Merge pull request #895 from Geeklog-Core/feature/new-session-class

Feature/new session class

system/classes/Session.php

@@ -0,0 +1,200 @@
+<?php
+
+namespace Geeklog;
+
+/**
+ * Class Session
+ *
+ * @package Geeklog
+ */
+abstract class Session
+{
+    // Index of $_SESSION array
+    const GL_NAMESPACE = '__gl';
+    const VAR_NAMESPACE = '__v';
+    const FLASH_NAMESPACE = '__f';
+
+    // Lifespan of the session in seconds
+    const LIFE_SPAN = 60 * 60 * 2;
+
+    // Anonymous user id
+    const ANON_USER_ID = 1;
+
+    /**
+     * Session options
+     *
+     * @var array
+     */
+    private static $options = [];
+
+    /**
+     * "flash", i.e., one-time session variables
+     *
+     * @var array
+     */
+    private static $flashVars = [];
+
+    /**
+     * The flag to show if the class is initialized
+     *
+     * @var bool
+     */
+    private static $isInitialized = false;
+
+    /**
+     * Init the Session class
+     *
+     * @param array $options
+     */
+    public static function init(array $options = [])
+    {
+        if (self::$isInitialized) {
+            return;
+        }
+
+        // Save options
+        self::$options = $options;
+
+        // Set PHP settings
+        ini_set('session.use_strict_mode', 1);
+        ini_set('session.use_cookies', 1);
+        ini_set('session.use_only_cookies', 1);
+        ini_set('session.use_trans_sid', 0);
+
+        // Start a new session
+        if (!session_start()) {
+            die(__METHOD__ . ': Cannot start session.');
+        }
+
+        // Check if the user is new
+        if (!isset($_SESSION[self::GL_NAMESPACE])
+            || ($_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['uid'] < self::ANON_USER_ID)
+            || self::isExpires()) {
+            $_SESSION[self::GL_NAMESPACE] = [
+                self::FLASH_NAMESPACE => [],
+                self::VAR_NAMESPACE   => [
+                    'uid' => self::ANON_USER_ID,
+                ],
+            ];
+        }
+
+        // Move "flash" session vars to the property of the class
+        if (isset($_SESSION[self::GL_NAMESPACE][self::FLASH_NAMESPACE])
+            && is_array($_SESSION[self::GL_NAMESPACE][self::FLASH_NAMESPACE])) {
+            self::$flashVars = $_SESSION[self::GL_NAMESPACE][self::FLASH_NAMESPACE];
+        }
+        $_SESSION[self::GL_NAMESPACE][self::FLASH_NAMESPACE] = [];
+
+        // Update life span
+        $_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['expiresAt'] = time() + self::LIFE_SPAN;
+
+        // Finished initialization
+        self::$isInitialized = true;
+    }
+
+    /**
+     * Return if the current session has expired
+     *
+     * @return bool
+     */
+    public static function isExpires()
+    {
+        return isset($_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['expiresAt'])
+            && is_int($_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['expiresAt'])
+            && ($_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['expiresAt']) < time();
+    }
+
+    /**
+     * Return if the current user is anonymous
+     *
+     * @return bool
+     */
+    public static function isLoggedIn()
+    {
+        return ($_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['uid'] > self::ANON_USER_ID);
+    }
+
+    /**
+     * Return the current user id
+     *
+     * @return int
+     */
+    public static function getUid()
+    {
+        return (int) $_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['uid'];
+    }
+
+    /**
+     * Set the current user id
+     *
+     * @param  int $uid
+     * @throws \InvalidArgumentException
+     */
+    public static function setUid($uid)
+    {
+        $uid = (int) $uid;
+
+        if ($uid >= self::ANON_USER_ID) {
+            $_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE]['uid'] = $uid;
+            self::regenerate();
+        } else {
+            throw new \InvalidArgumentException('User id must be ' . self::ANON_USER_ID . ' or greater.');
+        }
+    }
+
+    /**
+     * Set a session value
+     *
+     * @param  string $name
+     * @param  mixed  $value
+     */
+    public static function set($name, $value)
+    {
+        $_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE][$name] = $value;
+    }
+
+    /**
+     * Set a "flash" session value
+     *
+     * @param  string $name
+     * @param  mixed  $value
+     */
+    public static function setFlash($name, $value)
+    {
+        $_SESSION[self::GL_NAMESPACE][self::FLASH_NAMESPACE][$name] = $value;
+    }
+
+    /**
+     * Get a session value
+     *
+     * @param  string $name
+     * @param  mixed  $defaultValue
+     * @return mixed
+     */
+    public static function get($name, $defaultValue = null)
+    {
+        return isset($_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE][$name])
+            ? $_SESSION[self::GL_NAMESPACE][self::VAR_NAMESPACE][$name]
+            : $defaultValue;
+    }
+
+    /**
+     * Get a "flash" session value
+     *
+     * @param  string $name
+     * @param  mixed  $defaultValue
+     * @return mixed
+     */
+    public static function getFlash($name, $defaultValue = null)
+    {
+        return isset(self::$flashVars[$name]) ? self::$flashVars[$name] : $defaultValue;
+    }
+
+    /**
+     * Regenerate the session id
+     */
+    public static function regenerate()
+    {
+        session_regenerate_id(false);
+    }
+}