Pyjac\ORM\DatabaseConnection

Complexity

Total Complexity

12

Size/Duplication

Total Lines	169
Duplicated Lines	0 %

Coupling/Cohesion

Components	2
Dependencies	4

Importance

Changes	6
Bugs	2	Features	1

8 Methods

Rating	Name	Duplication	Size	Complexity
A	getDefaultOptions()	0	4	1
A	setDefaultOptions()	0	4	1
A	__construct()	0	9	1
A	getInstance()	0	8	2
A	createConnection()	0	16	2
A	tryAgainIfCausedByLostConnection()	0	8	2
A	causedByLostConnection()	0	15	1
A	loadEnv()	0	7	2

<?php

namespace Pyjac\ORM;

use PDO;

class DatabaseConnection implements DatabaseConnectionInterface
{
    /**
     * The instance of this class.
     *
     * @var Pyjac\ORM\DatabaseConnection.
     */
    private static $instance;

    /**
     * The PDO database connection in use.
     *
     * @var \PDO
     */
    public $databaseConnection;

    /**
     * The configuration values.
     *
     * @var array
     */
    private $config;

    /**
     * The default PDO connection options.
     *
     * @var array
     */
    protected $options = [
        PDO::ATTR_CASE              => PDO::CASE_NATURAL,
        PDO::ATTR_ERRMODE           => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_ORACLE_NULLS      => PDO::NULL_NATURAL,
        PDO::ATTR_STRINGIFY_FETCHES => false,
        PDO::ATTR_EMULATE_PREPARES  => false,
    ];

    /**
     * Create a new Database Connection.
     *
     * @param DatabaseConnectionStringFactoryInterface $dbConnStringFactory
     */
    public function __construct(DatabaseConnectionStringFactoryInterface $dbConnStringFactory)
    {
        $this->loadEnv(); // load the environment variables
        $neededValues = ['DRIVER', 'HOSTNAME', 'USERNAME', 'PASSWORD', 'DBNAME', 'PORT'];
        //Extract needed environment variables from the $_ENV global array
        $this->config = array_intersect_key($_SERVER, array_flip($neededValues));
        $dsn = $dbConnStringFactory->createDatabaseSourceString($this->config);
        $this->databaseConnection = $this->createConnection($dsn);
    }

    /**
     * Get the instance of the class.
     *
     * @return Pyjac\ORM\DatabaseConnection
     */
    public static function getInstance()
    {
        if (self::$instance === null) {
            self::$instance = new self(new DatabaseConnectionStringFactory());
        }

        return self::$instance;
    }

    /**
     * Create a new PDO connection.
     *
     * @param string $dsn
     *
     * @return \PDO
     */
    public function createConnection($dsn)
    {
        $username = $this->config['USERNAME'];

        $password = $this->config['PASSWORD'];

        try {
            $pdo = new PDO($dsn, $username, $password, $this->options);
        } catch (\Exception $e) {
            $pdo = $this->tryAgainIfCausedByLostConnection(
                $e, $dsn, $username, $password, $this->options
            );
        }

        return $pdo;
    }

    /**
     * Get the default PDO connection options.
     *
     * @return array
     */
    public function getDefaultOptions()
    {
        return $this->options;
    }

    /**
     * Set the default PDO connection options.
     *
     * @param array $options
     *
     * @return void
     */
    public function setDefaultOptions(array $options)
    {
        $this->options = $options;
    }

    /**
     * Handle a exception that occurred during connect execution.
     *
     * @param \Exception $e
     * @param string     $dsn
     * @param string     $username
     * @param string     $password
     * @param array      $options
     *
     * @throws \Exception
     *
     * @return \PDO
     */
    protected function tryAgainIfCausedByLostConnection(\Exception $e, $dsn, $username, $password, $options)
    {
        if ($this->causedByLostConnection($e)) {
            return new PDO($dsn, $username, $password, $options);
        }

        throw $e;
    }

    /**
     * Determine if the given exception was caused by a lost connection.
     *
     * @param \Exception $e
     *
     * @return bool
     */
    protected function causedByLostConnection(\Exception $e)
    {
        $message = $e->getMessage();

        return Helpers::contains($message, [
            'server has gone away',
            'no connection to the server',
            'Lost connection',
            'is dead or not enabled',
            'Error while sending',
            'decryption failed or bad record mac',
            'SSL connection has been closed unexpectedly',
            'Deadlock found when trying to get lock',
        ]);
    }

     /**
      * Load needed configuration values from the .env file using Dotenv.
      *
      * @return void
      */
     public function loadEnv()
     {
         if (!getenv('APP_ENV')) {
             $dotenv = new \Dotenv\Dotenv(__DIR__.'/../../../');
             $dotenv->overload();
         }
     }
}