From f02cb7c71800e6a4426b92ce04c4b8f89006b10a Mon Sep 17 00:00:00 2001
From: Brion Vibber <brion@pobox.com>
Date: Wed, 10 Mar 2010 13:39:42 -0800
Subject: Fix for attachment "h bug": posting a shortened link to an
 oembed-able resource that has been previously used in the system would
 incorrectly save "h" as the item's type and title.

---
 classes/File_redirection.php | 51 ++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 47 insertions(+), 4 deletions(-)

(limited to 'classes/File_redirection.php')

diff --git a/classes/File_redirection.php b/classes/File_redirection.php
index 08a6e8d8b..d96979158 100644
--- a/classes/File_redirection.php
+++ b/classes/File_redirection.php
@@ -115,11 +115,45 @@ class File_redirection extends Memcached_DataObject
         return $ret;
     }
 
+    /**
+     * Check if this URL is a redirect and return redir info.
+     * If a File record is present for this URL, it is not considered a redirect.
+     * If a File_redirection record is present for this URL, the recorded target is returned.
+     *
+     * If no File or File_redirect record is present, the URL is hit and any
+     * redirects are followed, up to 10 levels or until a protected URL is
+     * reached.
+     *
+     * @param string $in_url
+     * @return mixed one of:
+     *         string - target URL, if this is a direct link or a known redirect
+     *         array - redirect info if this is an *unknown* redirect:
+     *              associative array with the following elements:
+     *                code: HTTP status code
+     *                redirects: count of redirects followed
+     *                url: URL string of final target
+     *                type (optional): MIME type from Content-Type header
+     *                size (optional): byte size from Content-Length header
+     *                time (optional): timestamp from Last-Modified header
+     */
     function where($in_url) {
         $ret = File_redirection::_redirectWhere_imp($in_url);
         return $ret;
     }
 
+    /**
+     * Shorten a URL with the current user's configured shortening
+     * options, if applicable.
+     *
+     * If it cannot be shortened or the "short" URL is longer than the
+     * original, the original is returned.
+     *
+     * If the referenced item has not been seen before, embedding data
+     * may be saved.
+     *
+     * @param string $long_url
+     * @return string
+     */
     function makeShort($long_url) {
 
         $canon = File_redirection::_canonUrl($long_url);
@@ -141,11 +175,20 @@ class File_redirection extends Memcached_DataObject
             // store it
             $file = File::staticGet('url', $long_url);
             if (empty($file)) {
+                // Check if the target URL is itself a redirect...
                 $redir_data = File_redirection::where($long_url);
-                $file = File::saveNew($redir_data, $long_url);
-                $file_id = $file->id;
-                if (!empty($redir_data['oembed']['json'])) {
-                    File_oembed::saveNew($redir_data['oembed']['json'], $file_id);
+                if (is_array($redir_data)) {
+                    // We haven't seen the target URL before.
+                    // Save file and embedding data about it!
+                    $file = File::saveNew($redir_data, $long_url);
+                    $file_id = $file->id;
+                    if (!empty($redir_data['oembed']['json'])) {
+                        File_oembed::saveNew($redir_data['oembed']['json'], $file_id);
+                    }
+                } else if (is_string($redir_data)) {
+                    // The file is a known redirect target.
+                    $file = File::staticGet('url', $redir_data);
+                    $file_id = $file->id;
                 }
             } else {
                 $file_id = $file->id;
-- 
cgit v1.2.3-54-g00ecf