admin/xmldb/actions/XMLDBAction.class.php

   1 <?php // $Id$
   2
   3 ///////////////////////////////////////////////////////////////////////////
   4 //                                                                       //
   5 // NOTICE OF COPYRIGHT                                                   //
   6 //                                                                       //
   7 // Moodle - Modular Object-Oriented Dynamic Learning Environment         //
   8 //          http://moodle.com                                            //
   9 //                                                                       //
  10 // Copyright (C) 1999 onwards Martin Dougiamas        http://dougiamas.com  //
  11 //           (C) 2001-3001 Eloy Lafuente (stronk7) http://contiento.com  //
  12 //                                                                       //
  13 // This program is free software; you can redistribute it and/or modify  //
  14 // it under the terms of the GNU General Public License as published by  //
  15 // the Free Software Foundation; either version 2 of the License, or     //
  16 // (at your option) any later version.                                   //
  17 //                                                                       //
  18 // This program is distributed in the hope that it will be useful,       //
  19 // but WITHOUT ANY WARRANTY; without even the implied warranty of        //
  20 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         //
  21 // GNU General Public License for more details:                          //
  22 //                                                                       //
  23 //          http://www.gnu.org/copyleft/gpl.html                         //
  24 //                                                                       //
  25 ///////////////////////////////////////////////////////////////////////////
  26
  27 /// This is the main action class. It implements all the basic
  28 /// functionalities to be shared by each action.
  29
  30 class XMLDBAction {
  31
  32     var $does_generate;  //Type of value returned by the invoke method
  33                          //ACTION_GENERATE_HTML have contents to show
  34                          //set by each specialized invoke
  35
  36     var $title;          //Title of the Action (class name, by default)
  37                          //set by parent init automatically
  38
  39     var $str;            //Strings used by the action
  40                          //set by each specialized init, calling loadStrings
  41
  42     var $output;         //Output of the action
  43                          //set by each specialized invoke, get with getOutput
  44
  45     var $errormsg;       //Last Error produced. Check when any invoke returns false
  46                          //get with getError
  47
  48     var $postaction;     //Action to execute at the end of the invoke script
  49
  50     /**
  51      * Constructor
  52      */
  53     function XMLDBAction() {
  54         $this->init();
  55     }
  56
  57     /**
  58      * Constructor to keep PHP5 happy
  59      */
  60     function __construct() {
  61         $this->XMLDBAction();
  62     }
  63
  64     /**
  65      * Init method, every subclass will have its own,
  66      * always calling the parent one
  67      */
  68     function init() {
  69         $this->does_generate = ACTION_NONE;
  70         $this->title     = strtolower(get_class($this));
  71         $this->str       = array();
  72         $this->output    = NULL;
  73         $this->errormsg  = NULL;
  74         $this->subaction = NULL;
  75     }
  76
  77     /**
  78      * returns the type of output of the file
  79      */
  80     function getDoesGenerate() {
  81         return $this->does_generate;
  82     }
  83
  84     /**
  85      * getError method, returns the last error string.
  86      * Used if the invoke() methods returns false
  87      */
  88     function getError() {
  89         return $this->errormsg;
  90     }
  91
  92     /**
  93      * getOutput method, returns the output generated by the action.
  94      * Used after execution of the invoke() methods if they return true
  95      */
  96     function getOutput() {
  97         return $this->output;
  98     }
  99
 100     /**
 101      * getPostAtion method, returns the action to launch after executing
 102      * another one
 103      */
 104     function getPostAction() {
 105         return $this->postaction;
 106     }
 107
 108     /**
 109      * getTitle method returns the title of the action (that is part
 110      * of the $str array attribute
 111      */
 112     function getTitle() {
 113         return $this->str['title'];
 114     }
 115
 116     /**
 117      * loadStrings method, loads the required strings specified in the
 118      * array parameter
 119      */
 120     function loadStrings($strings) {
 121     /// Load some commonly used strings
 122         $this->str['title'] = get_string($this->title, 'xmldb');
 123
 124     /// Now process the $strings array loading it in the $str atribute
 125         if ($strings) {
 126             foreach ($strings as $key => $module) {
 127                 $this->str[$key] = get_string($key, $module);
 128             }
 129         }
 130     }
 131
 132     /**
 133      * main invoke method, it simply sets the postaction attribute
 134      * if possible
 135      */
 136     function invoke() {
 137
 138         global $SESSION;
 139
 140     /// If we are used any dir, save it in the lastused session object
 141     /// Some actions can use it to perform positioning
 142         if ($lastused = optional_param ('dir', NULL, PARAM_PATH)) {
 143             $SESSION->lastused = stripslashes_safe($lastused);
 144         }
 145
 146         $this->postaction = optional_param ('postaction', NULL, PARAM_ALPHAEXT);
 147     /// Avoid being recursive
 148         if ($this->title == $this->postaction) {
 149             $this->postaction = NULL;
 150         }
 151     }
 152
 153     /**
 154      * launch method, used to easily call invoke methods between actions
 155      */
 156     function launch($action) {
 157
 158         global $CFG;
 159
 160     /// Get the action path and invoke it
 161         $actionsroot = "$CFG->dirroot/$CFG->admin/xmldb/actions";
 162         $actionclass = $action . '.class.php';
 163         $actionpath = "$actionsroot/$action/$actionclass";
 164
 165     /// Load and invoke the proper action
 166         $result = false;
 167         if (file_exists($actionpath) && is_readable($actionpath)) {
 168             require_once($actionpath);
 169             if ($xmldb_action = new $action) {
 170                 $result = $xmldb_action->invoke();
 171                 if ($result) {
 172                     if ($xmldb_action->does_generate != ACTION_NONE &&
 173                         $xmldb_action->getOutput()) {
 174                         $this->does_generate = $xmldb_action->does_generate;
 175                         $this->title = $xmldb_action->title;
 176                         $this->str = $xmldb_action->str;
 177                         $this->output .= $xmldb_action->getOutput();
 178                     }
 179                 } else {
 180                     $this->errormsg = $xmldb_action->getError();
 181                 }
 182             } else {
 183                 $this->errormsg = "Error: cannot instantiate class (actions/$action/$actionclass)";
 184             }
 185         } else {
 186             $this->errormsg = "Error: wrong action specified ($action)";
 187         }
 188         return $result;
 189     }
 190 }
 191 ?>