Api.php

<?php
/**
 * @author Jaap Jansma <jaap.jansma@civicoop.org>
 * @license AGPL-3.0
 */

namespace Civi\DataProcessor\Output;

use Civi\API\Event\ResolveEvent;
use Civi\API\Event\RespondEvent;
use Civi\API\Events;
use Civi\API\Provider\ProviderInterface as API_ProviderInterface;
use Civi\DataProcessor\ProcessorType\AbstractProcessorType;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class Api implements OutputInterface, API_ProviderInterface, EventSubscriberInterface{

  public function __construct() {

  }

  /**
   * @return array
   */
  public static function getSubscribedEvents() {
    // Some remarks on the solution to implement the getFields method.
    // We would like to have implemented it as a normal api call. Meaning
    // it would been processed in the invoke method.
    //
    // However the reflection provider has a stop propegation so we cannot use
    // getfields here unles we are earlier then the reflection provider.
    // We should then use a weight lower than Events::W_EARLY and do a
    // stop propegation in our event. But setting an early flag is not a neat way to do stuff.
    // So instead we use the Respond event and check in the respond event whether the action is getFields and
    // if so do our getfields stuff there.
    return array(
      Events::RESOLVE => array('onApiResolve'),
      //Events::RESPOND => array('onGetFieldsRepsonse'), // we use this method to add our field definition to the getFields action.
    );
  }

  public function onApiResolve(ResolveEvent $event) {
    $apiRequest = $event->getApiRequest();
    if (strtolower($apiRequest['entity']) == 'dataprocessorapi') {
      $event->setApiProvider($this);
    }
  }

  /**
   * @param array $apiRequest
   *   The full description of the API request.
   * @return array
   *   structured response data (per civicrm_api3_create_success)
   * @see civicrm_api3_create_success
   * @throws \API_Exception
   */
  public function invoke($apiRequest) {
    // Check whether we do a count...
    $dataProcessorName = $apiRequest['action'];
    $isCountAction = false;
    if (stripos($apiRequest['action'], 'getcount') === 0) {
      $isCountAction = true;
      $dataProcessorName = substr($apiRequest['action'], 8);
    }
    // Find the form processor
    $dataProcessor = \CRM_Dataprocessor_BAO_DataProcessor::getDataProcessorByOutputTypeAndName('api', $dataProcessorName);
    if (!$dataProcessor instanceof AbstractProcessorType) {
      throw new \API_Exception('Could not find a form processor');
    }

    if ($isCountAction) {
      $count = $dataProcessor->getDataFlow()->recordCount();
      return array('count' => $count, 'is_error' => 0);
    } else {
      $options = _civicrm_api3_get_options_from_params($apiRequest['params']);
      if (isset($options['limit'])) {
        $dataProcessor->getDataFlow()->setLimit($options['limit']);
      }
      if (isset($options['offset'])) {
        $dataProcessor->getDataFlow()->setOffset($options['offset']);
      }

      $records = $dataProcessor->getDataFlow()->allRecords();
      $values = array();
      foreach($records as $idx => $record) {
        foreach($record as $fieldname => $field) {
          $values[$idx][$fieldname] = $field->formattedValue;
        }
      }
      $return = array(
        'values' => $values,
        'count' => count($values),
        'is_error' => 0,
      );
      if (isset($apiRequest['params']['debug']) && $apiRequest['params']['debug']) {
        $return['debug_info'] = $dataProcessor->getDataFlow()->getDebugInformation();
      }
      return $return;
    }
  }

  /**
   * @param int $version
   *   API version.
   * @return array<string>
   */
  public function getEntityNames($version) {
    return array(
      'DataProcessorApi'
    );
  }

  /**
   * @param int $version
   *   API version.
   * @param string $entity
   *   API entity.
   * @return array<string>
   */
  public function getActionNames($version, $entity) {
    if (strtolower($entity) != 'dataprocessorapi') {
      return array();
    }
    $params['is_active'] = 1;
    $data_processors = \CRM_Dataprocessor_BAO_DataProcessor::getValues($params);
    $actions[] = 'getfields';
    foreach($data_processors as $data_processor) {
      $actions[] = $data_processor['name'];
      $actions[] = 'getcount'.$data_processor['name'];
    }
    return $actions;
  }


}