JAQB\ConnectionManager

Complexity

Total Complexity

17

Size/Duplication

Total Lines	150
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	2

Importance

Changes

0

6 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	4	1
A	get()	0	14	3
A	getDefault()	0	8	2
A	add()	0	10	2
B	buildFromConfig()	0	21	5
A	buildDsn()	0	17	4

<?php

/**
 * @author Jared King <j@jaredtking.com>
 *
 * @see http://jaredtking.com
 *
 * @copyright 2015 Jared King
 * @license MIT
 */

namespace JAQB;

use InvalidArgumentException;
use JAQB\Exception\JAQBException;
use PDO;

/**
 * This class manages one or more PDO database connections.
 */
class ConnectionManager
{
    /**
     * @var array
     */
    private $config;

    /**
     * @var array
     */
    private $connections = [];

    /**
     * @var array
     */
    private static $connectionParams = [
        'host' => 'host',
        'port' => 'port',
        'name' => 'dbname',
        'charset' => 'charset',
    ];

    /**
     * @param array $config
     */
    public function __construct(array $config = [])
    {
        $this->config = $config;
    }

    /**
     * Gets a database connection by ID.
     *
     * @param string $id
     *
     * @throws JAQBException if the connection does not exist
     *
     * @return QueryBuilder
     */
    public function get($id)
    {
        if (isset($this->connections[$id])) {
            return $this->connections[$id];
        }

        if (!isset($this->config[$id])) {
            throw new JAQBException('No configuration or connection has been supplied for the ID "'.$id.'".');
        }

        $this->connections[$id] = $this->buildFromConfig($this->config[$id], $id);

        return $this->connections[$id];
    }

    /**
     * Gets the default database connection.
     *
     * @throws JAQBException if there is not a default connection
     *
     * @return QueryBuilder
     */
    public function getDefault()
    {
        if (count($this->connections) === 1) {
            return reset($this->connections);
        }

        throw new JAQBException('There is no default connection.');
    }

    /**
     * Adds a connection.
     *
     * @param string       $id
     * @param QueryBuilder $connection
     *
     * @throws InvalidArgumentException if a connection with the given ID already exists
     *
     * @return $this
     */
    public function add($id, QueryBuilder $connection)
    {
        if (isset($this->connections[$id])) {
            throw new InvalidArgumentException('A connection with the ID "'.$id.'" already exists.');
        }

        $this->connections[$id] = $connection;

        return $this;
    }

    /**
     * Builds a new query builder instance from a configuration.
     * NOTE: This is not intended to be used outside of this class.
     *
     * @param array  $config
     * @param string $id
     *
     * @return QueryBuilder
     */
    public function buildFromConfig(array $config, $id)
    {
        // generate the dsn needed for PDO
        if (isset($config['dsn'])) {
            $dsn = $config['dsn'];
        } else {
            $dsn = $this->buildDsn($config, $id);
        }

        $user = isset($config['user']) ? $config['user'] : null;
        $password = isset($config['password']) ? $config['password'] : null;

        $options = [];
        if (isset($config['errorMode'])) {
            $options[PDO::ATTR_ERRMODE] = $config['errorMode'];
        }

        $pdo = new PDO($dsn, $user, $password, $options);

        return new QueryBuilder($pdo);
    }

    /**
     * Builds a PDO DSN string from a JAQB connection configuration.
     *
     * @param array  $config
     * @param string $id     configuration ID
     *
     * @throws JAQBException if the configuration is invalid
     *
     * @return string
     */
    public function buildDsn(array $config, $id)
    {
        if (!isset($config['type'])) {
            throw new JAQBException('Missing connection type for configuration "'.$id.'"!');
        }

        $dsn = $config['type'].':';
        $params = [];
        foreach (self::$connectionParams as $j => $k) {
            if (isset($config[$j])) {
                $params[] = $k.'='.$config[$j];
            }
        }
        $dsn .= implode(';', $params);

        return $dsn;
    }
}