First steps on converting FeedSub into the pub/sub basis for OStatus communications:

* renamed FeedSub plugin to OStatus
* now setting avatar on subscriptions
* general fixes for subscription
* integrated PuSH hub to handle only user timelines on canonical ID url; sends updates directly
* set $config['feedsub']['nohub'] = true to test w/ foreign feeds that don't have hubs (won't actually receive updates though)
* a few bits of code documentation
* HMAC support for verified distributions (safest if sub setup is on HTTPS)

And a couple core changes:
* minimizing HTML output for exceptions in API requests to aid in debugging
* fix for rel=self link in apitimelineuser when id given

This does not not yet include any of the individual subscription management (Salmon notifications for sub/unsub, etc) nor a nice UI for user subscriptions.
Needs some further cleanup to treat posts as status updates instead of link references.

1 files changed, 270 insertions, 0 deletions

diff --git a/plugins/OStatus/lib/feedmunger.php b/plugins/OStatus/lib/feedmunger.php
new file mode 100644
index 000000000..eeb8d2df3
--- /dev/null
+++ b/plugins/OStatus/lib/feedmunger.php
@@ -0,0 +1,270 @@
+<?php
+/*
+ * StatusNet - the distributed open-source microblogging tool
+ * Copyright (C) 2009, StatusNet, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @package FeedSubPlugin
+ * @maintainer Brion Vibber <brion@status.net>
+ */
+
+if (!defined('STATUSNET') && !defined('LACONICA')) { exit(1); }
+
+class FeedSubPreviewNotice extends Notice
+{
+    protected $fetched = true;
+
+    function __construct($profile)
+    {
+        $this->profile = $profile;
+        $this->profile_id = 0;
+    }
+    
+    function getProfile()
+    {
+        return $this->profile;
+    }
+    
+    function find()
+    {
+        return true;
+    }
+    
+    function fetch()
+    {
+        $got = $this->fetched;
+        $this->fetched = false;
+        return $got;
+    }
+}
+
+class FeedSubPreviewProfile extends Profile
+{
+    function getAvatar($width, $height=null)
+    {
+        return new FeedSubPreviewAvatar($width, $height, $this->avatar);
+    }
+}
+
+class FeedSubPreviewAvatar extends Avatar
+{
+    function __construct($width, $height, $remote)
+    {
+        $this->remoteImage = $remote;
+    }
+
+    function displayUrl() {
+        return $this->remoteImage;
+    }
+}
+
+class FeedMunger
+{
+    /**
+     * @param XML_Feed_Parser $feed
+     */
+    function __construct($feed, $url=null)
+    {
+        $this->feed = $feed;
+        $this->url = $url;
+    }
+    
+    function feedinfo()
+    {
+        $feedinfo = new Feedinfo();
+        $feedinfo->feeduri = $this->url;
+        $feedinfo->homeuri = $this->feed->link;
+        $feedinfo->huburi = $this->getHubLink();
+        return $feedinfo;
+    }
+
+    function getAtomLink($item, $attribs=array())
+    {
+        // XML_Feed_Parser gets confused by multiple <link> elements.
+        $dom = $item->model;
+
+        // Note that RSS feeds would embed an <atom:link> so this should work for both.
+        /// http://code.google.com/p/pubsubhubbub/wiki/RssFeeds
+        // <link rel='hub' href='http://pubsubhubbub.appspot.com/'/>
+        $links = $dom->getElementsByTagNameNS('http://www.w3.org/2005/Atom', 'link');
+        for ($i = 0; $i < $links->length; $i++) {
+            $node = $links->item($i);
+            if ($node->hasAttributes()) {
+                $href = $node->attributes->getNamedItem('href');
+                if ($href) {
+                    $matches = 0;
+                    foreach ($attribs as $name => $val) {
+                        $attrib = $node->attributes->getNamedItem($name);
+                        if ($attrib && $attrib->value == $val) {
+                            $matches++;
+                        }
+                    }
+                    if ($matches == count($attribs)) {
+                        return $href->value;
+                    }
+                }
+            }
+        }
+        return false;
+    }
+
+    function getRssLink($item)
+    {
+        // XML_Feed_Parser gets confused by multiple <link> elements.
+        $dom = $item->model;
+
+        // Note that RSS feeds would embed an <atom:link> so this should work for both.
+        /// http://code.google.com/p/pubsubhubbub/wiki/RssFeeds
+        // <link rel='hub' href='http://pubsubhubbub.appspot.com/'/>
+        $links = $dom->getElementsByTagName('link');
+        for ($i = 0; $i < $links->length; $i++) {
+            $node = $links->item($i);
+            if (!$node->hasAttributes()) {
+                return $node->textContent;
+            }
+        }
+        return false;
+    }
+
+    function getAltLink($item)
+    {
+        // Check for an atom link...
+        $link = $this->getAtomLink($item, array('rel' => 'alternate', 'type' => 'text/html'));
+        if (!$link) {
+            $link = $this->getRssLink($item);
+        }
+        return $link;
+    }
+
+    function getHubLink()
+    {
+        return $this->getAtomLink($this->feed, array('rel' => 'hub'));
+    }
+
+    /**
+     * Get an appropriate avatar image source URL, if available.
+     * @return mixed string or false
+     */
+    function getAvatar()
+    {
+        $logo = $this->feed->logo;
+        if ($logo) {
+            return $logo;
+        }
+        $icon = $this->feed->icon;
+        if ($icon) {
+            return $icon;
+        }
+        return common_path('plugins/OStatus/images/48px-Feed-icon.svg.png');
+    }
+
+    function profile($preview=false)
+    {
+        if ($preview) {
+            $profile = new FeedSubPreviewProfile();
+        } else {
+            $profile = new Profile();
+        }
+        
+        // @todo validate/normalize nick?
+        $profile->nickname   = $this->feed->title;
+        $profile->fullname   = $this->feed->title;
+        $profile->homepage   = $this->getAltLink($this->feed);
+        $profile->bio        = $this->feed->description;
+        $profile->profileurl = $this->getAltLink($this->feed);
+
+        if ($preview) {
+            $profile->avatar = $this->getAvatar();
+        }
+        
+        // @todo tags from categories
+        // @todo lat/lon/location?
+
+        return $profile;
+    }
+
+    function notice($index=1, $preview=false)
+    {
+        $entry = $this->feed->getEntryByOffset($index);
+        if (!$entry) {
+            return null;
+        }
+        
+        if ($preview) {
+            $notice = new FeedSubPreviewNotice($this->profile(true));
+            $notice->id = -1;
+        } else {
+            $notice = new Notice();
+        }
+
+        $link = $this->getAltLink($entry);
+        if (empty($link)) {
+            if (preg_match('!^https?://!', $entry->id)) {
+                $link = $entry->id;
+                common_log(LOG_DEBUG, "No link on entry, using URL from id: $link");
+            }
+        }
+        $notice->uri = $link;
+        $notice->url = $link;
+        $notice->content = $this->noticeFromEntry($entry);
+        $notice->rendered = common_render_content($notice->content, $notice);
+        $notice->created = common_sql_date($entry->updated); // @fixme
+        $notice->is_local = Notice::GATEWAY;
+        $notice->source = 'feed';
+        
+        return $notice;
+    }
+
+    /**
+     * @param XML_Feed_Type $entry
+     * @return string notice text, within post size limit
+     */
+    function noticeFromEntry($entry)
+    {
+        $title = $entry->title;
+        $link = $entry->link;
+        
+        // @todo We can get <category> entries like this:
+        // $cats = $entry->getCategory('category', array(0, true));
+        // but it feels like an awful hack. If it's accessible cleanly,
+        // try adding #hashtags from the categories/tags on a post.
+        
+        // @todo Should we force a language here?
+        $format = _m('New post: "%1$s" %2$s');
+        $title = $entry->title;
+        $link = $this->getAltLink($entry);
+        $out = sprintf($format, $title, $link);
+        
+        // Trim link if needed...
+        $max = Notice::maxContent();
+        if (mb_strlen($out) > $max) {
+            $link = common_shorten_url($link);
+            $out = sprintf($format, $title, $link);
+        }
+
+        // Trim title if needed...
+        if (mb_strlen($out) > $max) {
+            $ellipsis = "\xe2\x80\xa6"; // U+2026 HORIZONTAL ELLIPSIS
+            $used = mb_strlen($out) - mb_strlen($title);
+            $available = $max - $used - mb_strlen($ellipsis);
+            $title = mb_substr($title, 0, $available) . $ellipsis;
+            $out = sprintf($format, $title, $link);
+        }
+        
+        return $out;
+    }
+}