Use Iterator or array? - php

Question

I mostly use Iterators because I return multiple objects (new X(new Y(new Z(new A)));) and without using iterator it could drain a lot memory. My code:
<?php
namespace Bulletpoint\Model\Wiki;
use Nette\Caching\IStorage;
final class CachedBulletpoints implements Bulletpoints {
private $origin;
private $storage;
public function __construct(Bulletpoints $origin, IStorage $storage) {
$this->origin = $origin;
$this->storage = $storage;
}
public function iterate(): \Iterator {
$key = __CLASS__ . '::' . __FUNCTION__;
if($this->storage->read($key) === null) {
$this->storage->write(
$key,
iterator_to_array($this->origin->iterate()),
[]
);
}
return new \ArrayIterator($this->storage->read($key));
}
public function add(string $content, InformationSource $source) {
$this->origin->add($content, $source);
}
}
Then, another class, which can be wrapped by CachedBulletpoints:
<?php
namespace Bulletpoint\Model\Wiki;
use Bulletpoint\Model\Storage;
final class MySqlBulletpoints implements Bulletpoints {
private $database;
public function __construct(Storage\Database $database) {
$this->database = $database;
}
public function iterate(): \Iterator {
$rows = $this->database->fetchAll(
'SELECT ALL'
);
foreach($rows as $row) {
yield new ConstantBulletpoint(
$row['content'],
new \DateTime($row['date'])
);
}
}
public function add(string $content, InformationSource $source) {
$this->database->query(
'JUST INSERT'
);
}
}
Usage:
<?php
$bulletpoints = new CachedBulletpoints(
new MySqlBulletpoints(new PDODatabase),
new MemoryStorage // Cache
);
$bulletpoints->iterate();
$bulletpoints->iterate();
$bulletpoints->iterate();
I am afraid of converting iterator to array, because it does not seem like a good solution and I probably entirely lose the power of Iterators here. So, should I use in this case array rather than Iterator or what should I use to cache Iterator? I have read about CachingIterator, but it does not seem like a solution for me, does it?
Thanks :)