Lambda the Ultimate

"Web Services" are kind of like the new XML. Useful if you know what you are doing. But mostly just a way for people to write articles that include a stock quote example and little else.

<%@ WebService Language="C#" Class="Hello" %>

using System.Web.Services;

[WebService(Namespace="urn:Hello")]

public class Hello { [ WebMethod ] public string sayHello(string name) { return "Hello " + name; } }

Sure, it's annoying as hell. But how is that much different from what you have to do in Java, to do a hello world that prints to stdout? in JSP, you don't need all the class mumbo-jumbo, but Sun evidentally figured out it was silly to require it. The author of this believes that there is only one reason for this kind of overhead: "Microsoft tries to make it so complex that you have to use their tools." Does anyone else follow this reasoning? Yeah, it sucks, but it's not like emacs can't generate that kind of template. MS is trying to lock you into their tools, but you best believe it's not by using stupid syntax.

Here's the equivalent in GLUE and Java. I'll publish an example using my favorite scripting language (JScheme) before too long that simplifies this even more. One big difference between GLUE and .NET is that GLUE allows the application code to be separate from the "publishing code".

There is "Web Services" the industry topic. This is simply the "next thing" like EJB was, and CORBA before that.

There are also lower-case "web services", which are the toolkits that are easy to use to implement all kinds of useful distributed computing patterns that go beyond stock quotes or even purchase orders.

I think most people are kicking the tires of "Web Services" and will begin to discover there are useful "web services" (lower-case) behind the hype.

Sure, one web services is nice. When you build entire enterprise systems around this architecture, reliability will suddenly become important. Impact analysis (think Y2K scenarios) will become essential. And so on, and so forth.

To me the Web is the ultimate example of "less is more". You hit a web site and you're never sure what you're going to get. Will the server respond, will it timeout, will your browser gork the HTML, does it require a plugin you don't have, etc. And yet, somehow, it all works. Web services take the same approach, which to me is more important than the use of XML.

For example, classic client/server usually takes a one-to-many approach (load balancers notwithstanding). There is one server that is pivotal to the application with the clients providing the user interface. With web services its much more a many-to-many approach. A single client will utilize services from several providers to provide its functionality, and if one service is gone, well life goes on.

Also, like the browser, the endpoints must be programmed to expect and handle the worst: dropped connections, missing packets, data errors, bad formatting, etc. IMO script environments are actually better at this sort of thing.

All this is very theoretical for the time being, as serious web services have yet to appear. Maybe they never will, but I sure hope they do.

Any links to all this cool stuff?