Session_set_save_handler not writing to database - php

Question

I'm currently learning php and trying to write session data to my database without success.
I have a setup with Apache24, PHP 7 environment and Postgresql database.
When I instantiate sessionhandling class ($sess = new sessionhandling) in my other PHP file nothing is written to database. However, when I pass variable to and call the write function ($sess->write), data is written to the database.
(Hope this is not a duplicate of any other questions raised. Done a lot of searches on Stackoverflow and Google, but not found any answers that solve my challenge)
My session handler code is as follows:
<?php
Include(dirname(__DIR__).'\Userstories\db\Connection.php');
class sessionhandling extends Connecting implements SessionHandlerInterface {
public function __construct(){
// Set handler to overide SESSION
session_set_save_handler(
array(&$this, "open"),
array(&$this, "close"),
array(&$this, "read"),
array(&$this, "write"),
array(&$this, "destroy"),
array(&$this, "gc")
);
register_shutdown_function('session_write_close');
// Start the session
session_start();
session_write_close;
}
public function open($save_path, $id) {
if(self::get()->connect()) {
return true;
} else {
return false;
}
}
public function close() {
if(self::get()->connect()->pdo = Null) {
return true;
} else {
return false;
}
}
public function read($id) {
//$pdo = Connecting::get()->connect();
$ipdo = self::get()->connect();
$q_udata = "SELECT data FROM sessions WHERE id=:id";
$stmt=$ipdo->prepare($q_udata);
$stmt->bindvalue(':id', $id);
$stmt->execute();
if($stmt->execute()) {
$row = $stmt->fetch(PDO::FETCH_ASSOC);
$ipdo = NULL;
return $row['data'];
} else {
$ipdo = NULL;
return '';
}
}
public function write($id, $data){
$id = (string) $id;
$data = (string) $data;
$access = time();
$ipdo = self::get()->connect();
$c_id = "SELECT id FROM sessions WHERE id=:id";
$stmt=$ipdo->prepare($c_id);
$stmt->bindvalue(':id', $id);
$stmt->execute();
$idarray=$stmt->fetch(PDO::FETCH_ASSOC);
$row_id = $idarray['id'];
if(empty($row_id)) {
$sessionids = 'INSERT INTO sessions(id, data, access) VALUES(:id, :data, :access)';
$stmt = $ipdo->prepare($sessionids);
$stmt->bindvalue(':id', $id);
$stmt->bindvalue(':access', $access);
$stmt->bindvalue(':data', $data);
$stmt->execute();
session_write_close();
} else {
$rep_data = "UPDATE sessions SET data = :data, access = :access WHERE id = :id";
$stmt=$ipdo->prepare($rep_data);
$stmt->bindvalue(':id', $id);
$stmt->bindvalue(':access', $access);
$stmt->bindvalue(':data', $data);
$stmt->execute();
session_write_close();
}
if($stmt->execute()) {
$ipdo = NULL;
return true;
} else {
$ipdo = NULL;
return false;
}
}
public function destroy($id) {
$ipdo = self::get()->connect();
$del_data = "DELETE FROM sessions WHERE id =:id";
$stmt = $ipdo->prepare($del_data);
$stmt->bindvalue(':id', $id);
$stmt->execute();
if($stmt->execute()) {
$ipdo = NULL;
return true;
} else {
$ipdo = NULL;
return false;
}
}
public function gc($max) {
$old = time() - $max;
$ipdo = self::get()->connect();
$cleanup = "DELETE * FROM sessions WHERE access < :old";
$stmt = $ipdo->prepare($cleanup);
$stmt->bindvalue(':old', $old);
$stmt->execute();
if($stmt->execute()) {
$ipdo = NULL;
return true;
} else {
$ipdo = NULL;
return false;
}
}
}
?>
When I remove the 'implements SessionHandlerInterface' sessionhandling class and remove the parameters $save_path, $id from open function, I get the following error: "Warning: session_start(): Failed to read session data: user (path: ) in C:\Users\Public\Server\Apache24\htdocs\Userstories\sessionhandling.php on line 19"
Is it reuiqred to define the $save_path when using DB for session handling? If so, what should the $save_path be?
Any advise on how to get my session handler to write to DB is very much appreciated.

Answer 1

I made ut work by changing my read function to this and ensuring that a string is returned:
public function read($id) {
//$pdo = Connecting::get()->connect();
$ipdo = self::get()->connect();
$q_udata = "SELECT data FROM sessions WHERE id=:id";
$stmt=$ipdo->prepare($q_udata);
$stmt->bindvalue(':id', $id);
$stmt->execute();
if($stmt->execute()) {
$row = $stmt->fetch(\PDO::FETCH_ASSOC);
$ipdo = NULL;
$data = $row['data'];
return (string) $data;
} else {
$ipdo = NULL;
return '';
}
}
I know this has been pointed out in other posts, but I thought that my $data = $row['data'] would return a string in the first place.