interface ViewsHandlerInterface

interface ViewsHandlerInterface extends ViewsPluginInterface {
    
    /**
     * Run before the view is built.
     *
     * This gives all the handlers some time to set up before any handler has
     * been fully run.
     */
    public function preQuery();
    
    /**
     * Determines the entity type used by this handler.
     *
     * If this handler uses a relationship, the base class of the relationship is
     * taken into account.
     *
     * @return string
     *   The machine name of the entity type.
     */
    public function getEntityType();
    
    /**
     * Determines if the handler is considered 'broken'.
     *
     * Broken means it's a placeholder used when a handler can't be found.
     */
    public function broken();
    
    /**
     * Ensures that the main table for this handler is in the query.
     *
     * This is used a lot.
     */
    public function ensureMyTable();
    
    /**
     * Check whether given user has access to this handler.
     *
     * @param \Drupal\Core\Session\AccountInterface $account
     *   The user account to check.
     *
     * @return bool
     *   TRUE if the user has access to the handler, FALSE otherwise.
     */
    public function access(AccountInterface $account);
    
    /**
     * Get the join object that should be used for this handler.
     *
     * This method isn't used a great deal, but it's very handy for easily
     * getting the join if it is necessary to make some changes to it, such
     * as adding an 'extra'.
     */
    public function getJoin();
    
    /**
     * Sanitize the value for output.
     *
     * @param $value
     *   The value being rendered.
     * @param $type
     *   The type of sanitization needed. If not provided,
     *   \Drupal\Component\Utility\Html::escape() is used.
     *
     * @return \Drupal\views\Render\ViewsRenderPipelineMarkup
     *   Returns the safe value.
     */
    public function sanitizeValue($value, $type = NULL);
    
    /**
     * Fetches a handler to join one table to a primary table from the data cache.
     *
     * @param string $table
     *   The table to join from.
     * @param string $base_table
     *   The table to join to.
     *
     * @return \Drupal\views\Plugin\views\join\JoinPluginBase
     */
    public static function getTableJoin($table, $base_table);
    
    /**
     * Shortcut to get a handler's raw field value.
     *
     * This should be overridden for handlers with formulae or other
     * non-standard fields. Because this takes an argument, fields
     * overriding this can just call return parent::getField($formula)
     */
    public function getField($field = NULL);
    
    /**
     * Run after the view is executed, before the result is cached.
     *
     * This gives all the handlers some time to modify values. This is primarily
     * used so that handlers that pull up secondary data can put it in the
     * $values so that the raw data can be used externally.
     */
    public function postExecute(&$values);
    
    /**
     * Shortcut to display the exposed options form.
     *
     * @param array $form
     *   The form array to alter, passed by reference.
     * @param \Drupal\Core\Form\FormStateInterface $form_state
     *   The current state of the form.
     */
    public function showExposeForm(&$form, FormStateInterface $form_state);
    
    /**
     * Sets up any needed relationship.
     *
     * This is called just prior to query().
     */
    public function setRelationship();
    
    /**
     * Return a string representing this handler's name in the UI.
     */
    public function adminLabel($short = FALSE);
    
    /**
     * Breaks x,y,z and x+y+z into an array.
     *
     * @param string $str
     *   The string to split.
     * @param bool $force_int
     *   Enforce a numeric check.
     *
     * @return object
     *   A stdClass object containing value and operator properties.
     */
    public static function breakString($str, $force_int = FALSE);
    
    /**
     * Provide text for the administrative summary.
     */
    public function adminSummary();

}