A month ago there would have been no reason to write this post, because Google Reader made it’s own RSS feed of the posts you wanted to share. See, Google wants to drive people to use Google+, and they seem to be doing this by crippling their other services that have even a smidgen of social usefulness. The thing is, I liked the social bits of Google Reader. Sure, they were a bit of an afterthought, and mildly dysfunctional, but I got a lot of value from reading what other people shared, and I liked that when I shared something I was creating a kind of archive of stuff I liked on Reader, with an RSS feed of its very own.

The great thing about RSS is that it can be consumed by arbitrary 3rd party applications. The likes of Google, Facebook and Twitter don’t like this, because they want control over the 3rd parties that can access their stream. So they are quite prepared to kill off RSS services in their applications, because it does not serve their mission. You can no longer get an RSS feed of your Twitter stream (as far as I know), there is no RSS built into Google+ (which I have yet to have the time to fully grok).

My needs are small, I want an RSS feed of the stuff I want to share from Google Reader, so that other people can follow the things I share in Reader (if they want), and I can pipe that information elsewhere (I use dlvr.it to post selected RSS feeds into Twitter). Google doesn’t want to provide that anymore, so I’ll hack something together.

The ingredients:

1. These simple instructions for how to render an RSS feed from a MySQL backend.
2. The instructions for how to create your own “Send to:” item in Google Reader
3. My rudimentary PHP hackery skills

The code:
All source is available on BitBucket.

First, we need a database connection. The database is set up exactly as described in (1), above.

<?php
DEFINE('DB_USER', 'db_user');
DEFINE('DB_PASSWORD', 'db_password');
DEFINE('DB_HOST', 'localhost');
DEFINE('DB_NAME', 'db_name');
// Make the connnection and then select the database.
$dbc = @mysql_connect(DB_HOST, DB_USER, DB_PASSWORD) OR die(mysql_error());
mysql_select_db(DB_NAME) OR die(mysql_error());
?>

Now, when the page is visited, we want to render what is in the database as an RSS feed (again, this is a simple adaptation of the code in (1)):

<?php
  class RSS {
        public function RSS() {
                require_once ('mysql_connect.php');
        }
        public function GetFeed() {
                return $this->getDetails() . $this->getItems();
        }
        private function dbConnect() {
                DEFINE('LINK', mysql_connect(DB_HOST, DB_USER, DB_PASSWORD));
        }
        private function getDetails() {
                //header of the RSS feed
                $detailsTable = "webref_rss_details";
                $this->dbConnect($detailsTable);
                $query = "SELECT * FROM ". $detailsTable;
                $result = mysql_db_query (DB_NAME, $query, LINK);
                while($row = mysql_fetch_array($result)) {
                        //fairly minimal description of the feed
                        $details = '<?xml version="1.0" encoding="ISO-8859-1" ?>
                                <rss version="2.0">
                                        <channel>
                                                <title>'. $row['title'] .'</title>
                                                <link>'. $row['link'] .'</link>
                                                <description>'. $row['description'] .'</description>
                                                <language>'. $row['language'] .'</language>
                                                ';
                }
                return $details;
        }

        private function getItems() {
                //return all the items foe the RSS feed
                $itemsTable = "webref_rss_items";
                $this->dbConnect($itemsTable);
                $query = "SELECT * FROM ". $itemsTable;
                $result = mysql_db_query(DB_NAME, $query, LINK);
                $items = '';
                while($row = mysql_fetch_array($result)) {
                        $items .= '<item>
                                <title>'. $row["title"] .'</title>
                                <link>'. $row["link"] .'</link>
                                <description><![CDATA['. $row["description"] .']]></description>
                        </item>';
                }
                //close the feed
                $items .= '</channel>
                                </rss>';
                return $items;
        }
}
?>

Finally, we need a method for adding new stuff for the feed. This code takes the GET variables passed to it by Google Reader, and stores them in the DB:

<?php
if ($_GET['url']) {
        //receive google reader 'send to' items, and store in mysqldb
        $url = $_GET['url'];
        $source = $_GET['source'];
        $title = $_GET['title'];
        $simple_check = $_GET['check'];
        //stops anyone adding new items to your feed unless they have the key
        if ($simple_check == 'uniquepasscodehere') {
                //statement adds new item to RSS database
                $insert_statement = "INSERT INTO webref_rss_items(title, description, link) VALUES('$title', '$source', '$url')";
                require_once('mysql_connect.php');
                $result = mysql_query($insert_statement, $dbc);
                if ($result) {
                        echo "<p>Success!";
                        //would be nice to close the window automatically after a couple of seconds
                }
                else {
                        die('<p>Invalid query: ' . mysql_error());
                }
        }
}
else {
        //render everything in the db as RSS
        header("Content-Type: application/xml; charset=ISO-8859-1");
        include("RSS.class.php");
        $rss = new RSS();
        echo $rss->GetFeed();
}
?>

Now, I can set up the Send To: item in Google Reader:

Finally, click ‘Send To: -> Readershare’ in the footer of an item in Google Reader, and it is rendered into my RSS feed, which can then be consumed by other applications, including Google Reader itself (so if you want to subscribe to my Google Reader shared items feed, you can find it at http://fuzzierlogic.com/readershare). Oh, and I can pipe my Google Reader shares back into Twitter again.