Thursday, October 22, 2009

An Amazon Affiliate Tutorial

Ok, so I'm a little behind the times. Amazon's Affiliate Program has been around for a while--since 1996 to be exact. Everyone and their grandma must have an account by now, making millions off sales of "The Secret" that they linked to on their blog (this is actually the secret that the book talks about). But incase you happen to be Amish, here's a short tutorial on the whole process of signing up for an account and building affiliate links.

1. Visit and click the "Join now for FREE!" button. It requires that you create an Amazon account first if you don't already have one.

2. It then asks you for your contact information and has some questions about the website/blog where you'll be putting your affiliate links.

3. And that's all the information they need to get your account set up. You don't even have to submit your payment information (although, you'll want to do this eventually...after all, making a few bucks is why you're here, right?). As you can see in the screenshot, Amazon assigns you a unique "Associates ID". This important identifier will be stuffed into all the affiliate URLs you create so that Amazon knows who give money to when a sale is made. To start making links, click the "Learn More" link in the "Product Links" box.

4. It's really easy to create affiliate links. It just takes a few clicks of the mouse and some copy and pasting. First, search for the product you want to link to. I chose a book I recently read.

5. Next, find the product in the search results and click the "Get Link" button.

6. This will take you to the page that lets you build your link. There's a lot of options here you can play with, so take some time to explore this page on your own. Once you're done crafting the link to your liking, copy the HTML code in the "step 3" box and paste it on your site. It's no secret--it's that simple!

Tuesday, October 6, 2009

Using Magpie to parse Blogger feeds

I recently redesigned my website and one thing I changed was putting my blog on the front page instead of just linking to it. But what's cool (at least, according to my own geeky tastes) is that my blog is hosted on Blogger--not on my website! In this post, I'm going to walk through how I did this.

1. Blogger setup
First, you need to make sure your Blogger feeds are configured to include the full content of each blog post (as opposed to just the first paragraph or whatever). I think this is the default setting, but to make sure, to go the Settings page and click on the "Site Feed" tab. The "Allow Blog Feeds" option should be set to "Full".

2. Atom feed URL
Now, you must get the URL of your blog's Atom feed. Go to your blog's homepage and view the source (in Firefox, this is under "View > Page Source"). Look for a "link" tag that looks like the one below, and grab the value of its "href" attribute.
<link rel="alternate" type="application/atom+xml" title="mangstacular - Atom" href="" />

Note: In this tutorial, I use the Atom feed. The RSS feed also has all the same information--it's just arranged differently.

3. Magpie setup
Download Magpie. This is a wonderfully easy-to-use RSS/Atom parser written in PHP which we'll use to parse the Atom feed.

You'll want to configure Magpie to cache the Atom feed so that it only downloads it when your blog changes in some way (i.e. when there's a new post or a new comment). This way, your website won't have to download the feed from Blogger every time someone visits your page. Open the "" file and add these two lines somewhere at the top:
define('MAGPIE_CACHE_ON', true);
define('MAGPIE_CACHE_DIR', 'cache');

This will turn on caching and instruct Magpie to save the cached Atom file in the directory you specify.

Note: Be sure that the permissions of the cache directory allow your web server to write to it. The way you do this varies from server to server, based on the user that your PHP process runs under, but here are the commands that I had to run:
chmod 775 cache
chgrp web cache

What you do NOT want to do is set the folder to be globally writable. While this would work, it would also allow anyone on the Internet to write to that directory--not a good thing.

4. Parse the Feed
Now you're ready to write the code that fetches and parses the feed. Simply calling Magpie's "fetch_rss" function will parse the feed and return all the data in an associative array (despite "rss" being in the function name, it will also parse Atom feeds). No need to deal with any XML. Below is some sample code.

Note: There are a couple quirks, which may be Blogger-specific--be sure to read the code comments.


$atom = fetch_rss('');
foreach ($atom->items as $item){
//var_dump($item); //see all the stuff that's in each item

$date = date('F j, Y', strtotime($item['published']));
$title = $item['title'];
$content = $item['atom_content']; //no need to run html_entity_decode() or anything
$url = $item['link'];

//because there are two <link> tags whose "rel" attributes are the same...
// stuffs the "href" attributes from both tags into this one string...
// you must extract the URL you want...
//...which in my case is the URL to the comments page
$commentsUrl = substr($item['link_replies'], strpos($item['link_replies'], 'https'));

$numberOfComments = $item['thr']['total'];

//generate HTML for the entry

And now it looks like you're running fancy Wordpress software! ;)