Support for other database drivers such as SQLite #EnhancementRequest

[klor]

"The best PDO wrapper" can be improved by adding support for other database drivers such as SQLite. This can be done by introducing two new variables: DB_DRIVER and DB_PATH.

// SQLite example
define('DB_DRIVER', 'sqlite');
define('DB_PATH', '/data/songs.db');

// Another SQLite example
define('DB_DRIVER', 'sqlite');
define('DB_PATH', ':memory:');

// These are all valid DSN strings for SQLite and should be supported.
$dsn = 'sqlite:c:\full\path\to\name.db';
$dsn = 'sqlite:..\data\name.db';
$dsn = 'sqlite:name.db';

The variables will be used in the DB::instance() method, something along these lines (untested code):

if(!defined('DB_DRIVER')) {
    define('DB_DRIVER','mysql');
}

if(DB_DRIVER=='sqlite') {
    $dsn = 'sqlite:'.DB_PATH;
} else {
    $dsn = DB_DRIVER.':host='.DB_HOST.';dbname='.DB_NAME.';charset='.DB_CHAR;
}

---

On a side-note, you may also consider introducing a single DB_DSN variable that can be used instead of DB_HOST, DB_NAME and DB_CHAR.

define('DB_DSN', 'sqlite:/data/songs.db');
define('DB_DSN', 'sqlite::memory:');
define('DB_DSN', "mysql:host=localhost;dbname=test;charset=utf8");

Why? Because I like the idea of having full access to the DSN string.
My config.php could then look like this:

$environment = "dev";
if($environment=="prod") {
    define('DB_DSN', "sqlite:/data/songs.db");
} else {
    define('DB_DSN', "sqlite:/path/to/data/songs.db");
}

And,

$environment = "dev";
if($environment=="prod") {
    define('DB_DSN', "mysql:host=localhost;dbname=test;charset=utf8");
    define('DB_USER', 'myuser');
    define('DB_PASS', '4321');
} else {
    define('DB_DSN', "mysql:host=localhost;dbname=test;charset=utf8");
    define('DB_USER', 'root');
    define('DB_PASS', '1234');
}

Instead of:

if($environment=="prod") {
    define('DB_HOST', 'localhost');
    define('DB_NAME', 'test');
    define('DB_CHAR', 'utf8');
    define('DB_USER', 'myuser');
    define('DB_PASS', '4321');
} else {
    define('DB_HOST', 'localhost');
    define('DB_NAME', 'test');
    define('DB_CHAR', 'utf8');
    define('DB_USER', 'root');
    define('DB_PASS', '1234');
}