Blogging Roller

WIP #6: Feed-based Integration

2012-10-08T10:38:43+00:00

This is the sixth in my series of Web Integration Patterns. Check out the intro at this URL http://rollerweblogger.org/roller/entry/web_integration_patterns

Synopsys

This pattern is about integrating web sites and applications by using standard feed formats to convey timely information, updates, status messages, events and other things from one web application to another.

Motivations

Take advantage of the many tools and services that can produce, consume, aggregate and build work-flows around feeds as a way to integrate web applications.
Use a standards-based approach to ensure that that widest range of feed producers and consumers can be supported. Make it so everybody who needs can read your feeds.

Related Patterns

Search Integration
Web APIs

A feed is a list of entries, each with an timestamp, ID, title, content and metadata like categories and tags. Entries are arranged in reverse chronological order. The entries in a feed can represent just about anything from blog entries, Flickr photos, YouTube videos, source-code change sets or tasks in a change management system. A feed is an XML resource that is available at a URL. If you want updates, then you poll that URL, ideally using HTTP Conditional GET so that you only pull down the feed when it has been updated.

Generally speaking there are two standard feed formats in use on the web: RSS and Atom, both are based on XML. Both use different element names, for example: what Atom calls "entries" RSS calls "items." Because these standard formats are so widely supported, providing a feed is an effective way to share updates from your web site or application.

Elements of Atom (from my 2006 presentation on Atom)

Another flavor of feeds is ActivityStrea.ms, which is essentially a feed format with a schema for representing about 70 different types of activities. These activities can be social network activities like share or friend and they can also be business activities like assign, resolve or schedule. One advantage of using the ActivityStrea.ms standard is that it has both an Atom and a JSON mapping.

Producing Feeds

Feed-based Integration is listed as a basic pattern because it can be very easy to implement. The ability to produce feeds is built-in to many different types of web applications from blog and wikis to continuous integration servers. If you are writing your own web application, you can choose to use XML tools to produce your feeds, a templating engine or a dedicated feed toolkit like ROME. You’ll find plenty of XML tools and templating engines no matter what language you are using.

Which type of feed should you produce? That depends. Atom is the most complete specification and is a true IETF standard, so often it is the right choice. To make the right decision, you have to consider who is going to be consuming your feeds. If your consumers prefer RSS, them give them that. If your consumers prefer JSON over XML, then consider ActivityStrea.ms in JSON flavor.

Consuming Feeds

You can use a wide variety of tools to parse and process feed data. For example, there are many web sites and services that can digest feeds and trigger other events and processing. Services such as Yahoo Pipes and If This Then That can read feeds, process each item and perform other actions based on item values.

Processing a feed with Yahoo Pipes (from Marsh Gardiner's post)

You’ll also find a variety of JavaScript widgets that can parse and display feeds in a website. Most web portal and software with a web dashboard features will include a component that can display feeds. And, of course, you can use a reader that supports RSS/Atom feeds, such as Google Reader or Feedly or FlipBoard, to monitor and read feeds.

If you need to add RSS/Atom reading features to your own software, you can use standard XML parsing tools and, for most language, you’ll find that there are open source libraries specifically designed for parsing feeds.

For more information in producing and consuming feeds, RSS and Atom in Action. Also, you might find my presentation on Beyond Blogging: Atom Format and Protocol useful.

Beyond the basics

Feeds are a great way to do simple integrations, but there are limitations and there will be times you’ll need to go beyond the basics with RSS and Atom feeds. Here's an example. Normally, with feeds, clients have to repeatedly poll the feed URL for updates. This is annoying, and inefficient, even with HTTP Conditional GET. To address this problem, you can setup a PubSubHubub server that will subscribe to feeds and will then notify other subscribers instantly when updates are available, so that those other subscribers don’t have to poll.

Another problem is that, if you don’t poll often enough, you might miss some updates and they may “scroll” off the bottom of the feed before you see them. Feed providers can address this problem by supporting Feed Paging and Archiving, which allows clients to use next and previous links to “page” back to feed items that are no longer in the first page of the feed.

One more beyond-the-basics item to mention is the related pattern Web APIs, which we'll cover later. Web APIs are listed as a related pattern to Feed-based Integration. That's because feeds have been used as the basis for several "Web APIs" or protocols. These protocols specify how to use HTTP POST, GET, PUT and DELETE and create, retrieve, update and delete web resources that are represented as feed entries. Examples are the IETF's Atom Protocol, Microsoft's OData and Google's GData APIs.

That’s it for Feed-based Integration. In my next posts, we'll move in to the Advanced Patterns.

Month of blogging

2009-08-02T16:04:33+00:00

Crammed into one post...

After a month of blog neglect, the automatic Latest Links posts from my Delicious.com account started to pile up in my blog editor. Back in the glory days of this blog, I blogged about things instead just saving links or tweeting about them and would never have let a month go by without blogging. I realized that, by adding some commentary/opinion for each, I could turn a month's worth of links into a month's worth of blog posts and thus gain total absolution for my sin of going a full month without a post. So that's what I did.

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Category: Blogging

Joe Gregorio: Comment system review
"Comparing Disqus, IntenseDebate and Google Friend Connect." Joe Gregorio looked at commenting systems and ended up chosing Intense Debate.
Integrating Disqus and Roller Weblogger on blogs.sun.com
"I've recently updated my site to use Disqus the blog comment hosting and conversation site." Sun UK CTO Wayne Horkan explains how (and why) to use the Disqus in a Roller, with code and helpful comments from Disqus CEO Daniel Ha.
Official Google Blog: New Blog Search tools
"Feeds, Hot Queries and Latest Posts." Nice to see Google is still working on blog search despite the rumored death of blogging.

Category: Feeds

pubsubhubbub - Google Code
"A simple, open, server-to-server web-hook-based pubsub (publish/subscribe) protocol as an extension to Atom." Collaboration between Google and SixApart folks to allow quick notifiation of new content to feed subscribers and reduce load on feed publishers. Hub implementations are underway for AppEngine/Python, Erlang, Python and Ruby. Hmm... no Java?

Category: General

The Ryding List | Why Not?
"I have found a wealth of great things to do in Raleigh." Great list of things to do around Raleigh by newcomer John Ryding, one of my coworkers at IBM.
The Different CTO Roles - All Things Distributed
"there is no well established definition of what a CTO actually does." Of special interest to me now that I work on a CTO's staff.
Life During Wartime video from Stop Making Sense - Boing Boing
"This is the best concert movie I've ever seen." Me too.

Category: IBM

Integrating and Extending Rational Team Concert 2.0
Great guide and presentation on Team Concert development via the Jazz Server SDK. Referring to this a lot these days.
Eclipse Galileo for Mac: Cocoa or Carbon?
"Carbon is more mature and thoroughly tested, the new Cocoa implementation offers advantages and improvements." And the answer is: 32-bit Cocoa. Yep, I'm paying attention to Eclipse again. It's really the only way to do Jazz development.
Whitepaper: e4 Technical Overview
Lots of detail on the apparently massive changes coming in Eclipse e4 including the ability write Eclipse components in JavaScript and to run "existing SWT applications to be executed on web platforms such as ActionScript/Flash."

Category: Java

James Strachan: Scala as the long term replacement for Java
"if someone had shown me the Programming Scala book back in 2003 I'd probably have never created Groovy." I'm sure that sent a lot of folks to Amazon, including me.
Google App Engine plugin in NetBeans
"With a video showing how easy it is to develop Google App Engine application in NetBeans. You can see that Hello World takes just 1 minute. :-)" Looks good and apparently it's an open source side-project. Hosted at Kenai.
Trails of EasyExtend: Java Spring - or the Biggus Dickus effect
"Looking at the API alone Spring feels like reading a parody on Java enterprise software." Schadenfreude for me; never been a fan and always thought of it as a big grab bag of insidious crap I don't need.

Category: Open Source

NYTimes.com: For Mozilla and Google, Group Hugs Are Getting Tricky
"Google pays Mozilla hefty fees in return. The deal accounted for 88 percent of Mozilla's $75 million in revenue in 2007." Makes you wonder about the future of Firefox, Thunderbird, etc.
Official Google Blog: Introducing the Google Chrome OS
"The software architecture is simple: Google Chrome running within a new windowing system on top of a Linux kernel." Yet another Linux distro. That's cool with me; I like Linux distros.
The Java Wars, continued (Scripting News)
"most people want XP on their netbook, not Linux. That was true yesterday and it's still true today." Dave Winer's take on Google's Chrome OS. I think he's probably right at the moment but things are changing rapidly.

Category: Social Software

Creating a Google Data Gadget - Google Data APIs - Google Code
"This article will walk you through creating a Blogger gadget." Google and OpenSocial Gadget support for OAuth makes things easier, but it's still a PITA.
Writing OAuth Gadgets - Gadgets API - Google Code
"send mail to oauthproxyreg@google.com with the following information to register your OAuth Consumer Secret." If you want to write a Gadget that uses OAuth to access Twitter there's an icky manual registration step involved. Apparently the solution to this problem is for Twitter.com to enhance their "OAuth configuration to accept digital signatures directly from iGoogle."

Category: Sun

The end of Sun
"And that is why Schwartz isn't here, I believe. Because he genuinely loved Sun and its employees." A depressing article for former Sun employee to read, or anybody I guess. I do think there is something to this quote about Scwhartz.
Oracle-Sun Creating Churn - Forbes.com
"Suns loyal customers are defecting in droves." Not really very surprising considering the conventional wisdom, which seems to be that Oracle will gut Sun's software efforts and ditch the hardware entirely.
Computerworld Blogs: Is Oracle getting ready to kill OpenSolaris? -
"Sun, Oracle and third-party sources are telling me that OpenSolaris developers are afraid." This article is typical of what I've seen from the author: dumb speculation of the mean-spirited variety.
Justice department extends Oracle-Sun probe
"All that's left is one narrow issue about the way rights to Java are licensed." I don't there's a chance in hell that it is, but wouldn't it be fun if this was all about the Sun-Apache Terms of Use controversy?

Web development

InfoQ: Twitter, an Evolving Architecture
Brief overview of Twitter architecture, use of caching and message queue technologies.
Evaluation of Javascript Libraries
"jQuery and YUI come out on top, Prototype at the bottom." Helped convince me that, now that we have YUI, we don't really need Prototype and Scriptaculous in Roller.
"MooTools vs JQuery vs Prototype vs YUI vs Dojo revised
"Prototype is among the slowest." More justification for ripping out Prototype and Scriptaculous.

And now, back to your regular schedule of blogging, or not.

Atom news: Apache Abdera graduates

2008-11-21T15:54:48+00:00

Congratulations to the Apache Abdera team, who've just graduated to full Apache top level project status. The don't have the new site at abdera.apache.org up yet and they're still not quite at 1.0 yet, but this is a major milestone. They've got the best Atom format and protocol toolkit around, in my opinion.

via Garett and James.

My A list

2008-03-25T11:34:33+00:00

Here's a concept that I've been using to help me both in my blog writing and to filter all the incoming feeds, tweets, photo sharing and social bookmarking items that come in via my feed reader: my A list. It's not made up of famous folks and big blog names like Scoble or Winer or Arrington. My A list is made up of people that I know or work with and that I believe are following me in some way, reading my blog, subscribing to my tweets or working with me on a project. I've got a folder in my feed reader and my A list is always the one I read first. Sometimes I don't get much farther than than before hitting the mark all read button. And when I do blog, that folder helps remind my of who I'm writing for. "A" stands for audience.

Yahoo Weather RSS module for ROME

2008-01-23T15:40:22+00:00

Apparently, I spoke to soon about ROME being in maintenance mode. There's an all-new Yahoo Weather module for ROME from Robert "kerbernet" Cooper.

ROME vs. Abdera

2008-01-22T18:18:40+00:00

For Java developers starting out with RSS and Atom, here are some notes to help you figure out the differences between the Java.net ROME and Apache Abdera (incubating) projects.

ROME is a set of Java tools for parsing, fetching and generating all forms of RSS and Atom feeds. The core ROME library is relatively small and depends only on the somewhat creaky old JDOM XML parser. Available separately are modules to support various feed extensions such as OpenSearch, iTunes, GeoRSS, etc. ROME was originally developed and open sourced by Sun Portal dev team members in 2004.

ROME Propono is a subproject of ROME that supports publishing/editing entries and files to blog servers and AtomPub servers. Propono is made up of three parts: 1) a Blog Client library can publish via either the old lagacy MetaWeblog API or the shiny new AtomPub protocol, 2) an AtomPub client that publishes only via AtomPub and 3) a framework for creating AtomPub servers. Propono was developed by Ramesh Mandava and Dave Johnson, based on code from RSS and Atom in Action and open sourced as part of the Sun Web Developer Pack in 2007.

Abdera is a set of Java tools for working with Atom feeds and AtomPub protocol. This includes a parser, writers, an AtomPub client and a framework for creating AtomPub servers. Abdera's Atom feed parser uses STAX, so it uses less memory and is faster than ROME. Abdera's Atom feed support is more comprehensive than ROME's and it supports signatures, encryption, Atom to JSON, extensions for Threading, Paging, GeoRSS, OpenSearch, GoogleLogin, etc. etc. Abdera was developed by IBM and contribued to Apache in 2006.

Now let's compare frameworks. The pros and cons of ROME are:

Pro: complete RSS support, all of the dozen various flavors
Pro: it's generally simple and small, depending only one jar (JDOM)
Pro: easy to understand and use the AtomPub server framework
Pro: MetaWeblog API support
Con: Atom feed support not as comprehensive as Abdera
Con: parser uses lots of memory, slower, JDOM based
Con: community not as active, seems to be in maintenance mode (See also Ohloh stats)

The pros and cons of Abdera are:

Pro: comprehensive Atom feed support, lots more Atom extensions
Pro: faster more efficient parser
Pro: In the Apache Incubator with active and growing community (See also Ohloh stats)
Con: lots of dependencies
Con: AtomPub server framework poorly documented, overly complex (rewrite coming soon)
Con: no RSS support (there is something in Abdera contrib, but it's incomplete).

There you have it. ROME and Abdera folks: think that's a fair comparison? Are you a ROME or Abdera user? How would you like to see these frameworks move forward?

Happy New Year 2008

2008-01-01T23:54:24+00:00

Happy New Year to all the readers of this blog and all the folks who happen to have arrived here via one of the various planets, spam blogs and Google search result pages that include it. I hope you all have a prosperous and pleasant year ahead. I'm hoping for the same. It's nice to start the new year with some good news and I've got some; check this out:

RSS and Atom in Action has been out for over a year now and just as the phenomenal sales are starting to drop off, something wonderful has happened. The book has been nominated for the prestigious Stephen T. Colbert Award for Literary Excellence. As you can see in the photo above, at least one copy of the book is already carrying the Colbert nominee seal. Avoid the rush and buy your copy of RSS and Atom in Action now.

Those who have read Colbert's I Am America (And So Can You!) will understand the significance of this important award and understand the impact on future sales of the book. To learn more about the nomination process and criteria, buy yourself a copy of Colbert's book and then flip to page 214½. Cheers!

RSS best practices doc published

2007-10-16T22:16:42+00:00

RSS advistory board: The RSS Profile makes it easier for feed publishers and programmers to implement RSS 2.0, offering advice on issues that arise as you develop software that employs the format. For 18 months, the board worked with the RSS community on interoperability issues, receiving help from representatives at Bloglines, FeedBurner, Google, Microsoft, Netscape, Six Apart and Yahoo. The profile tackles the most frequently asked questions posed by developers:

How many enclosures can an item contain?

Are relative URLs OK in item descriptions?

Is it OK to use HTML in elements other than an item's description?

For the answers, read the sections on enclosures, item descriptions and character data, respectively. Sam Ruby announced this morning that the Feed Validator now tests for conformance to the profile, offering 11 new checks for improving interoperability.

Kudos to the RSS Advistory Board. The RSS Profile is an excellent guide to publishing RSS. Plus, it's very nice to see the confusing parts of RSS clarified and to see those clarifications linked to from the RSS spec.

Windows Live Writer + AtomPub

2007-10-16T09:32:34+00:00

Joe Cheng: Iâ€™m starting a (hopefully short) series of blog posts documenting the specifics of how the upcoming AtomPub-enabled release of Windows Live Writer will behave, and what AtomPub-enabled blog* servers can do to ensure the best interop with us. I also hope other blog client implementers can learn from our experience and consider using the same rules and behaviors we do when implementing their own AtomPub support.

Very nice. I'll be watching this one closely, looking for ways to improve Roller's and ROME's AtomPub support.

Latest links: AtomPub news round-up edition

2007-10-12T12:31:13+00:00

I've been in crunch-mode working on a new project, but I've been trying to keep an eye on what's going on the world of Atom Publishing Protocol or AtomPub as the cool kids call it. Here's a wrap-up of some of the AtomPub news I've picked up on the past month or so.

Specifications

The big news is, of course, that AtomPub has been granted an RFC number RFC-5023 and is now an IETF "proposed standard" like Atom format (RFC-4287). The folks at Ricoh have provided a Japanese translation.

Extensions to AtomPub are under development and you can find a good list of them at the XML Cover Pages page for Atom. One I find interesting is James Snell's AtomPub Feature Discovery spec, which is designed to help AtomPub clients determine what features are supported and required by servers. The features spec is controversial and has sparked a lot of good discussion including, Brian Smith's email Atom Weblog Publishers Guide and Sergey Beryozkin and Dan Diephouse's discussion of AtomPub and WS-Policy

Server implementations

More big news to report here: the new Wordpress 2.3 release provides full support for AtomPub. Sam Ruby blogged about it in Wordpress 2.3 loves AtomPub and the Wordpress 2.3 AtomPub docs provide a good summary and cover some limitations. Yesterday, Sam posted Wordpress vigilance and plans. He wants to get Wordpress to score a perfect 0 errors and 0 warnings on the APE tests, which means among other things preserving foreign markup.

New releases of Apache Roller have also been updated for the final AtomPub spec. The upcoming Roller 3.1.1 and Roller 4.0 releases include AtomPub support. Both releases are up for vote now, so they should be out Real Soon Now. And I'm working on adding AtomPub support for comments for Roller 4.1, building on top of the Atom Threading Extension (RFC-4685).

I've been googling and browsing the SixApart site, but I can't figure out if Movable Type 4.0 supports the final AtomPub spec. Anybody know?

And Google has added another AtomPub based API. Read about it on Bill de hÃ“ra's blog YouTube via GData and on the YouTube Developer API blog: New YouTube API Released into the Wild.

Client implementations

In Stick a fork in it Joe Cheng writes "The Windows Live Writer team is still on track to deliver AtomPub support in the next version, which I am looking forward to immensely. Itâ€™s definitely an exciting time to be in the blogging tools space!" Based on what I saw at the last face-to-face AtomPub interop, it looks like Microsoft may have the best AtomPub-based blog client around. I wonder when MarsEdit and Ecto will get on board with AtomPub.

Toolkits and programming libraries

I already blogged about the Propono 0.6, a Java-based client and server library for AtomPub, which has been updated for final spec. Since then the Apace Abdera project has released Apache Abdera (incubating) 0.3 release is available with a long list of improvements and new features. There are also a couple of usage notes from James Snell. Also on the topic of Abdera, Dan Diephouse has done some work to make Spring and Abdera work well together.

The Perl AtomPub::Client at CPAN has updated for final AtomPub too.

That's all I've got for now. Did I miss any important AtomPub news?

Switched to Google Reader

2007-09-26T08:42:27+00:00

I was pretty impressed how quickly Google was able to help my brother out when his Gmail account apparently disappeared. That makes me feel a lot better about trusting Google to manage my precious data.

Another reason to trust in Google is that they make good stuff. I decided to try Google Reader for a couple of days. I figured I'd be back to NetNewsWire after a couple of days, but now I'm hooked and I'm not sure I'll ever go back. The only things I miss are hierarchical folders and smart-subscriptions, which I was using to subscribe to a search within my subscriptions, e.g. alert me when any of the feeds I'm reading mention "roller". I'd like to see better blog-search integration in Reader and features like FeedDemon's popular topics.

TS-6029 - Beyond Blogging: Feeds in Action

2007-05-10T16:27:29+00:00

As usual, I'm enjoying JavaOne and meeting lots of new people and putting faces to names. I've also been practicing my talk daily so I can give you my best performance, so eat lunch a little early or a little late and come see how it goes. Here are the details:

TS-6029 - Beyond Blogging: Feeds in Action
Friday 05/11/2007 12:10 PM -1:10 PM
Moscone Center Esplanade 307 / 310

Atom protocol interop event

2007-04-05T17:16:06+00:00

I just got approval to attend the Atom protocol interop event at Google April 16 and 17. I'll be bringing at least three Atom protocol implementations: Roller's Atom server, Propono's simple file-based Atom server and Propono's Atom client.

@JavaOne: Beyond Blogging: Feeds in Action

2007-04-04T17:32:34+00:00

As promised here's some more info on my JavaOne 2007 session. It's based in part on the Beyond Blogging presentation that I presented to a tiny audience at the local Tri-XML conference last year. Tim Bray didn't attend my talk, but he read the slides and called them "the single best introduction and overview I've ever seen about feeds and syndication and RSS and Atom and all that stuff." I shouldn't brag. Had he attended the talk he might have had an entirely different opinion, who knows. Anyhow, the presentation has been updated, stream-lined and large portions rewritten to cover ROME and ROME's new Propono sub-project. Here's the outline:

The web is bloggy
    Blogging, XML and web services
    Feeds on the web today
    Feeds as an integration technology
    WS Death Star
Understanding RSS and Atom
    The birth of the RSS
    The RDF fork: RSS 1.0
    Elements of RSS 1.0 (abridged)
    Feed Extension Modules
    The simple fork: RSS 0.92 â€“ RSS 2.0
    Elements of RSS 2.0 (abridged)
    RSS limitations
    Atom Publishing Format
    Elements of Atom (abridged)
    RSS and Atom feed family tree
Consuming feeds with ROME
    It's just XML
    ROME RSS/Atom feed utilities
    How does ROME work?
    ROME SyndFeed model
    How to fetch feeds
    Fetching a feed with ROME Fetcher
Producing feeds with ROME
    Serving feeds: generate XML
    Use your favorite XML tools or...
    Generating Atom with ROME
    Serving feeds
    Cache cache cache
    Serving Atom with ROME
    Feed auto-discovery
    Serving valid feeds
Publishing with ROME Propono
    Atom Publishing Protocol (APP)
    What does APP do?
    How does it do all that? The REST way
    APP Service Document
    An Atom collection <feed>
    Getting an APP collection - with paging
    ROME Propono
    ROME Propono Atom Client API
RSS/Atom trends
For More Information
Summary
Q & A

And for the folks who've written to me about Propono, the new ROME subproject devoted to publishing via Atom protocol (and the MetaWeblog API): I hope to commit the code to ROME and starting blogging about it this week.

@ApacheConEU: Roller and blogs as a web dev. platform

2007-03-27T15:27:04+00:00

Last week was deadline week for JavaOne and ApacheCon EU presentations, so I was busy. Fortunately for me, other deadlines were postponed, I did some begging for time and I actually had time to take a short vacation; a family reunion at Stone Mountain park, Georgia.

ApacheCon EU is only a couple of weeks away now and it's before JavaOne so I'll tell you about my ApacheCon talk first. My ApacheCon EU talk is a new. The title is "Roller and blogs as a web development platform" and it explains how blogs, planets, wikis and feeds can be automated and integrated. And how Apache Roller can be extended and customized via templates, scripting and plugins. Here's an outline of the talk:

Overview
   The self-service web
   With no code at all
   Or with a little...
   Feed based integration
Blog, wiki and feed Web services
   MetaWeblog API, methods and Java examples
   Propono Blog Client and Java example
   Atom Publishing Protocol
   Service Doc, Collections and Entries
   Propono Atom Client and Java example
   Roller Admin Interface
   WikiRPCInterface
Blog customization via templates
   Template Editor
   Weblog Templates
   Model objects
   Data Model
   Generating JSON for Dojo and screenshot
Blog server customization via plugins
   Which parts of Roller API to use
   Weblog Entry Plugins and examples
   Page Model Plugins
   Page Rendering & Renderer plugins
   Request Mapping & Request Mapper plugins
   Comment Validator plugins
Example: Scripting languages in Roller
   BSF Renderer plugin
   JRuby via BSF Renderer plugin
   Other Renderer plugins
   Roller admin scripting with Groovy
Planet server aggregation
   What is a Planet server?
   Roller-Planet
   Roller-Planet plans
Use case: Software business blogs
   Blogs in development
   Development Dashboard
   Blogs in Marketing
   Product news & links blogs
   Developer & evangelist blogs
   Blogs in the on-line store
For more information
Summary
Q & A

Monitoring wikis worldwide

2005-01-01T12:41:06+00:00

Newsfeed search engines like Technorati, Feedster, and PubSub make it easy to monitor blogs and news sites. You can subscribe to a search newsfeed to be alerted whenever a blog entry or news items matches your search criteria. But how do you monitor all of the wikis of the world? The newsfeed search engines don't monitor wiki recent changes newsfeeds, or do they?

I googled and turned up some wiki pages on InterWikiSearchEnginesDiscussion and UnifiedRecentChanges. Looks like there is plenty more work to be done in this area.