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  * Local capabilities
  51  * ------------------
  52  *
  53  * If your local customisations require their own capabilities, use
  54  *
  55  * local/db/access.php
  56  *
  57  * You should create an array called $local_capabilities, which looks like:
  58  *
  59  * $local_capabilities = array(
  60  *         'moodle/local:capability' => array(
  61  *         'captype' => 'read',
  62  *         'contextlevel' => CONTEXT_SYSTEM,
  63  *      ),
  64  * );
  65  *
  66  * Note that for all local capabilities you add, you'll need to add language strings.
  67  * Moodle will expect to find them in local/lang/en_utf8/local.php (eg for English)
  68  * with a key (following the above example) of local:capability
  69  * See the next section for local language support.
  70  *
  71  *
  72  * Local language support
  73  * ----------------------
  74  *
  75  * Moodle supports looking in the local/ directory for language files.
  76  * You would need to create local/lang/en_utf8/local.php
  77  * and then could call strings like get_string('key', 'local');
  78  * Make sure you don't call the language file something that moodle already has one of,
  79  * stick to local or $clientname)
  80  *
  81  *
  82  * Local admin menu items
  83  * ----------------------
  84  *
  85  * It is possible to add new items to the admin_tree block.
  86  * To do this, create a file, local/settings.php
  87  * which can access the $ADMIN variable directly and add things to it.
  88  * You might do something like:
  89  * $ADMIN->add('root', new admin_category($name, $title);
  90  * $ADMIN->add('foo', new admin_externalpage($name, $title, $url, $cap);
  91  *
  92  *
  93  * Course deletion
  94  * ---------------
  95  *
  96  * To have your local customisations notified when a course is deleted,
  97  * make a file called
  98  *
  99  * local/lib.php
 100  *
 101  * In there, implement the function local_delete_course($courseid). This
 102  * function will then be called whenever the functions remove_course_contents()
 103  * or delete_course() from moodlelib are called.
 104  */
 105
 106 /**
 107  * This function checks to see whether local database customisations are up-to-date
 108  * by comparing $CFG->local_version to the variable $local_version defined in
 109  * local/version.php. If not, it looks for a function called 'xmldb_local_upgrade'
 110  * in a file called 'local/db/upgrade.php', and if it's there calls it with the
 111  * appropiate $oldversion parameter. Then it updates $CFG->local_version.
 112  * On success it prints a continue link. On failure it prints an error.
 113  *
 114  * @uses $CFG
 115  * @uses $db to do something really evil with the debug setting that should probably be eliminated. TODO!
 116  * @param string $continueto a URL passed to print_continue() if the local upgrades succeed.
 117  */
 118 function upgrade_local_db($continueto) {
 119
 120     global $CFG, $db;
 121
 122     // if we don't have code version or a db upgrade file, just return true, we're unneeded
 123     if (!file_exists($CFG->dirroot.'/local/version.php') || !file_exists($CFG->dirroot.'/local/db/upgrade.php')) {
 124         return true;
 125     }
 126
 127     require_once ($CFG->dirroot .'/local/version.php');  // Get code versions
 128
 129     if (empty($CFG->local_version)) { // normally we'd install, but just replay all the upgrades.
 130         $CFG->local_version = 0;
 131     }
 132
 133     if ($local_version > $CFG->local_version) { // upgrade!
 134         $strdatabaseupgrades = get_string('databaseupgrades');
 135         print_header($strdatabaseupgrades, $strdatabaseupgrades,
 136             build_navigation(array(array('name' => $strdatabaseupgrades, 'link' => null, 'type' => 'misc'))), '', upgrade_get_javascript());
 137
 138         upgrade_log_start();
 139         require_once ($CFG->dirroot .'/local/db/upgrade.php');
 140
 141         $db->debug=true;
 142         if (xmldb_local_upgrade($CFG->local_version)) {
 143             $db->debug=false;
 144             if (set_config('local_version', $local_version)) {
 145                 notify(get_string('databasesuccess'), 'notifysuccess');
 146                 notify(get_string('databaseupgradelocal', '', $local_version), 'notifysuccess');
 147                 print_continue($continueto);
 148                 print_footer('none');
 149                 exit;
 150             } else {
 151                 error('Upgrade of local database customisations failed! (Could not update version in config table)');
 152             }
 153         } else {
 154             $db->debug=false;
 155             error('Upgrade failed!  See local/version.php');
 156         }
 157
 158     } else if ($local_version < $CFG->local_version) {
 159         upgrade_log_start();
 160         notify('WARNING!!!  The local version you are using is OLDER than the version that made these databases!');
 161     }
 162
 163     /// Capabilities
 164     if (!update_capabilities('local')) {
 165         error('Could not set up the capabilities for local!');
 166     }
 167
 168     upgrade_log_finish();
 169 }
 170
 171 /**
 172  * Notify local code that a course is being deleted.
 173  * Look for a function local_delete_course() in a file called
 174  * local/lib.php andn call it if it is there.
 175  *
 176  * @param int $courseid the course that is being deleted.
 177  * @param bool $showfeedback Whether to display notifications on success.
 178  * @return false if local_delete_course failed, or true if
 179  *          there was noting to do or local_delete_course succeeded.
 180  */
 181 function notify_local_delete_course($courseid, $showfeedback) {
 182     global $CFG;
 183     $localfile = $CFG->dirroot .'/local/lib.php';
 184     if (file_exists($localfile)) {
 185         require_once($localfile);
 186         if (function_exists('local_delete_course')) {
 187             if (local_delete_course($courseid)) {
 188                 if ($showfeedback) {
 189                     notify(get_string('deleted') . ' local data');
 190                 }
 191             } else {
 192                 return false;
 193             }
 194         }
 195     }
 196     return true;
 197 }
 198 ?>