Cakephp 3: React/zmq library namespace

Question

I am working on on the basic tutorial on using ratchet mentioned here http://socketo.me/docs/push.

I have created a test setup for the tutorial that works flawlessly. However, when I am trying to integrate the setup with CakePHP 3 I am running into problems. The ratchet and ZMQ servers are independent just the way mentioned in the tutorial. Only the following piece of code needs to move into CakePHP 3 controllers:

$context = new ZMQContext();
$socket = $context->getSocket(ZMQ::SOCKET_PUSH, 'my pusher');
$socket->connect("tcp://localhost:5555");
$socket->send(json_encode($entryData));

This code basically submits new data to ZMQ queue for forwarding to ratchet. If I place the same 4 lines in a plain PHP file outside CakePHP 3 codebase it works. When I place the same four lines inside APP\Controller\SamplesController it says the class APP\Controller\ZMQContext not found.

CakePHP 3 docs mention that vendor libraries installed via composer will be automatically available through autoloader. I have installed React\ZMQ library via following command:

php composer require react/zmq

I have tried accessing the class via following namespaces but none of them have worked:

ZMQContext ( Class 'App\Controller\ZMQContext' not found )
\ZMQContext ( Class 'App\Controller\ZMQ' not found )
React\ZMQ\ZMQContext ( Class 'App\Controller\React\ZMQ\ZMQContext' not found )
\React\ZMQ\ZMQContext ( Class 'React\ZMQ\ZMQContext' not found )

Probably missing out on some namespace concept in PHP but my understanding is that if ZMQContext is available in a normal PHP file through global namespace, then it should also be available within CakePHP 3 via \ZMQContext.

I have following questions:

1. How can I push data to ZMQ Queue within my CakePHP 3 APP ?
2. APP::path() & APP::classname() seems to work only for classes within the CakePHP 3 application. How to check path for a particular vendor library class ?
3. How to autoload vendor library classes correctly ? (I do not wish to require/require_once them as it will needed to be done for each controller that wants to publish data via ratchet)
4. Is the assumption about accessing global namespace via \CLASSNAME wrong ?
5. My second attempt at accessing vendor library class at \ZMQContext resolved to App\Controller\ZMQ. How is that possible when it should have attempted within root namespace ?
6. ZMQContext is not part of react/zmq library so does it mean it part of default php bindings for libzmq ?

Answer 1

This was a simple typo problem:

$context = new \ZMQContext();
$socket = $context->getSocket(\ZMQ::SOCKET_PUSH, 'my pusher');
$socket->connect("tcp://localhost:5555");
$socket->send(json_encode($entryData));

The second namespace specification in second line was missing.