MDL-43497 Language: Allow course language to be overridden

enrol/flatfile/lib.php

@@ -399,7 +399,7 @@ class enrol_flatfile_plugin extends enrol_plugin {
      * @param bool $buffer_if_future
      */
     protected function process_records(progress_trace $trace, $action, $roleid, $user, $course, $timestart, $timeend, $buffer_if_future = true) {
-        global $CFG, $DB, $SESSION;
+        global $CFG, $DB;
 
         // Check if timestart is for future processing.
         if ($timestart > time() and $buffer_if_future) {
@@ -448,12 +448,7 @@ class enrol_flatfile_plugin extends enrol_plugin {
             }
 
             if ($notify and $this->get_config('mailstudents')) {
-                // Some nasty hackery to get strings and dates localised for target user.
+                $oldforcelang = force_current_language($user->lang);
-                $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
-                if (get_string_manager()->translation_exists($user->lang, false)) {
-                    $SESSION->lang = $user->lang;
-                    moodle_setlocale();
-                }
 
                 // Send welcome notification to enrolled users.
                 $a = new stdClass();
@@ -478,22 +473,14 @@ class enrol_flatfile_plugin extends enrol_plugin {
                     $trace->output("Failed to notify enrolled user", 1);
                 }
 
-                if ($SESSION->lang !== $sessionlang) {
+                force_current_language($oldforcelang);
-                    $SESSION->lang = $sessionlang;
-                    moodle_setlocale();
-                }
             }
 
             if ($notify and $this->get_config('mailteachers', 0)) {
                 // Notify person responsible for enrolments.
                 $enroller = $this->get_enroller($course->id);
 
-                // Some nasty hackery to get strings and dates localised for target user.
+                $oldforcelang = force_current_language($enroller->lang);
-                $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
-                if (get_string_manager()->translation_exists($enroller->lang, false)) {
-                    $SESSION->lang = $enroller->lang;
-                    moodle_setlocale();
-                }
 
                 $a = new stdClass();
                 $a->course = format_string($course->fullname, true, array('context' => $context));
@@ -517,10 +504,7 @@ class enrol_flatfile_plugin extends enrol_plugin {
                     $trace->output("Failed to notify enroller {$eventdata->userto->id}", 1);
                 }
 
-                if ($SESSION->lang !== $sessionlang) {
+                force_current_language($oldforcelang);
-                    $SESSION->lang = $sessionlang;
-                    moodle_setlocale();
-                }
             }
             return;
 

lib/authlib.php

@@ -677,7 +677,7 @@ function login_attempt_failed($user) {
  * @param stdClass $user
  */
 function login_lock_account($user) {
-    global $CFG, $SESSION;
+    global $CFG;
 
     if ($user->mnethostid != $CFG->mnet_localhost_id) {
         return;
@@ -699,12 +699,7 @@ function login_lock_account($user) {
         $secret = random_string(15);
         set_user_preference('login_lockout_secret', $secret, $user);
 
-        // Some nasty hackery to get strings and dates localised for target user.
+        $oldforcelang = force_current_language($user->lang);
-        $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
-        if (get_string_manager()->translation_exists($user->lang, false)) {
-            $SESSION->lang = $user->lang;
-            moodle_setlocale();
-        }
 
         $site = get_site();
         $supportuser = core_user::get_support_user();
@@ -725,10 +720,7 @@ function login_lock_account($user) {
             email_to_user($user, $supportuser, $subject, $message);
         }
 
-        if ($SESSION->lang !== $sessionlang) {
+        force_current_language($oldforcelang);
-            $SESSION->lang = $sessionlang;
-            moodle_setlocale();
-        }
     }
 }
 

lib/db/access.php

@@ -2013,5 +2013,12 @@ $capabilities = array(
                 'teacher'        => CAP_ALLOW,
                 'editingteacher' => CAP_ALLOW,
         )
+    ),
+
+    'moodle/site:forcelanguage' => array(
+        'captype' => 'read',
+        'contextlevel' => CONTEXT_SYSTEM,
+        'archetypes' => array(
+        )
     )
 );

lib/enrollib.php

@@ -2146,16 +2146,11 @@ abstract class enrol_plugin {
      * @param progress_trace $trace
      */
     protected function notify_expiry_enrolled($user, $ue, progress_trace $trace) {
-        global $CFG, $SESSION;
+        global $CFG;
 
         $name = $this->get_name();
 
-        // Some nasty hackery to get strings and dates localised for target user.
+        $oldforcelang = force_current_language($user->lang);
-        $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
-        if (get_string_manager()->translation_exists($user->lang, false)) {
-            $SESSION->lang = $user->lang;
-            moodle_setlocale();
-        }
 
         $enroller = $this->get_enroller($ue->enrolid);
         $context = context_course::instance($ue->courseid);
@@ -2189,10 +2184,7 @@ abstract class enrol_plugin {
             $trace->output("error notifying user $ue->userid that enrolment in course $ue->courseid expires on ".userdate($ue->timeend, '', $CFG->timezone), 1);
         }
 
-        if ($SESSION->lang !== $sessionlang) {
+        force_current_language($oldforcelang);
-            $SESSION->lang = $sessionlang;
-            moodle_setlocale();
-        }
     }
 
     /**
@@ -2207,7 +2199,7 @@ abstract class enrol_plugin {
      * @param progress_trace $trace
      */
     protected function notify_expiry_enroller($eid, $users, progress_trace $trace) {
-        global $DB, $SESSION;
+        global $DB;
 
         $name = $this->get_name();
 
@@ -2218,12 +2210,7 @@ abstract class enrol_plugin {
         $enroller = $this->get_enroller($instance->id);
         $admin = get_admin();
 
-        // Some nasty hackery to get strings and dates localised for target user.
+        $oldforcelang = force_current_language($enroller->lang);
-        $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
-        if (get_string_manager()->translation_exists($enroller->lang, false)) {
-            $SESSION->lang = $enroller->lang;
-            moodle_setlocale();
-        }
 
         foreach($users as $key=>$info) {
             $users[$key] = '* '.$info['fullname'].' - '.userdate($info['timeend'], '', $enroller->timezone);
@@ -2258,10 +2245,7 @@ abstract class enrol_plugin {
             $trace->output("error notifying user $enroller->id about all expiring $name enrolments in course $instance->courseid", 1);
         }
 
-        if ($SESSION->lang !== $sessionlang) {
+        force_current_language($oldforcelang);
-            $SESSION->lang = $sessionlang;
-            moodle_setlocale();
-        }
     }
 
     /**

lib/moodlelib.php

@@ -4856,6 +4856,7 @@ function set_login_session_preferences() {
     $SESSION->justloggedin = true;
 
     unset($SESSION->lang);
+    unset($SESSION->forcelang);
     unset($SESSION->load_navigation_admin);
 }
 
@@ -6623,7 +6624,14 @@ function clean_filename($string) {
 function current_language() {
     global $CFG, $USER, $SESSION, $COURSE;
 
-    if (!empty($COURSE->id) and $COURSE->id != SITEID and !empty($COURSE->lang)) {
+    if (!empty($SESSION->forcelang)) {
+        // Allows overriding course-forced language (useful for admins to check
+        // issues in courses whose language they don't understand).
+        // Also used by some code to temporarily get language-related information in a
+        // specific language (see force_current_language()).
+        $return = $SESSION->forcelang;
+
+    } else if (!empty($COURSE->id) and $COURSE->id != SITEID and !empty($COURSE->lang)) {
         // Course language can override all other settings for this page.
         $return = $COURSE->lang;
 
@@ -6655,14 +6663,10 @@ function current_language() {
  * @return string
  */
 function get_parent_language($lang=null) {
-    global $COURSE, $SESSION;
 
     // Let's hack around the current language.
     if (!empty($lang)) {
-        $oldcourselang  = empty($COURSE->lang) ? '' : $COURSE->lang;
+        $oldforcelang = force_current_language($lang);
-        $oldsessionlang = empty($SESSION->lang) ? '' : $SESSION->lang;
-        $COURSE->lang  = '';
-        $SESSION->lang = $lang;
     }
 
     $parentlang = get_string('parentlanguage', 'langconfig');
@@ -6672,13 +6676,34 @@ function get_parent_language($lang=null) {
 
     // Let's hack around the current language.
     if (!empty($lang)) {
-        $COURSE->lang  = $oldcourselang;
+        force_current_language($oldforcelang);
-        $SESSION->lang = $oldsessionlang;
     }
 
     return $parentlang;
 }
 
+/**
+ * Force the current language to get strings and dates localised in the given language.
+ *
+ * After calling this function, all strings will be provided in the given language
+ * until this function is called again, or equivalent code is run.
+ *
+ * @param string $language
+ * @return string previous $SESSION->forcelang value
+ */
+function force_current_language($language) {
+    global $SESSION;
+    $sessionforcelang = isset($SESSION->forcelang) ? $SESSION->forcelang : '';
+    if ($language !== $sessionforcelang) {
+        // Seting forcelang to null or an empty string disables it's effect.
+        if (empty($language) || get_string_manager()->translation_exists($language, false)) {
+            $SESSION->forcelang = $language;
+            moodle_setlocale();
+        }
+    }
+    return $sessionforcelang;
+}
+
 /**
  * Returns current string_manager instance.
  *

lib/setup.php

@@ -820,6 +820,21 @@ if (isset($_GET['lang']) and ($lang = optional_param('lang', '', PARAM_SAFEDIR))
 }
 unset($lang);
 
+// PARAM_SAFEDIR used instead of PARAM_LANG because using PARAM_LANG results
+// in an empty string being returned when a non-existant language is specified,
+// which would make it necessary to log out to undo the forcelang setting.
+// With PARAM_SAFEDIR, it's possible to specify ?forcelang=none to drop the forcelang effect.
+if ($forcelang = optional_param('forcelang', '', PARAM_SAFEDIR)) {
+    if (isloggedin()
+        && get_string_manager()->translation_exists($forcelang, false)
+        && has_capability('moodle/site:forcelanguage', context_system::instance())) {
+        $SESSION->forcelang = $forcelang;
+    } else if (isset($SESSION->forcelang)) {
+        unset($SESSION->forcelang);
+    }
+}
+unset($forcelang);
+
 setup_lang_from_browser();
 
 if (empty($CFG->lang)) {

version.php

@@ -29,7 +29,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$version  = 2014022800.00;              // YYYYMMDD      = weekly release date of this DEV branch.
+$version  = 2014022800.01;              // YYYYMMDD      = weekly release date of this DEV branch.
                                         //         RR    = release increments - 00 in DEV branches.
                                         //           .XX = incremental changes.