10_Events.md

Events

Datahub GraphQL events are based on the Symfony event dispatcher, and are triggered during execution of Query and Mutation requests. Read more about events on Pimcore documentation.

All Datahub events are defined as a constant on component classes:

• Query
• Mutation
• Executor
• Listing
• Ouput cache

Event Subscriber examples

With Symfony, you can listen to events using either Event Listeners or Event Subscribers. Event Subscribers are used in the examples below.

Create a new class in src/AppBundle/EventListener/GraphQlSubscriber.php and use autoconfigure: true in your service configuration file (app/config/services.yml or src/AppBundle/Resources/config/services.yml) to let Symfony automatically recognize it as an Event Subscriber, either under _defaults or directly with the service:

services:
    _defaults: # Defaults for this file
        autoconfigure: true  # Let Symfony automatically configure Event Subscribers, Commands etc.
        # ...

    AppBundle\EventListener\:
        resource: '../../EventListener'

Example 1: Query & Mutation execution

<?php

namespace AppBundle\EventListener;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\ExecutorEvents;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\ExecutorEvent;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\ExecutorResultEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class GraphQlSubscriber implements EventSubscriberInterface
{
    /**
     * @inheritDoc
     */
    public static function getSubscribedEvents()
    {
        return [
            ExecutorEvents::PRE_EXECUTE => 'onPreExecute', //Pre execute on Query & Mutation
            ExecutorEvents::POST_EXECUTE => 'onPostExecute' //Post execute on Query & Mutation
        ];
    }

    /**
     * @param ExecutorEvent $event
     */
    public function onPreExecute(ExecutorEvent $event)
    {
        // do something with the query or schema
        $query = $event->getQuery();
        $schema = $event->getSchema();
    }

    /**
     * @param ExecutorResultEvent $event
     */
    public function onPostExecute(ExecutorResultEvent $event)
    {
        // do something with output result
        $result = $event->getResult();
    }
}

Example 2: Bypass workspace permissions with Query/Mutation build events

<?php

namespace AppBundle\EventListener;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\MutationEvents;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\MutationTypeEvent;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\QueryTypeEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class GraphQlSubscriber implements EventSubscriberInterface
{
    /**
     * @inheritDoc
     */
    public static function getSubscribedEvents()
    {
        return [
            MutationEvents::PRE_BUILD => 'onMutationPreBuild',
            QueryEvents::PRE_BUILD => 'onQueryPreBuild'
        ];
    }

    /**
     * @param MutationTypeEvent $event
     */
    public function onMutationPreBuild(MutationTypeEvent $event)
    {
        $mutationType = $event->getMutationType();
        $mutationType->setOmitPermissionCheck(true); //omit permission check for mutations
    }

    /**
     * @param QueryTypeEvent $event
     */
    public function onQueryPreBuild(QueryTypeEvent $event)
    {
        $queryType = $event->getQueryType();
        $queryType->setOmitPermissionCheck(true); //omit permission check for queries
    }
}

Example 3: Add custom arguments to existing types

<?php

namespace AppBundle\EventListener;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\MutationEvents;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\MutationTypeEvent;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\QueryTypeEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use GraphQL\Type\Definition\Type;

class GraphQlSubscriber implements EventSubscriberInterface
{
    /**
     * @inheritDoc
     */
    public static function getSubscribedEvents()
    {
        return [
            MutationEvents::POST_BUILD => 'onMutationPostBuild',
            QueryEvents::POST_BUILD => 'onQueryPostBuild'
        ];
    }

    /**
     * @param MutationTypeEvent $event
     */
    public function onMutationPostBuild(MutationTypeEvent $event)
    {
        $config = $event->getConfig();
        
        //additional check for a field value
        $config['fields']['createProduct']['args']['foo'] = [
            'type' => Type::nonNull(Type::string())
        ];
        
        //additional checks for input fields
        $input = $config['fields']['createProduct']['args']['input'];
        $input->config['fields']['foo'] = [
            'type' => Type::nonNull(Type::string())
        ];
        $event->setConfig($config);
    }

    /**
     * @param QueryTypeEvent $event
     */
    public function onQueryPostBuild(QueryTypeEvent $event)
    {
        $config = $event->getConfig();
        $config['fields']['getProductListing']['args']['foo'] = [
            'type'  => Type::boolean()
        ];
        $event->setConfig($config);
    }
}

Example 4: Add custom query conditions to object listing

• For global SQL conditions also General Settings
• For simple filter conditions also see Filtering

<?php

namespace AppBundle\EventListener;
use Pimcore\Model\DataObject\Service;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\ListingEvents;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\ListingEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class GraphQlSubscriber implements EventSubscriberInterface
{
    /**
     * @inheritDoc
     */
    public static function getSubscribedEvents()
    {
        return [
            ListingEvents::PRE_LOAD => 'onListingPreLoad',
        ];
    }

    /**
     * @param ListingEvent $event
     */
    public function onListingPreLoad(ListingEvent $event)
    {
        $listing = $event->getListing();

        if ($listing->getClassName() === 'Product') {
          $listing->setCondition(sprintf('(%s IN (SELECT %s FROM objects WHERE %s=\'object\') AND %s = \'variant\')',
          Service::getVersionDependentDatabaseColumnName('o_parentid'),
          Service::getVersionDependentDatabaseColumnName('o_id'),
          Service::getVersionDependentDatabaseColumnName('o_type'),
          Service::getVersionDependentDatabaseColumnName('o_type')));
        }

        $event->setListing($listing);
    }
}

Example 5: Add custom conditions to enable/disable output (responses) cache per request

• OutputCacheEvents::PRE_LOAD: is triggered before trying to load an entry from cache, if cache is enabled. You can disable the cache for this request by setting $event->setUseCache(false). If you disable the cache, the entry won't be loaded nor saved
• OutputCacheEvents::PRE_SAVE: if cache is enabled, it's triggered before saving an entry into the cache. You can use it to modify the response before it gets saved.

<?php

namespace AppBundle\EventListener;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\OutputCachePreLoadEvent;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\Model\OutputCachePreSaveEvent;
use Pimcore\Bundle\DataHubBundle\Event\GraphQL\OutputCacheEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class GraphqlListener implements EventSubscriberInterface
{
    /**
     * @inheritDoc
     */
    public static function getSubscribedEvents()
    {
        return [
            OutputCacheEvents::PRE_LOAD => 'onPreLoadCache',
            OutputCacheEvents::PRE_SAVE => 'onPreSaveCache'
        ];
    }

    /**
     * @param OutputCachePreLoadEvent $event
     */
    public function onPreLoadCache(OutputCachePreLoadEvent $event) 
    {
        $uri = $event->getRequest()->getMethod();
        
        if(str_contains($uri, "my-special-endpoint"))
        {
            $event->setUseCache(false);
        }
    }

    /**
     * @param OutputCachePreSaveEvent $event
     */
    public function onPreSaveCache(OutputCachePreSaveEvent $event) 
    {
        $uri = $event->getRequest()->getMethod();
        
        if(str_contains($uri, "my-awesome-endpoint"))
        {
            $response = $event->getResponse();
            // modify the response as you want it to be saved...

            $event->setResponse($response);
        }
    }
}