.
	private $dbpass;		#Database Password used to connect to the database, assuming that one is always used.
	private $dblink;		#Strict var used to hold the link identifier created on database connect.
	private $timeout; 
	public function __construct($dbuser, $dbpass, $dbhost, $dbname, $session_timeout=''){
		if(!empty($dbuser) && !empty($dbpass) && !empty($dbhost) && !empty($dbname)){
			$this->dbuser = $dbuser;
			$this->dbpass = $dbpass; #assuming we always use a password
			$this->dbhost = $dbhost;
			$this->dbname = $dbname;
		}
		
		// Define a timeout.
		$this->timeout = (!empty($session_timeout)) ? $session_timeout : "5";
		
		// Start our session //
		session_start();
		
		// We redirect on error, so this is to prevent a redirect loop... //
		if(!isset($_SESSION['failcount'])){
			$_SESSION['failcount'] = 0;
		}
		
		// this is our error handler :P !//
		if(isset($_SESSION['failcount'])){
			if($_SESSION['failcount'] > 10){
				$err = '';
				if(@is_array($_SESSION['errors'])){
					foreach($_SESSION['errors'] as $key => $value){
						$err .= "$key => $value<br/>";
					}
				}else{
					$err = 'unknown error!';
				}
				die('Failed 10x to setup a decent session<br/>The following errors where reported!<br/>'.$err);
			}
		}
		
		// Create the current timestamp to work with // 
		$this->CTS = ((date('d')*3600)+(date('g') * 60)+date('i'));
		
		// Create a db connection to test connectivity//
		if(!$this->dbConnect()){ 
			$_SESSION['errors']['dbconnect'] = 'failed to connect to DB';
			// Unset the session active var //
			unset($_SESSION['active']);
			// Register the fact this happend // 
			$_SESSION['failcount']++;
			header('location:'.$_SESSION['location']);
		}
		
		// Cleanup old sessions (timed out sessions) //
		$this->CleanDb();
		
		// Validate this session //
		if(!isset($_SESSION['active'])){
			if($this->RegisterSession()){
				$this->dbClose();
				return true;
			}else{
				$this->dbClose();
				return false;
			}
		}else{
			$this->VerifySession();
			$this->dbClose();
		}
	}
    
	public function getOnline(){
		$this->dbConnect();
		if(is_resource($this->dblink)){
			$sql = 'SELECT DISTINCT COUNT(*) as online FROM session';
			$result = mysql_query($sql);
			$row = mysql_fetch_array($result);
			$this->dbClose();
			if($row['online'] > 0){
				return $row['online'];
			}else{
				return 1;
			}
		}else{
			return false;
		}
	}
	
	// Get number of minutes online
	public function getBrowseTime(){
		return $_SESSION['ttime'];
	}
	
	public function getStartTime(){
		$secs = $_SESSION['btime'] * 60;
		$hours = round(($secs  / (60 * 60) %24));
		$min = round(($secs  / 60) %60);
		return $hours .":". $min;
	}
	
	public function whoami(){
		return $_SESSION['username'];
	}
	
	// Open a database connection.
	private function dbConnect(){
		if(!empty($this->dbuser) && !empty($this->dbpass) && !empty($this->dbhost)){
			if(@$this->dblink = mysql_connect($this->dbhost, $this->dbuser, $this->dbpass)){
				if(@mysql_select_db($this->dbname, $this->dblink)){
					return $this->dblink;
				}else{
					$_SESSION['errors']['database'] = 'no valid database could be selected';
				}
			}else{
				$_SESSION['errors']['database'] = 'Connection with database failed';
			}
		}else{
			$_SESSION['errors']['database'] = 'Not all required db connection info was available';
		}
		return false;
	}
	
	private function dbClose(){
		if(is_resource($this->dblink)){
			mysql_close($this->dblink);
		}
	}
	
	// Clean up all timed out session registrations.
	private function CleanDb(){
		if(is_resource($this->dblink)){
			$sql = 'select * from session';
			$result = mysql_query($sql, $this->dblink);
			while($row = mysql_fetch_array($result)){
				$tdiff = $this->CTS - $row['sess_ltime'];
				if($tdiff >= $this->timeout){
					$delete = 'DELETE FROM session where sess_id = "'.$row['sess_id'].'"';
					mysql_query($delete);
				}
			}
		}else{
			$_SESSION['errors']['dbclean'] = 'No db link resource for cleanup';
		}
	
	}
	// Method to handle registrations // 
	private function RegisterSession(){
		// Hold all the session information available inside the _Session var.
		$_SESSION['active']    = true;
		$_SESSION['name']      = session_name();
		$_SESSION['btime']     = $this->CTS;
		$_SESSION['ltime']     = $this->CTS;
		$_SESSION['ttime']     = '1';
		$_SESSION['username']  = 'guest';
		$_SESSION['location']  = $_SERVER['REQUEST_URI'];
		
		if(is_resource($this->dblink)){
			$sql = 'INSERT INTO session(sess_name, sess_btime, sess_ltime, sess_ttime, sess_username, sess_location)
			        VALUES("'.$_SESSION['name'].'","'.$_SESSION['btime'].'","'.$_SESSION['ltime'].'",
					       "'.$_SESSION['ttime'].'","'.$_SESSION['username'].'","'.$_SESSION['location'].'")';
			if(mysql_query($sql, $this->dblink)){
				$_SESSION['id'] = mysql_insert_id();
				// If we had any failures we reset them here //
				$_SESSION['failcount'] = 0;
				return true;
			}else{
				$_SESSION['errors']['register'] = 'failed to register session inside the database, online info might not be available';
				// Unset the session active var //
				unset($_SESSION['active']);
				// Register the fact this happend // 
				$_SESSION['failcount']++;
				header('location:'.$_SESSION['location']);
			}
		}else{
			$_SESSION['errors']['register'] = 'unable to register session, no database link available';
			// Unset the session active var //
			unset($_SESSION['active']);
			// Register the fact this happend // 
			$_SESSION['failcount']++;
			header('location:'.$_SESSION['location']);
		}
	
	}
	
	private function VerifySession(){
		if(isset($_SESSION['active'])){
			if(is_resource($this->dblink)){
				$sql = 'SELECT * from session where sess_id = "'.$_SESSION['id'].'"';
				if($result = mysql_query($sql)){
					$row = mysql_fetch_array($result);
					if(isset($row['sess_id'])){
						//Verify the times again for a timeout //
						$tdiff = $this->CTS - $row['sess_ltime'];
						if($tdiff >= $this->timeout){
							// If the session timedout//
							// Delete the session from the database //
							$delete = 'DELETE FROM session where sess_id = "'.$row['sess_id'].'"';
							mysql_query($delete);
							// Unset the session active var //
							unset($_SESSION['active']);
							// Register the fact this happend // 
							$_SESSION['failcount']++;
							header('location:'.$_SESSION['location']);
						}else{
							// Hold all the session information available inside the _Session var.
							$_SESSION['ttime'] = $this->CTS - $row['sess_btime'];
							$_SESSION['ltime'] = $this->CTS;
							$_SESSION['location']  = $_SERVER['REQUEST_URI'];	
							// We need to update the fact we had activity ;-) //
							
							$update = 'UPDATE session SET sess_ltime="'.$this->CTS.'", sess_ttime="'.$_SESSION['ttime'].'", sess_location="'.$_SESSION['location'].'"
							           WHERE sess_id = "'.$_SESSION['id'].'"';
							mysql_query($update);
							return true;
						}
					}else{
						// Session was allready delete from database. Other users browsing maybe? :)
						// Handle it like a timedout session.
						unset($_SESSION['active']);
						// Register the fact this happend.
						$_SESSION['failcount']++;
						header('location:'.$_SESSION['location']);
					}
				}else{
					// The query failed for unkown reasons//
					unset($_SESSION['active']);
					// Register the fact this happend. 
					$_SESSION['failcount']++;
					header('location:'.$_SESSION['location']);
				}
			
			}else{
				$_SESSION['errors']['verify'] = 'No dblink available for verification';
				unset($_SESSION['active']);
				return false;
			}
		}else{
			die('H4(k 4t73mpt!');
		}
	}
}

For example you created a file called "session.class.php" that contains the code, you then need to upload that file to your webserver.

例如，您创建了一个名为“ session.class.php”的文件，其中包含代码，然后需要将该文件上载到Web服务器。

Next you need to guarantee that this file is loaded and initialized each time a user browses to a new location, usually this is done by including this file and initialization code to the header of your page(s).

接下来，您需要确保每次用户浏览到新位置时都加载并初始化此文件，通常这是通过在页面标题中包含此文件和初始化代码来完成的。

Including the file works like this;

包含文件的工作方式如下：

<?php
$PHPEx='.php';
include('session.class'.$PHPEx);
?>

When this is done you need to initialize the class after which you are able to access it using the following directives;

完成此操作后，您需要初始化该类，之后您可以使用以下指令访问它；

<?php
$session = new Sessions('dbuser', 'dbpass', 'dbhost', 'dbname', 'timeout in min');
echo "There are:".$session->getOnline()." users online.<br />";
echo "You started browsing at :".$session->getStartTime()."u<br />";
echo "Our current time is ".date('h:i')."u <br />";
echo "You have been active for :".$session->getBrowseTime()."Mins.<br />";
echo "You are known as :".$session->whoami()."<br />";
?>

You can also add all the snippets inside one file and include that in your application.

您还可以将所有代码片段添加到一个文件中，并将其包含在您的应用程序中。

Again, this class still needs allot of work if you want it to maintain "loggedin" users and related sessions. In this stage the "how many users are online" can be queried and own session information like how long have iv been browsing.

同样，如果您希望此类维护“已登录”用户和相关会话，则仍需要分配该类。 在此阶段，可以查询“有多少用户在线”并拥有自己的会话信息，例如iv浏览了多长时间。

Good luck on extending this class.

祝您能继续上这堂课。

Rgrds, Chris

克里斯·Rgrds

翻译自: https://www.experts-exchange.com/articles/1331/Use-sessions-to-register-and-track-users.html

会话跟踪