includes/actions/FormlessAction.php

   1 <?php
   2 /**
   3  * Base classes for actions done on pages.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  18  *
  19  * @file
  20  */
  21
  22 /**
  23  * @defgroup Actions Action done on pages
  24  */
  25
  26 /**
  27  * An action which just does something, without showing a form first.
  28  */
  29 abstract class FormlessAction extends Action {
  30
  31         /**
  32          * Show something on GET request.
  33          * @return string|null Will be added to the HTMLForm if present, or just added to the
  34          *     output if not.  Return null to not add anything
  35          */
  36         abstract public function onView();
  37
  38         /**
  39          * We don't want an HTMLForm
  40          * @return bool
  41          */
  42         protected function getFormFields() {
  43                 return false;
  44         }
  45
  46         /**
  47          * @param array $data
  48          * @return bool
  49          */
  50         public function onSubmit( $data ) {
  51                 return false;
  52         }
  53
  54         /**
  55          * @return bool
  56          */
  57         public function onSuccess() {
  58                 return false;
  59         }
  60
  61         public function show() {
  62                 $this->setHeaders();
  63
  64                 // This will throw exceptions if there's a problem
  65                 $this->checkCanExecute( $this->getUser() );
  66
  67                 $this->getOutput()->addHTML( $this->onView() );
  68         }
  69
  70         /**
  71          * Execute the action silently, not giving any output.  Since these actions don't have
  72          * forms, they probably won't have any data, but some (eg rollback) may do
  73          * @param array $data Values that would normally be in the GET request
  74          * @param bool $captureErrors Whether to catch exceptions and just return false
  75          * @throws ErrorPageError|Exception
  76          * @return bool Whether execution was successful
  77          */
  78         public function execute( array $data = null, $captureErrors = true ) {
  79                 try {
  80                         // Set a new context so output doesn't leak.
  81                         $this->context = clone $this->getContext();
  82                         if ( is_array( $data ) ) {
  83                                 $this->context->setRequest( new FauxRequest( $data, false ) );
  84                         }
  85
  86                         // This will throw exceptions if there's a problem
  87                         $this->checkCanExecute( $this->getUser() );
  88
  89                         $this->onView();
  90                         return true;
  91                 }
  92                 catch ( ErrorPageError $e ) {
  93                         if ( $captureErrors ) {
  94                                 return false;
  95                         } else {
  96                                 throw $e;
  97                         }
  98                 }
  99         }
 100 }