Soap4r Rack Middleware

This small library provides a Rack Middleware interface to exposing Soap4r server endpoints. This is a lightweight alternative to using ActionWebService for exposing SOAP in a Rails application, as well as allowing SOAP endpoints in any other Rack-based application. It's been tested with Rails 2.3.x, but should work fine in Rails 3 as well.

$ gem install soap4r-middleware

First, get yourself some Soap4r endpoint code. The easiest way to do this is to generate it from a WSDL file. Details are in the Soap4r documentation, or see http://dev.ctor.org/soap4r/wiki/HowtouseWSDL4R , but basically:

$ wsdl2ruby.rb --wsdl /path/to/definiton.wsdl --type server

You'll get some generated files. One of them will be named like *APIService.rb, near the bottom will be a class of the same name. To enable middleware functionality, you want to copy this class' initialization code into a new class that subclasses Soap4r::Middleware::Base, and replace the initialize method with a block passed to setup. For instance:

gem 'soap4r-middleware' # or use Bundler
require 'soap4r-middleware'

class MyAPIMiddleware < Soap4r::Middleware::Base
  setup do
    self.endpoint = %r{^/url/to/soap/endpoint/}
    servant MyAPIPort.new
    MyAPIPort::Methods.each do |definitions|
      opt = definitions.last
      if opt[:request_style] == :document
        @router.add_document_operation(servant, *definitions)
      else
        @router.add_rpc_operation(servant, *definitions)
      end
    end
    self.mapping_registry = UrnMyAPIMappingRegistry::EncodedRegistry
    self.literal_mapping_registry = UrnMyAPIMappingRegistry::LiteralRegistry
  end
end

Then use this middleware anywhere you'd use a Rack middleware. It doubles as a Rack application as well, so you can host it directly using run MyAPIMiddleware.new in your rackup.ru file.

I guess I could wrap wsdl2ruby.rb and make this automatic.

Sometimes you just gotta SOAP. Might as well make it suck as little as possible.