From: jm <jeffm@...>
Date: 2005-05-13T22:42:44+09:00
Subject: strange error from soap server

I came across this with a larger program to expose the functionality of 
a class via a SOAP interface. The original class passes all test, but 
the SOAP server generates a strange error which I have no idea how to 
solve even after staring at it for hours. The below is a very cut down 
version that produces the same error. It's most likely something to do 
with the way soap4r is being called in the server as the line protocol 
looks correct at a cursory glance, but where and what?

See below for the source code.

the client returns this error
$ ruby lib/dummy_client.rb
Loaded suite lib/dummy_client
Started
E
Finished in 0.015137 seconds.

   1) Error:
test_ping_pong(DummySoap):
SOAP::EncodingStyle::Handler::EncodingStyleError: Illegal parent: .
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:253:in 
`decode_parent'
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:131:in 
`as_struct'
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:232:in 
`decode_parent'
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:131:in 
`as_struct'
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:232:in 
`decode_parent'
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:142:in 
`as_string'
     /usr/lib/ruby/1.8/soap/encodingstyle/soapHandler.rb:202:in 
`decode_tag_end'
     /usr/lib/ruby/1.8/soap/parser.rb:191:in `decode_tag_end'
     /usr/lib/ruby/1.8/soap/parser.rb:152:in `end_element'
     /usr/lib/ruby/1.8/xsd/xmlparser/parser.rb:75:in `end_element'
     /usr/lib/ruby/1.8/xsd/xmlparser/rexmlparser.rb:38:in `tag_end'
     /usr/lib/ruby/1.8/rexml/parsers/streamparser.rb:26:in `parse'
     /usr/lib/ruby/1.8/rexml/document.rb:171:in `parse_stream'
     /usr/lib/ruby/1.8/xsd/xmlparser/rexmlparser.rb:27:in `do_parse'
     /usr/lib/ruby/1.8/soap/parser.rb:90:in `parse'
     /usr/lib/ruby/1.8/soap/processor.rb:39:in `unmarshal'
     /usr/lib/ruby/1.8/soap/rpc/proxy.rb:191:in `unmarshal'
     /usr/lib/ruby/1.8/soap/rpc/proxy.rb:118:in `invoke'
     /usr/lib/ruby/1.8/soap/rpc/proxy.rb:131:in `call'
     /usr/lib/ruby/1.8/soap/rpc/driver.rb:275:in `call'
     /usr/lib/ruby/1.8/soap/rpc/driver.rb:302:in `ping'
     /usr/lib/ruby/1.8/soap/rpc/driver.rb:297:in `ping'
     lib/dummy_client.rb:15:in `test_ping_pong'

1 tests, 0 assertions, 0 failures, 1 errors

this error is logged by the server

[2005-05-13 23:29:07] ERROR ArgumentError: wrong number of arguments (0 
for 1)
         /usr/lib/ruby/1.8/soap/rpc/soaplet.rb:100:in `debug'
         /usr/lib/ruby/1.8/soap/rpc/soaplet.rb:100:in `do_POST'
         /usr/lib/ruby/1.8/webrick/httpservlet/abstract.rb:35:in 
`__send__'
         /usr/lib/ruby/1.8/webrick/httpservlet/abstract.rb:35:in 
`service'
         /usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
         /usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
         /usr/lib/ruby/1.8/webrick/server.rb:155:in `start_thread'
         /usr/lib/ruby/1.8/webrick/server.rb:144:in `start'
         /usr/lib/ruby/1.8/webrick/server.rb:144:in `start_thread'
         /usr/lib/ruby/1.8/webrick/server.rb:94:in `start'
         /usr/lib/ruby/1.8/webrick/server.rb:89:in `each'
         /usr/lib/ruby/1.8/webrick/server.rb:89:in `start'
         /usr/lib/ruby/1.8/webrick/server.rb:79:in `start'
         /usr/lib/ruby/1.8/webrick/server.rb:79:in `start'
         lib/dummy_soap.rb:36

#### dummy_soap.rb
#!/usr/bin/ruby

$LOAD_PATH.unshift File.join(File.dirname(__FILE__), "..","lib")
require 'webrick'
require 'soap/rpc/soaplet'

class Dummy
   def ping
     'pong'
   end
end

class HTTPAccessDenied < WEBrick::HTTPServerError; end

#defaults
basedir = 
File::dirname(File::expand_path(__FILE__)).split('/')[0..-2].join('/')
logfilename = 'dummy.log'
docroot     = File.join(basedir,"html")

s=WEBrick::HTTPServer.new(
   :BindAddress    => "127.0.0.1",
   :Port           => 3000,
   :Logger         => WEBrick::Log::new(logfilename, WEBrick::Log::INFO),
   :DocumentRoot   => docroot
)

srv = SOAP::RPC::SOAPlet.new
srv.add_servant(Dummy.new,'urn:FWControl')


# Mount it at somewhere.
s.mount("/soap", srv)
trap("INT"){ s.shutdown }
s.start

### dummy_client.rb
#!/usr/bin/ruby
$LOAD_PATH.unshift File.join(File.dirname(__FILE__), "..","lib")
require 'test/unit'
require 'soap/rpc/driver'

URL="http://127.0.0.1:3000/soap"
NS="urn:Dummy"

class DummySoap < Test::Unit::TestCase
   def setup
     @proxy = SOAP::RPC::Driver.new(URL,NS)
     @proxy.add_method('ping')
   end
   def test_ping_pong
     assert_equal('pong',@proxy.ping)
   end
end