The most funny part of knowing XMPP protocol is that you can execute all your daily web needs using it. Be it playing anagram online or achieving your status messages. And your life gets easy if you are using an XMPP Client Library like JAXL.

Here I have tried to create a simple bot which allows you to read newest links posted on dzone category wise. Simply add [email protected] in your gtalk messenger and start by typing options.

Available options are:

• frontpage: Will send you latest links on frontpage.
• queue: Will send you latest links in queue.
• tag: Send in a tag e.g. php,java,xml and you will get latest links for the particular tag

Here is modified eventMessage() method of JAXL library powering [email protected]:

    function eventMessage($fromJid, $content, $offline = FALSE) {

      // If the message is not an offliner
      if(!$offline) {
        if($this->restrictJid && !in_array($this->getBareJid($fromJid),$this->authorizedJid)) { // Block un-authorized users
          $this->logger->logger($fromJid." tried using this service by sending:n".$content);
          $message = 'You are not authorized to use this service';
          $this->sendMessage($fromJid,$message);
          return TRUE;
        }
        else {
          $content = strtolower(trim($content));

          // Build RSS Feed URL depending upon passed IM
          if($content == "options") {
            $message = "Available options are:n";
            $message .= "*1. frontpage:* Will send you latest links on frontpage.n";
            $message .= "*2. queue:* Will send you latest links in queue.n";
            $message .= "*3. tag:* Send in a tag e.g. php,java,xml and you will get latest links for the particular tagn";
            $this->sendMessage($fromJid,$message);
            return TRUE;
          }
          else if($content == "frontpage") $url = "http://www.dzone.com/links/feed/frontpage/rss.xml";
          else if($content == "queue") $url = "http://www.dzone.com/links/feed/queue/rss.xml";
          else $url = "http://www.dzone.com/links/feed/frontpage/".$content."/rss.xml";

          // Generate cache file location
          $cache_file = "cache/dzone/".md5($url)."-".$content.".rss";

          // If cache file is not older than 900 seconds (15 min)
          if(file_exists($cache_file) && (filemtime($cache_file) > time() - 900)) {
            $this->logger->logger("RSS already found cached...");
          }
          else { // else fetch a fresh copy of RSS
            $this->logger->logger("Fetching RSS for url:n".$url);
            $head = $this->fetchWebURL($url);
            if($head['errno'] == 0 && $head['http_code'] == 200) {
              $this->logger->logger("Fetched successfully...");
              $data = $head['content'];
              $fh = fopen($cache_file,"w");
              fwrite($fh,$data);
              fclose($fh);
            }
            else {
              // Send a message saying no such feed exists
              $this->logger->logger("Failed to fetch the RSS feed...");
              $message = 'No feed exists for the passed keyword: '.$content;
              $this->sendMessage($fromJid,$message);
              return TRUE;
            }
          }

          // Parse RSS Feed
          $r = &new XML_RSS($cache_file);
          $r->parse();
          $NumberOfFeeds = count($r->getItems());
          if($NumberOfFeeds > 0) {
            $message = '';
            foreach($r->getItems() as $key => $item) {
              if($this->count < $this->maxResults) {
                $message .= "*".$item["title"]."*n";
                $message .= $item["link"]."n";
                $message .= $item["description"]."nn";
                $this->count++;
              }
              else {
                break;
              }
            }
            $message .= "powered by *Jaxl* http://code.google.com/p/jaxl"."nn";
            $this->sendMessage($fromJid,$message);
            $this->count = 0;
            return TRUE;
          }
          else {
            // Send a message saying no feed found
            $message = 'No feed was found for passed keyword: '.$content;
            $this->sendMessage($fromJid,$message);
            return TRUE;
          }
        }
      }
      else {
        // Send an appropriate message
        $this->logger->logger($fromJid." sent an offliner saying:n".$content);
        return TRUE;
      }
    }

To run this sample application you need:

• JAXL Library (http://code.google.com/p/jaxl)
• XML_RSS Package (pear install XML_RSS)
• Create a directory cache/dzone where this application will cache all rss files
• Include jaxl4dzone.class.php in index.php, instead of jaxl.class.php and run ‘php index.php’ from command line to start this application

Checkout the complete code and JAXL library from http://code.google.com/p/jaxl.

Now browse new links even when dzone is down for maintenance 😛
Do let me know about your feedbacks 🙂