Passing a Python List to a WCF Service

Question

I am trying to pass a list (or array, collection) of strings from python to the WCF service endpoint

WCF Interface:

[OperationContract] string[] TestList(IEnumerable<string> vals); 

Binding in Web.config:

 <endpoint address="http://localhost:13952/Service/Endpoint.svc" binding="basicHttpBinding" contract="Service.IEndpoint"> 

Python code calling the service:

 from suds.client import Client url = 'http://localhost:13952/Service/Endpoint.svc?wsdl' client = Client(url) result = client.service.TestList(('a', 'b', 'c')) 

Resulting error:

 suds.WebFault: Server raised fault: 'The formatter threw an exception while trying to deserialize the message: There was an error while trying to deserialize parameter http://tempuri.org/:vals. The InnerException message was 'Error in line 1 position 310. Expecting state 'Element'.. Encountered 'Text' with name '', namespace ''. '. Please see InnerException for more details.' 

I will try to catch packets using WireShark and try to debug from there. Hoping someone knows a simple solution for this.

Thanks.

Answer 1

You need a Suds factory client. So, the important part that you are missing is client.factory.create('ArrayOfString') .

See unit test below:

 #!/usr/bin/env python import unittest import suds from suds.client import Client class TestCSharpWebService(unittest.TestCase): def setUp(self): url = "http://localhost:8080/WebService.asmx?wsdl=0" self.client = Client(url) def test_service_definition(self): # You can print client to see service definition. self.assertTrue("orderAlphabetically" in self.client.__str__()) self.assertTrue("ArrayOfString" in self.client.__str__()) def test_orderAlphabetically_service(self): # Instanciate your type using the factory and use it. ArrayOfString = self.client.factory.create('ArrayOfString') ArrayOfString.string = ['foo', 'bar', 'foobar', 'a', 'b', 'z'] result = self.client.service.orderAlphabetically(ArrayOfString) # The result list contains suds.sax.text.Text which acts like a string. self.assertEqual( type(result.string[0]), suds.sax.text.Text) self.assertEqual( [str(x) for x in result.string], ['a', 'b', 'bar', 'foo', 'foobar', 'z']) if __name__ == '__main__': unittest.main() 

I started the web service in MonoDevelop 3 and Mono 2.10.

 namespace WebServiceMono { using System.Linq; using System.Web.Services; using System.Collections.Generic; public class WebService : System.Web.Services.WebService { [WebMethod] public string[] orderAlphabetically (List<string> list) { var result = list.OrderBy (s => s); return result.ToArray (); } } }