From 128a00c4ab381417ac4d3be1f72ad16569534708 Mon Sep 17 00:00:00 2001
From: Mikael Nordfeldth <mmn@hethane.se>
Date: Wed, 24 Feb 2016 16:48:44 +0100
Subject: [PATCH] Include feeds in Link HTTP headers, for easier discovery

---
 lib/feed.php               |  5 +++++
 lib/noticestreamaction.php | 12 ++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/lib/feed.php b/lib/feed.php
index e04c69be6c..d61c3e8a34 100644
--- a/lib/feed.php
+++ b/lib/feed.php
@@ -62,6 +62,11 @@ class Feed
         $this->title = $title;
     }
 
+    function getUrl()
+    {
+        return $this->url;
+    }
+
     function mimeType()
     {
         switch ($this->type) {
diff --git a/lib/noticestreamaction.php b/lib/noticestreamaction.php
index fb592915a7..e668a27daf 100644
--- a/lib/noticestreamaction.php
+++ b/lib/noticestreamaction.php
@@ -34,6 +34,18 @@ abstract class NoticestreamAction extends ProfileAction
         // pass by default
     }
 
+    public function extraHeaders()
+    {
+        parent::extraHeaders();
+        foreach ($this->getFeeds() as $feed) {
+            header('Link: <'.htmlspecialchars($feed->getUrl()).'>;' .
+                        ' rel="'.htmlspecialchars($feed->rel()).'";' .
+                        ' type="'.htmlspecialchars($feed->mimeType()).'"',
+                    false    // don't overwrite previous headers of this sort
+                    );
+        }
+    }
+
     // this fetches the NoticeStream
     abstract public function getStream();
 }