lib/locallib.php

   1 <?php
   2 /**
   3  * This file provides hooks from moodle core into custom code.
   4  *
   5  * Important note
   6  * --------------
   7  *
   8  * If at all possible, the facilities provided here should not be used.
   9  * Wherever possible, customisations should be written using one of the
  10  * standard plug-in points like modules, blocks, auth plugins, themes, ...
  11  *
  12  * However, sometimes that is just not possible, because of the nature
  13  * of the change you want to make. In which case the second best plan is
  14  * to implement your feature in a generally useful way, which can
  15  * be contributed back to the moodle project so that everyone benefits.
  16  *
  17  * But supposing you are forced to implement some nasty hack that only
  18  * you will ever want, then the local folder is for you. The idea is that
  19  * instead of scattering your changes throughout the code base, you
  20  * put them all in a folder called 'local'. Then you won't have to
  21  * deal with merging problems when you upgrade the rest of your moodle
  22  * installation.
  23  *
  24  *
  25  * Available hooks
  26  * ===============
  27  *
  28  * These are similar to the module interface, however, not all the the
  29  * facilities that are available to modules are available to local code (yet).
  30  *
  31  *
  32  * Local database customisations
  33  * -----------------------------
  34  *
  35  * If your local customisations require changes to the database, use the files:
  36  *
  37  * local/version.php
  38  * local/db/upgrade.php
  39  *
  40  * In the file version.php, set the variable $local_version to a versionstamp
  41  * value like 2006030300 (a concatenation of year, month, day, serial).
  42  *
  43  * In the file upgrade.php, implement the
  44  * function xmldb_local_upgrade($oldversion) to make the database changes.
  45  *
  46  * Note that you don't need to have an install.xml file. Instead,
  47  * when your moodle instance is first installed, xmldb_local_upgrade() will be called
  48  * with $oldversion set to 0, so that all the updates run.
  49  *
  50  *
  51  * Course deletion
  52  * ---------------
  53  *
  54  * To have your local customisations notified when a course is deleted,
  55  * make a file called
  56  *
  57  * local/lib.php
  58  *
  59  * In there, implement the function local_delete_course($courseid). This
  60  * function will then be called whenever the functions remove_course_contents()
  61  * or delete_course() from moodlelib are called.
  62  */
  63
  64 /**
  65  * This function checks to see whether local database customisations are up-to-date
  66  * by comparing $CFG->local_version to the variable $local_version defined in
  67  * local/version.php. If not, it looks for a function called 'xmldb_local_upgrade'
  68  * in a file called 'local/db/upgrade.php', and if it's there calls it with the
  69  * appropiate $oldversion parameter. Then it updates $CFG->local_version.
  70  * On success it prints a continue link. On failure it prints an error.
  71  *
  72  * @uses $CFG
  73  * @uses $db to do something really evil with the debug setting that should probably be eliminated. TODO!
  74  * @param string $continueto a URL passed to print_continue() if the local upgrades succeed.
  75  */
  76 function upgrade_local_db($continueto) {
  77
  78     global $CFG, $db;
  79
  80     // if we don't have code version or a db upgrade file, just return true, we're unneeded
  81     if (!file_exists($CFG->dirroot.'/local/version.php') || !file_exists($CFG->dirroot.'/local/db/upgrade.php')) {
  82         return true;
  83     }
  84
  85     require_once ($CFG->dirroot .'/local/version.php');  // Get code versions
  86
  87     if (empty($CFG->local_version)) { // normally we'd install, but just replay all the upgrades.
  88         $CFG->local_version = 0;
  89     }
  90
  91     if ($local_version > $CFG->local_version) { // upgrade!
  92         $strdatabaseupgrades = get_string('databaseupgrades');
  93         print_header($strdatabaseupgrades, $strdatabaseupgrades, $strdatabaseupgrades, '', upgrade_get_javascript());
  94
  95         upgrade_log_start();
  96         require_once ($CFG->dirroot .'/local/db/upgrade.php');
  97
  98         $db->debug=true;
  99         if (xmldb_local_upgrade($CFG->local_version)) {
 100             $db->debug=false;
 101             if (set_config('local_version', $local_version)) {
 102                 notify(get_string('databasesuccess'), 'notifysuccess');
 103                 notify(get_string('databaseupgradelocal', '', $local_version), 'notifysuccess');
 104                 print_continue($continueto);
 105                 print_footer('none');
 106                 exit;
 107             } else {
 108                 error('Upgrade of local database customisations failed! (Could not update version in config table)');
 109             }
 110         } else {
 111             $db->debug=false;
 112             error('Upgrade failed!  See local/version.php');
 113         }
 114
 115     } else if ($local_version < $CFG->local_version) {
 116         upgrade_log_start();
 117         notify('WARNING!!!  The local version you are using is OLDER than the version that made these databases!');
 118     }
 119     upgrade_log_finish();
 120 }
 121
 122 /**
 123  * Notify local code that a course is being deleted.
 124  * Look for a function local_delete_course() in a file called
 125  * local/lib.php andn call it if it is there.
 126  *
 127  * @param int $courseid the course that is being deleted.
 128  * @param bool $showfeedback Whether to display notifications on success.
 129  * @return false if local_delete_course failed, or true if
 130  *          there was noting to do or local_delete_course succeeded.
 131  */
 132 function notify_local_delete_course($courseid, $showfeedback) {
 133     global $CFG;
 134     $localfile = $CFG->dirroot .'/local/lib.php';
 135     if (file_exists($localfile)) {
 136         require_once($localfile);
 137         if (function_exists('local_delete_course')) {
 138             if (local_delete_course($courseid)) {
 139                 if ($showfeedback) {
 140                     notify(get_string('deleted') . ' local data');
 141                 }
 142             } else {
 143                 return false;
 144             }
 145         }
 146     }
 147     return true;
 148 }
 149 ?>