PHP Session Management
| From: | CDitty | Date: | Sun, 23 Mar 2003 14:50:14 +0000 |
| Subject: | PHP Session Management | ||
| Groups: | php.general | ||
| Request: | Send a blank email to php-general+get-140755@lists.php.net to get a copy of this message | ||
Hello all. I am trying to figure out some session management that is in the O'reilly book - Web Database Applications. I am getting the following error - Error 1045 : Access denied for user: 'userid@localhost' (Using password: YES)
Normally, I would think that this is because the userid and/or password for the database is incorrect. However, they are not. I have verified that the userid and password are correct and the database server is active.
Anyone have any ideas?
Here is the code....
sessions.php
---------------------
<?
// Database connection information
$hostName = "localhost";
$databaseName = "development";
$username = "userid";
$password = "password";
// Error handling
function showerror()
{
die("Error " . mysql_errno() . " : " . mysql_error());
}
// Returns current time as a number
// Used for recording the last session access
function getMicroTime()
{
// microtime() returns the number of seconds
// since 0:00:00 January 1, 1970 GMT as a
// microsecond part and a second part.
// eg: 0.08344800 1000952237
// Convert the two parts into an array
$mtime = explode(" ", microtime());
// Return the addition of the two parts
return($mtime[1] + $mtime[0]);
}
// The database connection
$connection;
// The global variable that holds the table name
$session_table;
function sessionOpen($database_name, $table_name)
{
// Save the database name in a global variable
global $connection;
global $hostName;
global $username;
global $password;
if(!($connection = @mysql_connect($hostName, $username, $password))){
showerror();
}
if(!mysql_select_db($database_name, $connection)){
showerror();
}
// Save the table name in a global variable
global $session_table;
$session_table = $table_name;
return true;} // This function is called whenever a session_start() // call is made and reads the session variables // Returns "" when a session is not found // (serialized)string - session exists function sessionRead($sess_id) {
// Access the DB connection
global $connection;
// Access the global variable that holds the name
// of the table that holds the session variables
global $session_table;
// Formulate a query to find the session
// identified by $sess_id
$search_query = "select * from $session_table where session_id = '$sess_id'";
// Execute the query
if(!($result = @mysql_query($search_query, $connection))){
showerror();
}
if(mydql_num_rows($result) == 0){
return "";
}else{
// Found a session - retun the seialized string
$row = mysql_fetch_array($result);
return $row["session_variable"];
}
}
// This function is called when a session is initialized
// with a session_start() call, when variables are
// registered or unregistered, and when session variables
// are modified. Returns true on success.
function sessionWrite($sess_id, $val)
{
global $connection;
global $session_table;
$time_stamp = getMicroTime();
$search_query = "select session_id from $session_table where session_id = '$sess_id'";
// Execute query
if(!($result = @mysql_query($search_query, $connection))){
showerror();
}
if(mysql_num_rows($result) == 0){
// No session found, insert a new one
$insert_query = "insert into $session_table (session_id, session_variable, last_accessed) values ('$sess_id, '$val', $time_stamp)";
if(!mysql_query($insert_query, $connection)){
showerror();
}
}else{
// Existing session found - Update it
$update_query = "update $session_table set session_variable = '$val', last_accessed = $time_stamp where session_id = '$sess_id'";
if(!mysql_query($update_query, $connection)){
showerror();
}
}
return true;
}
// This funstion is executed on shutdown of the session
// Always returns true
function sessionClose($sess_id)
{
return true;} // This is called whenever the session_destroy() // funstion call is made. Returns true is the session // has successfully been deleted. function sessionDestroy($sess_id) {
global $connection;
global $session_table;
$delete_query = "delete from session_table where session_id = '$sess_id'";
if(!($result = @mysql_query($delete_query, $connection))){
showerror();
}
return true;
}
// This function is called on a session's start up with
// the probability specified in session.gc_probability.
// Performs garbage collection by removing all sessions
// that haven't been updated in the last $max_lifetime
// seconds as set in session.gc_maxlifetime.
// returns true if the delete query succeeded.
function sessionGC($max_lifetime)
{
global $connection;
global $session_table;
$time_stamp = getMicroTime();
$delete_query = "delete from $session_table where last_accessed < ($time_stamp - $max_lifetime)";
if(!($result = @mysql_query($delete_query, $connection))){
showerror();
}
return true;} // Call to register user callback functions session_set_save_handler("sessionOpen", "sessionClose", "sessionRead", "sessionWrite", "sessionDestroy", "sessionGC"); ?> Here is the calling code. sessTest.php --------------------- <? // include the sessions handlers include("sessions.php"); // initialize a session. This call either creates a new session // or re-establishes an existing one. session_start(); // if this is a new session, then the variable $count is not registered if(!session_is_registered("count")) {
session_register("count");
session_register("start");
$count = 0;
$start = time();
}else{
$count++;} $sessionId = session_id(); ?> <p>This page points at a session (<?=$sessionId ?>)<br> count = <?=$count ?>.<br> start = <?=$start ?>.<br> <p>This session has lasted <? $duration = time() - $start; echo "$duration"; ?> seconds.