As many web masters do, we can host our web feeds (or RSS, a more familiar word to you) on a third-party provider. I’ll share the interesting insights that I got during my recent adventure on web feeds. In this post, I supposed that you know something about RSS or ATOM (two most popular formats of web feeds) and want to know more tricks on how they are working. Especially, I will explore the following questions:
- First of all, who produces the RSS documents and where are they?
- How are your RSS recoganized by browsers automatically?
- What does a third-party provider, like Feedburner, do for you exactly?
- If you use a non-popular blogging system, how do you configure your Feedburner feeds?
- The third-party providers often show statistics such as how many subscribers you have. How do they got such number? Is that number accurate?
- Your feeds links look wired. Can you explain them?
During this post, I will use Feedburner as an example. Here is a good video tutorial on how to use Feedburner. I may not be completely accurate. Please correct me if you find anything wrong. Any discussion, suggestion and suspection is welcome.
- Simply saying, your web publishing software produces RSS documents, Feedburner modifies and publishes them on behalf of you. More details:
- Your web publishing software (e.g. WordPress) usually generates RSS documents for you. They are usually on you domain, such as http://youdomain.com/feed (for your posts) and http://youdomain.com/comments/feed (for your comments). These documents dynamically change to include your new posts and new comments. Later, I’ll call them Local RSS documents.
- Feedburner does not generate RSS documents. Rather, Feedburner takes your RSS documents and modifies them, primarily for statistical purpose. That’s why you need to provide your Local RSS document URLs to Feedburner so that they have a base to work on. Feedburner will put the modified copy on their domain, such as http://feeds.feedburner.com/your-feedburner-feed.
- So now you have TWO versions of RSS documents for your posts, one is on the computer which serves your domain, another is on the computer which serves Feedburner.com. Of course, you also have TWO like that for your comments.
- Your may notice that anyone who visits your blog or website can see an icon of RSS. By clicking that icon, visitors can easily subscribe to your posts or comments. How does this happen? The magic is in the header of the HTML document. There are some codes like this:
<link rel="alternate" type="application/rss+xml" title="Subscribe to RSS 2.0" href="http://yourdomain.com/feed" />Basically, they tell the browser that the RSS feed for current web site is at http://yourdomain.com/feed. When a visitor clicks the RSS icon, the browser will go to such URL and show the RSS document to the visitor. Although the document is XML based, many modern browsers have simple interfaces for RSS documents instead of just showing plain XML codes.
- In a sentence, a third-party provider regularly visits your Local RSS documents, modifies them, and publishes to your subscribers. If you do not use a third-party provider, everybody (RSS reader software) checks your domain for new posts and comments. Once you use a third-party provider, everybody checks domain of the third-party for your new posts and comments.
- Pros? You save bandwidth and enjoy their free service on statistics.
- Cons? You have to trust them on performance and reliability.
- Feedbuner provides quick installing solutions for popular blogging systems, such as Blogger, WordPress, Typepad, Myspace. How if you use none of them but still want to use Feedburner? Simply, you need to modify your template and replace the URLs in the RSS links mentioned in answer 2. You should put the URLs that Feedburner generates for you. So the codes in answer 2 should be changed to something like
<link rel="alternate" type="application/rss+xml" title="Subscribe to RSS 2.0" href="http://feeds.feedburner.com/your-feedburner-feed" />Now what? Everybody who visits your website and clicks on the RSS icon will be brought to http://feeds.feedburner.com/your-feedburner-feed INSTEAD OF http://yourdomain.com/feed. What will happend to http://yourdomain.com/feed? It is still there, just hided from your visitors. If a visitor manually types the URL in the address bar, he can still see the Local RSS documents.
- NOTE: Things go more complex when you use the Feedburner Feedsmith plugin in WordPress. The plugin seems redirecting all visits to local RSS documents to the Feedburner feeds. So you may not be able to see the Local RSS documents by typing the URL.
- Now come to the statistical parts. Cookies usually cannot be used to for statistical purpose in RSS documents as they are often used in web pages. So tracking is often done by putting an invisible image in the RSS documents. If you view the source of the RSS documents, you’ll see something like
<img src="http://www.feedburner.com/fb/feed-styles/images/tk.gif?rdm=N65547" width="1" height="1" alt="" border="0">This is the code from Feedburner for tracking and statistical purpose. IP address would be the most important information to determine number of unique subscribers. Since the mapping between unique subscribers and IP addresses is not always one-to-one, the statistics are just approximate.
- Finally, the smart readers may ask: your post feed link is not http://techiecat.catsgarden.net/feed nor http://feeds.feedburner.com/techiecat. What is that? This is the last trick. I use the “MyBrand” service from Feedburner. So my feed link http://feeds.catsgarden.net/Techiecat is actually redirected to http://feeds.feedburner.com/techiecat.
- Pros? If someday Feedburner is down, I can quick redirect http://feeds.catsgarden.net/Techiecat to another third-party provider, or my own web site. My subscribers won’t feel any inconvenience, since the redirecting process is transparent to them.
Finally, finish this long post. Thanks for your patient reading!