Michele Campeotto

One of the services that made me subscribe to FeedBurner when it has been launched, was the ability to splice my Flickr pictures and my del.icio.us bookmarks together with my blog feed. The problem with doing this with FeedBurner is that it is somewhat limited: I can’t splice together arbitrary feeds, just the ones from the supported services.

The easiest solution I could come up with, was using a personal installation of Planet where I’d subscribe my feeds and then take just resulting feed from there, but I never managed to do this, too much grunt work to do on my part: it wasn’t fun.

Then, Yahoo! launched Pipes. Pipes is a very nice service which allows you to play with feeds and munge them together by applying different kinds of filters. Pipes are fun to play with you drag and drop the building blocks, connect them together, add some magic and you have your new feed.

Some days ago, Gina Trapani posted an article on lifehacker explaining how to build your master feed, collecting all the feeds you produce on various blogs and services together in a single feed. She also has an example on how to inspect the feed contents to filter some items from the resulting feed.

In her article, Gina says she’d like to add a prefix for the feed source to differentiate the item titles. Here I have a demonstration of the power of Yahoo!’s new toy: you can do that, by using the Regex operator module to change the contents of an item’s element.

The steps to build a Pipe like this are:

• use a different Fetch source for each of your feeds
• filter the elements you don’t want
• apply the Regex operator to the title to replace ”^” with ”Source:”, which is just Regex-fu for “put the source name in front of the title” (you’ll have to put the actual name you want for the source instead of “Source”, see the example pipe I created). (updated with hint by muczachan)
• put all the resulting feeds in a Union operator
• sort the Union output feed

Optionally, you can limit the number of items in the resulting feed by using the Truncate operator. Also, should you have more feeds than the five input sockets of the Union module provides, you can add more Union modules and then combine them with another one.

Feel free to clone the pipe I created and adapt it to your own feeds.