優化

1. 修改 lib/accesslib.php 讓訪客權限的查詢，改用 cache。

   [root@dywang html]# diff -urN moodle/lib/accesslib.php moodle23/lib/accesslib.php
   --- moodle/lib/accesslib.php	2012-08-10 08:05:01.000000000 +0800
   +++ moodle23/lib/accesslib.php	2014-02-25 13:28:26.000000000 +0800
   @@ -256,7 +256,8 @@
     * @return array
     */
    function get_role_access($roleid) {
   -    global $DB, $ACCESSLIB_PRIVATE;
   +    global $DB, $ACCESSLIB_PRIVATE,$CFG;  //dywang
    
        /* Get it in 1 DB query...
         * - relevant role caps at the root and down
   @@ -264,6 +265,12 @@
         */
    
        //TODO: MUC - this could be cached in shared memory to speed up first page loading, web crawlers, etc.
   +    // Temporary hack for better performance http://tracker.moodle.org/browse/MDL-25288
   +    if (6 == $roleid) { // Guest role dywang 
   +        return unserialize(file_get_contents($CFG->dataroot . '/cache/guest_role_access_cache.serialized'));
   +    } else if ('update_guest_role_access' == $roleid) { // For update script
   +        $roleid = 6;
   +    }
    
        $accessdata = get_empty_accessdata();
    
   @@ -3822,7 +3829,7 @@
        if (empty($fields)) {
            $fields = 'u.id, u.confirmed, u.username, u.firstname, u.lastname, '.
                      'u.maildisplay, u.mailformat, u.maildigest, u.email, u.emailstop, u.city, '.
   -                  'u.country, u.picture, u.idnumber, u.department, u.institution, '.
   +                  'u.department, u.country, u.picture, u.idnumber, u.department, u.institution, '. //dywang
                      'u.lang, u.timezone, u.lastaccess, u.mnethostid, r.name AS rolename, r.sortorder';
        }
   

2. 撰寫建立訪客權限查詢 cache 檔的 php 程式 guest_role_access_cache_update.php 存放在 admin/cli 目錄下。

   [root@moodle moodle23]# vim admin/cli/guest_role_access_cache_update.php
   <?php
   
   define('CLI_SCRIPT', true);
   
   require_once('../../config.php');
   require_once('../../lib/accesslib.php');
   
   $accessInfo = serialize(get_role_access('update_guest_role_access'));
   $success = file_put_contents($CFG->dataroot . '/cache/guest_role_access_cache.serialized', $accessInfo);
   
   echo ($success ? "Guest role access file updated! $success bites written.\n" : "ERROR during guest access file update!\n");
   ?>
   

3. 設定例行性工作排程，定時更新 cache 資料，但出現錯誤，原因為例行工作執行時工作目錄不會在 /var/www/html/moodle23/admin/cli/，故 php 中指定相對目錄的檔找不到。

   [root@moodle moodle23]# crontab -e 
   29 * * * * php /$moodledir/moodle23/admin/cli/guest_role_access_cache_update.php
   
   PHP Warning:  require_once(../../config.php): failed to open stream: No such fil
   e or directory in /var/www/html/moodle23/admin/cli/guest_role_access_cache_updat
   e.php on line 5
   

4. 設定例行性工作排程，定時更新 cache 資料，先變換目錄再執行，結果正常。

   [root@moodle moodle23]# crontab -e 
   29 * * * * cd /var/www/html/moodle23/admin/cli && /usr/bin/php guest_role_access
   
   Guest role access file updated! 1188 bites written.