Tags: Programming   Ruby on Rails


I was struggling with SOAP for the first time today. No, today is not the first day I bathe! SOAP is some crazy XML communication protocol that seems like overkill to me.

Anyway, I was using Ruby to send and receive the request, and I was getting a baffling SOAP::Mapping::Object object, and I had no idea how to use it. It's a class with dynamically generated methods, and none of the ones I was expecting to see were there.

Blogosphere to the rescue! Marty Haught's Weblog gave a simple trick that saved the day and helped me narrow down my problem to let me see the solution within minutes.

To inspect the resulting object, I was looking at the output of this:

@results.public_methods.sort.join(' ')

Which gives a huge list of methods.

Thanks to Marty, I did this instead:

(@results.public_methods - Object.public_methods).sort.join(' ')

Subtracting Object.public_methods removes all the methods that all Ruby objects get, showing me only the methods that are different. I got this list:

[] []= __add_xmlele_value __xmlattr __xmlele out out=

Sure enough, the "out" method stood out, so I investigated it. A few minutes later, I had navigated through the class and found what I needed. Sweet!

I post this here so that others might discover this simple trick and solve whatever problem is keeping them up late at night.