Saving PHP sessions in Postgres Database.

> Disclaimer: Storing sessions in PHP via files(default) and other caching systems like Memcache / memcached / Redis is definitely faster but there was this use case where I had to use RDBMS for storing sessions and hence this. Use this only when it is a strict requirement to save sessions in a relational database

Single file (PGSessions.php)

Requirements:

• PostgreSQL 9.5+ [Dependency on using UPSERT]
• PHP 7.0+ (Might be compatible with 5.4 plus but not tested)
• \PDO Connected Database Object

• Create "sessions" database as provided below.

  CREATE TABLE "sessions" ( "id" TEXT NOT NULL UNIQUE, "last_updated" BIGINT NOT NULL, "expiry" bigint NOT NULL, "data" TEXT NOT NULL); CREATE INDEX "valid_sessions" ON "sessions"("id"); CREATE INDEX "nonexpired_sessions" ON "sessions"("id","expiry");

Steps to use:

• Pass the PDO Connected to the class constructor.

• Define SESSION_DURATION constants to set session expiry.

  SESSION_DURATION -> Expiry of sessions in number of seconds.

Demo

require_once 'PGSessions.php';

$pdo_connection = new PDO(...);

use \PGSessions\PGSessions;
$sessions_handler = new PGSessions($pdo_connection);
session_set_save_handler($sessions_handler, true);
session_name('MySessionName');
session_start();
session_regenerate_id(true);

$_SESSION['something'] = 'foo';
$_SESSION['something_else'] = 'bar';
echo session_id(),'<br/>',$_SESSION['something'],'<br />',$_SESSION['something_else'] ;
/*
Rest of your script
.
.
.
.
.
.
.
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.
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Before ending your script
*/
session_write_close();
//Note that session_write_close is not REQUIRED to be called on each page since we register_shutdown_function=true (second parameter = true in  session_set_save_handler).