VariableAdd.php

<?php

namespace Drupal\rules\Plugin\RulesAction;

use Drupal\rules\Core\RulesActionBase;

/**
 * Provides an 'Add a variable' action.
 *
 * @todo The context definition for "type" needs an options_provider list.
 *
 * @RulesAction(
 *   id = "rules_variable_add",
 *   label = @Translation("Add a variable"),
 *   category = @Translation("Data"),
 *   context_definitions = {
 *     "type" = @ContextDefinition("string",
 *       label = @Translation("Data Type"),
 *       description = @Translation("Specifies the type of the variable that should be added."),
 *       assignment_restriction = "input"
 *     ),
 *     "value" = @ContextDefinition("any",
 *       label = @Translation("Value"),
 *       description = @Translation("Optionally, specify the initial value of the variable."),
 *       required = FALSE
 *     ),
 *   },
 *   provides = {
 *     "variable_added" = @ContextDefinition("any",
 *       label = @Translation("Added variable")
 *     ),
 *   }
 * )
 */
class VariableAdd extends RulesActionBase {
    
    /**
     * Add a variable.
     *
     * @param string $type
     *   The data type the new variable is of.
     * @param mixed $value
     *   The variable to add.
     */
    protected function doExecute($type, $value) {
        $this->setProvidedValue('variable_added', $value);
    }
    
    /**
     * {@inheritdoc}
     */
    public function refineContextDefinitions(array $selected_data) {
        if ($type = $this->getContextValue('type')) {
            $this->pluginDefinition['context_definitions']['value']
                ->setDataType($type);
            $this->pluginDefinition['provides']['variable_added']
                ->setDataType($type);
        }
    }

}