What is the proper syntax to get a db instance? - php

Question

I use eloquent outside laravel.
Here is the file responsible of it:
class DbSql
{
public function db()
{
$capsule = new Capsule;
$capsule->addConnection( [
'driver' => Settings::DATABASE_DRIVER,
'host' => Settings::DATABASE_HOST,
'database' => Settings::DATABASE_NAME,
'username' => Settings::DATABASE_USERNAME,
'password' => Settings::DATABASE_PASSWORD,
'charset' => 'utf8',
'collation' => 'utf8_unicode_ci',
'prefix' => ''
] );
# Make this Capsule instance available globally
$capsule->setAsGlobal();
return $capsule;
}
}
In controllers, I instantiate the instance once, and may use it several time in a controller:
$dbInstance = ( new DbSql() )->db(); // Create the instance
// Instance usages:
$images = $dbInstance->table( 'images_attachments' )->where...
$files = $dbInstance->table( 'files' )->where...
.....
Should I instantiate with:
$dbInstance = ( new DbSql() )->db(); as in the code above
or with:
$dbInstance = ( new DbSql() )->db()->getConnection();
what's the proper way ?

Answer 1

First of all, there is no need to wrap the Capsule (which is a Illuminate\Database\Capsule\Manager instance) in another class to make easier to retrieve it. In fact, the Illuminate\Database\Capsule\Manager provides a singleton instance and simple accessors.
Once you call
$capsule->setAsGlobal();
the Capsule instance will be accessible statically from everywhere via Capsule::.
This because the setAsGlobal() method, under the hood, does simply this:
static::$instance = $this;
Saving the instance in a static class variable to retrieve it on subsequent calls to Capsule::.
So, once you call setAsGlobal(), it is possible to do, for example:
Capsule::select('select * from user');
and you'll get the results of the query on the previously created connection.
However, you can see that the select method doesn't exists on the Manager (alias Capsule) class.
Why does it works?
Because the Manager class overrides the __callStatic() php magic method
class Manager
{
use CapsuleManagerTrait;
// ...
public static function __callStatic($method, $parameters)
{
return static::connection()->$method(...$parameters);
}
}
So the call to select() method is redirected to the underlying \Illuminate\Database\Connection instance automagically.
This means that:
there is no need to wrap the Manager/Capsule in an external class, since it is already a wrapper over the Connection class. No need to add another wrapper.
If you prefer to wrap it, however, I suggest you to returning the Manager/Capsule instance and not the underlying connection, since the suggested approach in the docs is to work directly with the Manager