From 441b8d6e699affd0ca8c30d1b7eef2337f83bf28 Mon Sep 17 00:00:00 2001
From: Andrew Davis <andrew@moodle.com>
Date: Mon, 7 Oct 2013 14:58:58 +0700
Subject: [PATCH] MDL-26170 RSS: fixed RSS cache clearing when items are
 deleted

---
 blog/edit.php         |  1 +
 blog/rsslib.php       | 14 ++++++++++++++
 mod/forum/discuss.php |  4 +---
 mod/forum/lib.php     | 10 ++++++++--
 mod/forum/rsslib.php  | 10 +++++++---
 5 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/blog/edit.php b/blog/edit.php
index 6a182332238..2bae26cb710 100644
--- a/blog/edit.php
+++ b/blog/edit.php
@@ -120,6 +120,7 @@ if ($action === 'delete'){
             print_error('nopermissionstodeleteentry', 'blog');
         } else {
             $entry->delete();
+            blog_rss_delete_file($userid);
             redirect($returnurl);
         }
     } else if (blog_user_can_edit_entry($entry)) {
diff --git a/blog/rsslib.php b/blog/rsslib.php
index 22c9612fd9f..5f81d201d44 100644
--- a/blog/rsslib.php
+++ b/blog/rsslib.php
@@ -330,3 +330,17 @@ function blog_rss_save_file($type, $id, $tagid=0, $contents='') {
     return $status;
 }
 
+/**
+ * Delete the supplied user's cached blog post RSS feed.
+ * Only user blogs are available by RSS.
+ * This doesn't call rss_delete_file() as blog RSS caching uses it's own file structure.
+ *
+ * @param int $userid
+ */
+function blog_rss_delete_file($userid) {
+    $filename = blog_rss_file_name('user', $userid);
+    if (file_exists($filename)) {
+        unlink($filename);
+    }
+}
+
diff --git a/mod/forum/discuss.php b/mod/forum/discuss.php
index c387790549b..28fe7f8ba9c 100644
--- a/mod/forum/discuss.php
+++ b/mod/forum/discuss.php
@@ -94,10 +94,8 @@
         $DB->set_field('forum_read', 'forumid', $forumto->id, array('discussionid' => $discussion->id));
         add_to_log($course->id, 'forum', 'move discussion', "discuss.php?d=$discussion->id", $discussion->id, $cmto->id);
 
-        require_once($CFG->libdir.'/rsslib.php');
-        require_once($CFG->dirroot.'/mod/forum/rsslib.php');
-
         // Delete the RSS files for the 2 forums to force regeneration of the feeds
+        require_once($CFG->dirroot.'/mod/forum/rsslib.php');
         forum_rss_delete_file($forum);
         forum_rss_delete_file($forumto);
 
diff --git a/mod/forum/lib.php b/mod/forum/lib.php
index 00a3bc16413..ede52632c42 100644
--- a/mod/forum/lib.php
+++ b/mod/forum/lib.php
@@ -4516,7 +4516,7 @@ function forum_delete_post($post, $children, $course, $cm, $forum, $skipcompleti
        }
     }
 
-    //delete ratings
+    // Delete ratings.
     require_once($CFG->dirroot.'/rating/lib.php');
     $delopt = new stdClass;
     $delopt->contextid = $context->id;
@@ -4526,11 +4526,17 @@ function forum_delete_post($post, $children, $course, $cm, $forum, $skipcompleti
     $rm = new rating_manager();
     $rm->delete_ratings($delopt);
 
-    //delete attachments
+    // Delete attachments.
     $fs = get_file_storage();
     $fs->delete_area_files($context->id, 'mod_forum', 'attachment', $post->id);
     $fs->delete_area_files($context->id, 'mod_forum', 'post', $post->id);
 
+    // Delete cached RSS feeds.
+    if (!empty($CFG->enablerssfeeds)) {
+        require_once($CFG->dirroot.'/mod/forum/rsslib.php');
+        forum_rss_delete_file($forum);
+    }
+
     if ($DB->delete_records("forum_posts", array("id" => $post->id))) {
 
         forum_tp_delete_read_records(-1, $post->id);
diff --git a/mod/forum/rsslib.php b/mod/forum/rsslib.php
index 4d5900bdc83..a73900719e9 100644
--- a/mod/forum/rsslib.php
+++ b/mod/forum/rsslib.php
@@ -24,6 +24,9 @@
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+/* Include the core RSS lib */
+require_once($CFG->libdir.'/rsslib.php');
+
 /**
  * Returns the path to the cached rss feed contents. Creates/updates the cache if necessary.
  * @param stdClass $context the context
@@ -68,9 +71,10 @@ function forum_rss_get_feed($context, $args) {
         $cachedfilelastmodified = filemtime($cachedfilepath);
     }
     // Used to determine if we need to generate a new RSS feed.
-    $dontrecheckcutoff = time()-60;
-    // If it hasn't been generated we will need to create it, otherwise only update
-    // if there is new stuff to show and it is older than the cut off date set above.
+    $dontrecheckcutoff = time() - 60; // Sixty seconds ago.
+
+    // If it hasn't been generated we need to create it.
+    // Otherwise, if it has been > 60 seconds since we last updated, check for new items.
     if (($cachedfilelastmodified == 0) || (($dontrecheckcutoff > $cachedfilelastmodified) &&
         forum_rss_newstuff($forum, $cm, $cachedfilelastmodified))) {
         // Need to regenerate the cached version.