Rebooting the Web

For the last few years, the thing all the cool software developers have been talking about is Web Services. Unfortunately, what they’re usually talking about is SOAP and the rest of the W3C web services stack. My experience with SOAP suggests to me that it is not particularly well designed, an opinion others seem to share. But the real issue I have with it is calling the whole business “web services”. I’m all for an open protocol for remote method invocation based on HTTP and XML, but don’t assume that just because you’re using HTTP that means that what you’re doing is “web-like”.

What has made the web so successful is two things: openness and architecture. Openness is really important if you want your technology to gain widespread acceptance, but hyperlinking is what makes the web special. It’s, you know, the “web” part. Hyperlinking is what lets the users of the system generate not only all the content, but the distributed structure as well. And then it lets you do all sorts of other cool things, like have two guys from Stanford write an algorithm to analyze all that user-generated structure and build a great new search engine. When the history of the web is written, I predict that SOAP will be a footnote but that REST will play a key role. SOAP (or some improved version thereof) will have proven to be a useful technology. But if true web services are to be successful at all, REST, with its approach to exposing all of the objects of a system so that third parties can exploit that access in flexible and unpredictable ways, is how it will happen.

Another thing that people seem to overlook is that “web applications” are rarely very web-like. They’re deployed via the web, but not they’re not really part of the web at all. I love the travel site SideStep. It lets me build and manipulate a view of a huge number of airline fares in a way that lets me find exactly what I need. But I can’t link to an individual view of available fares that meet certain criteria and then send that link to a friend.

Wikipedia, on the other hand, lets you link to any topic, any version of a topic, any conversation about that topic, and the list of all edits by any user who has edited that topic. That kind of access to all the information in Wikipedia is what lets clever people create things like the WikiScanner that’s caused such a stir lately. Google Maps is another great example of a web-like web application. Its “Link to this page” offers a link to the current view that you can paste into an email or embed in your own web page. Which is not even to mention its support for an endless variety of mashups that display everything from US Census Bureau statistics to stores where Nintendo Wiis are in stock. Any time you give users a way to exploit your technology and remove the limits on how they can use it, good and surprising things will happen.

Which brings me to my point. I was highly amused to hear that Microsoft had rebooted the web a few months ago. Now if anybody knows something about rebooting, it’s Microsoft, but this was still pretty big news. If you haven’t heard about Silverlight, the new technology that spurred this surprising announcement, perhaps it’s because the rest of the web has continued doing its thing. You’d be forgiven for not noticing the reboot.

Silverlight looks like a really cool technology. But it didn’t, nor will it ever, reboot the web, because it isn’t the web. It lets you deploy applications via the web and it probably “plays well” with the web. But unless Microsoft builds in all sorts of clever ways for people to assemble and exploit this technology in unplanned ways, it will never be a part of the web. And for a company known for trying to strictly control how people use its software, that seems unlikely.

Update (July 4, 2008): Apparently Google agrees about REST. The true mark of REST’s success is that it’s starting to become the default. HTTP APIs are just made that way, without anyone necessarily even calling them “REST”.

Update (November 3, 2008): ProgrammableWeb adds its 1000th entry into its web API directory.  Guess which type of API accounts for 63% of the entries?