initial commit

application/core/DatabaseFactory.php

@@ -0,0 +1,64 @@
+<?php
+
+/**
+ * Class DatabaseFactory
+ *
+ * Use it like this:
+ * $database = DatabaseFactory::getFactory()->getConnection();
+ *
+ * That's my personal favourite when creating a database connection.
+ * It's a slightly modified version of Jon Raphaelson's excellent answer on StackOverflow:
+ * http://stackoverflow.com/questions/130878/global-or-singleton-for-database-connection
+ *
+ * Full quote from the answer:
+ *
+ * "Then, in 6 months when your app is super famous and getting dugg and slashdotted and you decide you need more than
+ * a single connection, all you have to do is implement some pooling in the getConnection() method. Or if you decide
+ * that you want a wrapper that implements SQL logging, you can pass a PDO subclass. Or if you decide you want a new
+ * connection on every invocation, you can do do that. It's flexible, instead of rigid."
+ *
+ * Thanks! Big up, mate!
+ */
+class DatabaseFactory
+{
+    private static $factory;
+    private $database;
+
+    public static function getFactory()
+    {
+        if (!self::$factory) {
+            self::$factory = new DatabaseFactory();
+        }
+        return self::$factory;
+    }
+
+    public function getConnection() {
+        if (!$this->database) {
+
+            /**
+             * Check DB connection in try/catch block. Also when PDO is not constructed properly,
+             * prevent to exposing database host, username and password in plain text as:
+             * PDO->__construct('mysql:host=127....', 'root', '12345678', Array)
+             * by throwing custom error message
+             */
+            try {
+                $options = array(PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_OBJ, PDO::ATTR_ERRMODE => PDO::ERRMODE_WARNING);
+                $this->database = new PDO(
+                   Config::get('DB_TYPE') . ':host=' . Config::get('DB_HOST') . ';dbname=' .
+                   Config::get('DB_NAME') . ';port=' . Config::get('DB_PORT') . ';charset=' . Config::get('DB_CHARSET'),
+                   Config::get('DB_USER'), Config::get('DB_PASS'), $options
+                   );
+            } catch (PDOException $e) {
+
+                // Echo custom message. Echo error code gives you some info.
+                echo 'Database connection can not be estabilished. Please try again later.' . '<br>';
+                echo 'Error code: ' . $e->getCode();
+
+                // Stop application :(
+                // No connection, reached limit connections etc. so no point to keep it running
+                exit;
+            }
+        }
+        return $this->database;
+    }
+}