Why is "wsdl" namespace interjected into action name when using savon for ruby soap communication?

You need to pass an array to soap.input the second element of which is a hash containing the namespace details.

soap.input = [ 
  "ProcessMessage", 
  {"xmlns" => "http://www.starstandards.org/webservices/2005/10/transport"}
]

This should ensure you end up with the name space declaration as an attribute to the main element.

You will probably also end up with a namespace declaration before the element like so

<env:Body>
    <wsdl:ProcessMessage xmlns="........." >
        <payload>
            ......
        </payload>
    </wsdl:ProcessMessage>
</env:Body>

but this was not an issue for me, it was the lack of the namespace attribute that was the issue, not the presence of the namespace before the element.

For my web service I needed to get rid of the "wsdl" namespace on top of Steve's solution.

Tested with Savon 0.9.6:

client = Savon::Client.new "https://example.com/webservice/account.asmx?WSDL"
response = client.request "GetAccount" do
  # Gotcha 1: set default namespace for body elements
  soap.input = ["GetAccount", {"xmlns" => "https://example.com/webservice/"}]
  soap.body = {
    "AccountID" => 1234
  }
  # Gotcha 2: get rid of namespace declaration of body elements
  soap.element_form_default = :unqualified
  # Gotcha 3: set SOAPAction different from default
  http.headers["SOAPAction"] = '"https://example.com/webservice/GetAccount"'
end

Steve, you see that wsdl: in front of ProcessMessage tag? - I thought that was the only thing that was throwing me off but its not ( by the way it's hard set in soap.rb in Savon lib on line 160). That even if I don't spacify it in soap.namespaces - it's hard generated and attached in final xml. Which is not allowed by my service.

While the xml that is generated is a valid xml - it's not complete by the requirments of the service I'm trying to talk to. I.e.: in generated xml,

<?xml version="1.0" encoding="UTF-8"?>

tag is missing, also, I need PayloadManifest in the header,plus I need wsu:created and wsu:expires in my wsse: tag, but they are not implemented, etc., etc. a bunch of other little quirks that are too specific to my case. However soap has a private method = xml_body. Also soap lib in to_xml method is checking whether @xml_body was already set, before generating it's own xml. So I ended up slighly modifying behavior of soap. by making soap.xml_body = publicly accessable. So I was able to do:

response = client.process_message! do |soap| 
soap.action = "http://www.starstandards.org/webservices/2005/10/transport/operations/ProcessMessage"
soap.xml_body = "MY XML STRING GENERATED ELSEWHERE GOES HERE"
end

Which finally works!!!!

I'll suggest this to rubii - if this option becomes available that will solve a lot rare cases - where people can generate their custom xml and use the rest of savon lib.