ContextDefinitionInterface.php

<?php

namespace Drupal\rules\Context;

use Drupal\Core\Plugin\Context\ContextDefinitionInterface as ContextDefinitionInterfaceCore;

/**
 * Context definition information required by Rules.
 *
 * The core interface is extended to add properties that are necessary for
 * Rules.
 */
interface ContextDefinitionInterface extends ContextDefinitionInterfaceCore {
    
    /**
     * Constants for the context assignment restriction mode.
     *
     * @see ::getAssignmentRestriction()
     */
    const ASSIGNMENT_RESTRICTION_INPUT = 'input';
    const ASSIGNMENT_RESTRICTION_SELECTOR = 'selector';
    
    /**
     * Determines if the context value is allowed to be NULL.
     *
     * @return bool
     *   TRUE if NULL values are allowed, FALSE otherwise.
     */
    public function isAllowedNull();
    
    /**
     * Sets the "allow NULL value" behavior.
     *
     * @param bool $null_allowed
     *   TRUE if NULL values should be allowed, FALSE otherwise.
     *
     * @return $this
     */
    public function setAllowNull($null_allowed);
    
    /**
     * Determines if this context has an assignment restriction.
     *
     * @return string|null
     *   Either ASSIGNMENT_RESTRICTION_INPUT for contexts that are only allowed to
     *   be provided as input values, ASSIGNMENT_RESTRICTION_SELECTOR for contexts
     *   that must be provided as data selectors or NULL if there is no
     *   restriction for this context.
     */
    public function getAssignmentRestriction();
    
    /**
     * Sets the assignment restriction mode for this context.
     *
     * @param string|null $restriction
     *   Either ASSIGNMENT_RESTRICTION_INPUT for contexts that are only allowed to
     *   be provided as input values, ASSIGNMENT_RESTRICTION_SELECTOR for contexts
     *   that must be provided as data selectors or NULL if there is no
     *   restriction for this context.
     *
     * @return $this
     */
    public function setAssignmentRestriction($restriction);
    
    /**
     * Exports the definition as an array.
     *
     * @return array
     *   An array with values for all definition keys.
     */
    public function toArray();

}