tisdag 14 april 2015

Ok, ok I get it... So this Node thingy IS actually quite cool...

I consider myself a polyglot developer who typically uses the best tools for the particular task at hand. Nevertheless when it comes to actually building production ready applications my main language has historically been within the JVM, more times than not relying on the always trusty Java ecosystem with it's abundance of libraries and frameworks.

Today I really got one of those OMGOD moments when you realize just how easy alternative technologies makes your life comparing to what you usually have to keep up with.

At my current customer project we unfortunately have to deal with a remote external SOAP service, which in my and most developers opinion is a protocol born out of hell and is the perfect example of an over engineered solution to something that should be pretty simple.

After dealing with a botched release due to threading problems and bugs within the SOAP framework we used I intended to switch to CXF, which is probably the most popular JAX-WS implementation in Java land.

Many hours later I had a working client after tearing my hair out fighting questions such as:

  • How do we authenticate using WS-Security
  • Which JAR's to include in the Maven build? (CXF has a lot of modules)
  • How to make the JAXB code generation behave well and produce the types of classes we need
  • How to intercept and log relevant request / responses over the wire
  • How to cope with threading, JAX-WS is not thread safe while CXF as an implementation claims to be
  • How to configure CXF to use our logging framework of choice
  • etc...

You get the idea, a lot of ceremony just to create something that could send structured data over the wire and parse responses into something that we can work with.

Just out of curiosity I went ahead and started investigating how you would create a soap client in Node.js land as I have previously built a couple of lightweight internal Node apps for testing, service bridging etc. My first thought was that the cool JS kids would probably never even poke a stick at something like SOAP, so I did not expect to find any good NPM modules for it.

Turns out that even JS developers aren't immune to the protocol madness of SOAP and someone actually went ahead and wrote a very clean and simple client and service module. After reading the example (https://github.com/vpulim/node-soap) and about 5 minutes of experimenting I was up and running. This was what it took to create the same thing I fought for hours with CXF.
npm install soap

  var soap = require('soap');
  var url = 'gateway.wsdl'; //local file, could also be a remote http url
  var args = {};

  soap.createClient(url, function(err, client) {
    //WS-Security UserNameToken out of the box
    client.setSecurity(new soap.WSSecurity('myUser', 'myPassword'));
    //GetProducts is an operation in the wsdl
    client.GetProducts(args, function(err, result) {
      if (!err) {
        //Do something valuable with the response, for now just log.
        //Each XML element in the response would become a corresponding field on the result object
        console.log(JSON.stringify(result, null, 2));
      else {

So, I guess Java and CXF lost this one. And for Node... well it's something you probably should consider learning ASAP. Even if you're a grumpy old-school JVM developer like yours truly.