ignace

This design has no cohesion. If you look at ClientCollection and UnregisteredClient you see they are both aware of the internals of your clientList, that it has a property Client and that it is a stdClass.
 
Every class involved is made aware of a LengthPrefixStream.
 
Do not branch out of your code until it is absolutely necessary. Keep the clientList and connStream and all of that inside $server.
 
With your Client class you are on the right track.

You need to programmatically log in. Something like this:
 

function getSessionCookie($username, $password) { $context = [ 'http' => [ 'method' => 'POST', 'content' => http_build_query(['username_formfield' => $username, 'password_formfield' => $password]), ] ]; $contents = file_get_contents('http://apiwebsite.com/login', false, $context); if (false === $contents) { return false; } foreach ($http_response_header as $header) { if (0 === strpos($header, 'Set-Cookie')) { return explode(':', $header)[1]; } } return false; } function queryApi($sessionCookie, $apiCall) { $context = [ 'http' => [ 'header' => ["Cookie: $sessionCookie"], ] ]; $contents = file_get_contents('http://apiwebsite.com/blah?latest', false, $context); // your code } You'll still need to handle if the cookie expires etc.. and probably also need to parse the set-cookie header instead of simply copy-pasting. But this should get you started.

Yes. Your field name should explain it's value:
public function buildForm(FormBuilderInterface $builder, array $options) { $builder ->add( 'game', EntityType::class, [ 'class' => 'AppBundle:Game', 'choice_label' => 'name', 'label' => 'name' ] ) ->add( 'type', EntityType::class, [ 'class' => 'AppBundle:Type', 'choice_label' => 'name', 'multiple' => false, 'expanded' => false ] ); } Afterwards you can access these fields like:
$form->get('game') // and $form->get('type')

Kinda, it would be something like:
 

class Quote { private $id; // .. other fields private $price; public function setId($id) { $this->id = $id; } public function getId() { return $this->id; } // get*, set* for the other fields public function setPrice($price) { $this->price = $price; } public function getPrice() { return $this->price; } }Then you would create a query and populate this object: 

$sql = 'SELECT id, .., price FROM quotes'; $stmt = $this->db->prepare($sql); foreach ($stmt->fetchAll() as $row) { $quotes[] = $quote = new Quote; $quote->setId($row['id']); $quote->setPrice($row['price']); } return $quotes;At this point you can work with this object as: 

$quote->getId(); $quote->getPrice();Now before you start writing all of this yourself, there are frameworks available online that do this sort of thing for you. A list can be found here:https://github.com/ziadoz/awesome-php#database