Mike Admire’s Blog

OK, to get this out of the way.  I know, SOAP is lame and REST is cool.  However, there may still be times when you need to query data from a SOAP web service.  This article is an attempt to document the process of retrieving and working with that data.

In this example I will describe how to query the WSDL to get a list of methods and parameters, and use that to submit the method call.  I will be calling a web service method called ‘webMethod’ that accepts one parameter called ‘publishDate’.  If you don’t already know this information about the web service you are communicating with, there is a free tool called SoapUI that works pretty well.  It’s written in Java, so you should be able to get it to work on about any platform.

Depending on the version of Ruby you are running, the first thing that may be required is to install soap4r:

gem install soap4r

Next is to set the location of the WSDL file on the web server, set the encoding, and instantiate the driver:

require ’soap/wsdlDriver’
wsdl = ‘http://server/WebService.asmx?WSDL’
driver = SOAP::WSDLDriverFactory.new(wsdl).create_rpc_driver
XSD::Charset.encoding = ‘UTF8′

This next line will create two logs in the directory of the process called devLog_webMethod_response.xml and devLog_webMethod_request.xml that will show the raw request and response each time the process is called.  In place of webMethod will be the actual method name of the web service being called.  This can be commented out when the application is moved to production.

driver.wiredump_file_base = “devLog”

Now it’s time to retrieve the data:

@response = driver.webMethod(:publishDate => ‘2008-09-01‘)

At this point @response contains the XML response from the web service.  In order to retrieve the data we will need to know a little bit about the structure of the XML.  We can find out this information by opening the log file created by the previous step.  Let’s open devLog_webMethod_response.xml:

OK, so here we have two articles that contain the data we are after and they are both inside the WebMethodResult tags.  So to access those bits we might do something like:

@response.webMethodResult.article.each do |article|
puts article["Name"]
puts article["Headline"]
puts article["Body"]
end

That works great as long as there is always more than one article.  If, on the other hand, there is only one article in the result, it is no longer an array and the .each method will fail.  So to get around this we can move our logic to a method and then test the article first to see which way we should handle it.  So the previous code might be rewritten as:

def print_article(article)
puts article["Name"]
puts article["Headline"]
puts article["Body"]
end

if(@response.webMethodResult.article.is_a?(Array))
@response.webMethodResult.article.each do |article|
print_article(article)
end
else
print_article(@response.webMethodResult.article)
end


If you are asked to do some work with SOAP based web services, hopefully this makes it a little easier to get up and running.

I just installed ruby 1.8.7 on a Windows machine and when I started IRB:

The fix:

1. Go to http://gnuwin32.sourceforge.net/packages/readline.htm and download the binaries zip file.
2. Unzip the file.
3. Change directory to the new directory created by unzipping the file.
4. Change directory to the bin directory.
5. Copy the readline5.dll file.
6. Change directory to your ruby/bin directory (for me this is C:\ruby\bin).
7. Paste readline5.dll file there.
8. Rename file readline.dll.

As long as your ruby\bin directory is set in your PATH environment variable, that should take care of the problem.

I just went through the process of setting up a new Linux desktop for Rails development.  In an effort to keep it short and to the point, I’ve trimmed up some of the info that I found useful from wiki.rubyonrails.org.  This is just a basic development stack.  I plan to write another post on the editors that I’ve tried and what I’ve found to work best for me so far.  Anyway, let’s get started.  I tend to work primarily at a command prompt, so that’s the method I’ve described here.  Open a terminal window and follow along:

sudo apt-get install ruby rdoc libyaml-ruby libzlib-ruby ri libopenssl-ruby ruby1.8-dev build-essential

You don’t want to install the rubygems package from the Ubuntu repository.  It is consistently out of date, so you will need to pull the tarball down from RubyForge:

wget http://rubyforge.org/frs/download.php/38646/rubygems-1.2.0.tgz
tar xvzf rubygems-1.2.0.tgz
cd rubygems-1.2.0
sudo ruby setup.rb

At least with the versions I’ve installed, I had to create a symbolic link to gem1.8:

sudo ln -s /usr/bin/gem1.8 /usr/bin/gem

You should now be able to do a gem update:

sudo gem update --system

And install Rails:

sudo gem install rails

Now it’s time to take care of the database installation:

sudo apt-get install mysql-server libsqlite3-0 libsqlite3-dev
sudo gem install mysql sqlite3-ruby

If you want to install RMagick:

sudo apt-get install imagemagick libmagick9-dev
sudo gem install rmagick

That should do it.  Now go have some fun!

Justin Etheredge has put together an excellent series of tutorials for setting up and getting started with IronRuby on his site.

• Getting IronRuby Up and Running
• Running Applications in IronRuby
• A series on IronRuby for C# developers

I recently upgraded my laptop to 4 Gigs of RAM and needed to upgrade Windows to the 64 bit version in order to utilize it. After installing everything and getting it all setup, I needed to do some work on an existing Rails application.  I pull it out of my Subversion repository, create the dev and test databases, and run ‘rake db:migrate’ only to get this message:

I’m pretty confident that MySQL is installed correctly and I have the databases and permissions setup correctly.  A quick Google search tells me that others have experienced the same issue and they were able to resolve it by finding the dll and copying it to the ruby/bin directory. So…

copy "C:\Program Files\MySQL\MySQL Server 5.0\bin\libmySQL.dll" C:\ruby\bin\

OK, fire up rake again and I get the same error. Back to Google again and after a bit more digging I find that there is an issue with Ruby support in the 64 bit version of MySQL. So I head back to the MySQL website and download the 32 bit zip version without the installer. Open it, navigate to the bin directory and copy libmysql.dll to the ruby/bin directory. This has taken care of the issue and I haven’t had any problems working with the 64 bit version of MySQL using the 32 bit library in Ruby.