How do you debug RPC service failing to produce HAL JSON output?

Questions API Tools
1

I’m trying to set up an RPC service , but I simply can’t get the metadata_map to work.

I have set up the metadata_map to the best of my abilities in the api-tools-hal section of module.config.php, but the output is limited to object data, but no _links section is displayed containing the HAL self and href keys.

In order to debug this I have tried attaching the HAL events and see the data going in and out of the different events, but the only event I can hook onto successfully is the renderEntity event.

How on earth are you supposed to debug this? No error messages, no warnings, no nothing…

2

You just have to look at it in the clouds!

3

Well, I was hoping for something a bit more specific. :slight_smile:

4

Welcome to the forums :slight_smile:

Have you tried xdebug?
No clouds involved, pinky promise ;D

5

Hi @jAsgeir , perhaps more details or showing some code would help to get the context, but from what I can understand you are looking for something like this.

        /** @var \Laminas\ApiTools\Hal\Plugin\Hal $halPlugin*/
        $halPlugin = $this->getPluginManager()->get('Hal');

        return new ViewModel([
            //  'payload' => $halPlugin->createEntity($entity)
            'payload' => $halPlugin->createCollection($collection)
        ]);
6

I am trying to hooking up the Hal events from Module.php, onBootstrap function, but as soon as I try to grab the Hal helper (), I render the Admin UI “Unable to fetch the rpc services”:
public function onBootstrap($e)
{
$app = $e->getTarget();
$services = $app->getServiceManager();
$helpers = $services->get(‘ViewHelperManager’);
$hal = $helpers->get(‘Hal’);

8 
public function onBootstrap($e)
{
    $app = $e->getTarget();
    $services = $app->getServiceManager();
    $helpers = $services->get(‘ViewHelperManager’);
    $hal = $helpers->get(‘Hal’);
9

It’s not in the Module.php onBootstrap function, but in your RPC Controller Action (extends AbstractActionController).

here a simple example.

<?php
namespace Sports\V1\Rpc\PlayersByTeam;

use Laminas\ApiTools\ContentNegotiation\ViewModel;
use Laminas\Mvc\Controller\AbstractActionController;
use Sports\V1\Rest\Player\PlayerTable;

class ProfileToInvoiceController extends AbstractActionController
{
    /**
     * @var PlayerTable $playerTable
     */
    private PlayerTable $playerTable;
    /**
     * @param PlayerTable $playerTable
     */
    public function __construct(
        PlayerTable $playerTable
    )
    {
        $this->playerTable = $playerTable;
    }

    public function playersByTeamAction()
    {
        $team = $this->queryParam("team");
        /** @var \Sports\V1\Rest\Player\PlayerCollection $playerCollection */
        $playerCollection = $this->playerTable->fetchCollection(['team'=> $team]);

        /** @var \Laminas\ApiTools\Hal\Plugin\Hal $halPlugin*/
        $halPlugin = $this->getPluginManager()->get('Hal');

        return new ViewModel([
            'payload' => $halPlugin->createCollection($playerCollection)
        ]);
     }
}
10

Thnx, jpoitras.

I was initially working with the Laminas Api Tools framework, but I’m now using the MVC framework. Thus I have been using the Hal-plugin, and after reading some code in the plugin I found out how to fill the _embedded and _links elements with sensible data.

So far, I’m adding the self links to the elements being displayed by way of the entityRender event, since I would like to include the self link in all my entities:

    public function onBootstrap($e)
    {
        $app = $e->getTarget();
        $services = $app->getServiceManager();
        $helpers  = $services->get('ViewHelperManager');
        $hal      = $helpers->get('Hal');
        $hal->getEventManager()->attach('renderEntity', [$this, 'onRenderEntity']);
    }

    public function onRenderEntity($e)
    {
        $halEntity = $e->getParam('entity');
        $entity = $halEntity->getEntity();
        $entityClassname = get_class($entity);
        $aClassnameElements = preg_split('#\\\\#', $entityClassname);
        $classname = strtolower(array_pop($aClassnameElements));
        $classpath = implode("\\", $aClassnameElements);
        if ($classpath == "SPModel")
        {
            $routename = 'home/' . $classname;
            $routeidentifier = $classname . "_id"; 
            $halEntity->getLinks()->add(\Laminas\ApiTools\Hal\Link\Link::factory([
                'rel' => 'self',
                'route' => [
                    'name' => $routename,
                    'params' => [
                        $routeidentifier => $entity->getId()
                        ] 
                    ],
                ])
            );
        } else {
            return;
        }
    }

I am using the ArraySerializable hydrator, and the most sensible way of adding _embedded entities I have found to be to add the entities directly in my model, in the getArrayCopy() hydrating function:

    public function getArrayCopy()
    {
        $aValues = $this->toArray();

        $criteria = new Criteria();
        $criteria->add("translation.type_id", [1, 2], Criteria::EQUAL);

        $propelTranslations = $this->getTranslations($criteria);
        $aTranslations = [];
        foreach ($propelTranslations as $propelTranslation)
        {
            $aTranslations[] = new \Laminas\ApiTools\Hal\Entity($propelTranslation, $propelTranslation->getId());
        }
        $halTranslations = new \Laminas\ApiTools\Hal\Collection($aTranslations);
        $aValues['Translations'] = $halTranslations;

        $propelTips = $this->getTipss();
        $aTips = [];
        foreach ($propelTips as $propelTip)
        {
            $aTips[] = new \Laminas\ApiTools\Hal\Entity($propelTip, $propelTip->getId());
        }
        $halTips = new \Laminas\ApiTools\Hal\Collection($aTips);
        $aValues['Tips'] = $halTips;

        return $aValues;
    }

If this is the most sensible way of doing things is an open question, and I’d appreciate any comments or advice on the matter… :slight_smile: