Civi/Report/OutputHandlerFactory.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | Copyright CiviCRM LLC. All rights reserved.                        |
   5  |                                                                    |
   6  | This work is published under the GNU AGPLv3 license with some      |
   7  | permitted exceptions and without any warranty. For full license    |
   8  | and copyright information, see https://civicrm.org/licensing       |
   9  +--------------------------------------------------------------------+
  10  */
  11 namespace Civi\Report;
  12
  13 /**
  14  * OutputHandlers can either be the standard core ones: print/pdf/csv, or
  15  * extensions can add their own.
  16  *
  17  * @package Civi\Report
  18  */
  19 class OutputHandlerFactory {
  20
  21   protected static $singleton;
  22
  23   /**
  24    * @var array
  25    *   Array of registered possible OutputHandlers.
  26    */
  27   protected static $registered = [];
  28
  29   /**
  30    * Singleton function.
  31    *
  32    * @return OutputHandlerFactory
  33    */
  34   public static function singleton() {
  35     if (self::$singleton === NULL) {
  36       self::$singleton = new OutputHandlerFactory();
  37       self::registerBuiltins();
  38     }
  39     return self::$singleton;
  40   }
  41
  42   /**
  43    * Return an OutputHandler based on the parameters.
  44    *
  45    * @param \CRM_Report_Form $form
  46    *   A CiviReport that extends CRM_Report_Form.
  47    *
  48    * @return \Civi\Report\OutputHandlerInterface|NULL
  49    *   An object that implements the OutputHandlerInterface, or NULL if
  50    *   nothing suitable for the given parameters.
  51    */
  52   public function create(\CRM_Report_Form $form) {
  53     /**
  54      * The first draft of this had extensions register their classes,
  55      * but it needed to be early on because there's also the dropdown on the
  56      * report form that lists the output formats available which happens
  57      * earlier than the output run and that worked better as a simple hook.
  58      * So it just felt out of place then to have two different types of things,
  59      * and people are used to hooks, and there's already alterReportVar which
  60      * seemed a natural place.
  61      */
  62     \CRM_Utils_Hook::alterReportVar('outputhandlers', self::$registered, $form);
  63     foreach (self::$registered as $candidate) {
  64       try {
  65         $outputHandler = new $candidate();
  66         if ($outputHandler->isOutputHandlerFor($form)) {
  67           $outputHandler->setForm($form);
  68           return $outputHandler;
  69         }
  70       }
  71       catch (\Exception $e) {
  72         // no ts() since this is a sysadmin-y message
  73         \Civi::log()->warn("Unable to use $candidate as an output handler. " . $e->getMessage());
  74       }
  75     }
  76     return NULL;
  77   }
  78
  79   /**
  80    * Register an outputHandler to handle an output format.
  81    *
  82    * @param string $outputHandler
  83    *   The classname of a class that implements OutputHandlerInterface.
  84    */
  85   public function register(string $outputHandler) {
  86     // Use classname as index to (a) avoid duplicates and (b) make it easier
  87     // to unset/overwrite one via hook.
  88     self::$registered[$outputHandler] = $outputHandler;
  89   }
  90
  91   /**
  92    * There are some handlers that were hard-coded in to the form before which
  93    * have now been moved to outputhandlers.
  94    */
  95   private static function registerBuiltins() {
  96     self::$singleton->register('\CRM_Report_OutputHandler_Print');
  97     self::$singleton->register('\CRM_Report_OutputHandler_Csv');
  98     self::$singleton->register('\CRM_Report_OutputHandler_Pdf');
  99   }
 100
 101 }