"No Action header was found" error message while using SOAP webservice

Question

Getting following error while consuming SOAP webservice in iOS App

"No Action header was found with namespace 'http://www.w3.org/2005/08/addressing' for the given message."

The same webservice working fine in SOAP UI Tool.

Following is the request format

NSString *data = @"<soap:Envelope xmlns:soap=\"http://www.w3.org/2003/05/soap-envelope\" xmlns:tem=\"http://tempuri.org/\">
<soap:Header></soap:Header>
<soap:Body><tem:GetEvaluators></tem:GetEvaluators></soap:Body>
</soap:Envelope>";

NSString *url = @"webservice url";
NSData *postData = [data dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:url]];
[request setHTTPMethod:@"POST"];
[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setHTTPBody:postData];
[request setTimeoutInterval:20.0];
[request setValue:@"application/soap+xml;charset=UTF-8" forHTTPHeaderField:@"Content-Type"];
[request setValue:@"http://tempuri.org/IATCService/GetEvaluators" forHTTPHeaderField:@"SOAPAction"];
 NSData *urlData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];

Complete error response received from webservice

<s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope" xmlns:a="http://www.w3.org/2005/08/addressing">
<s:Header>
    <a:Action s:mustUnderstand="1">http://www.w3.org/2005/08/addressing/fault</a:Action>
</s:Header>
<s:Body>
    <s:Fault>
        <s:Code>
            <s:Value>s:Sender</s:Value>
            <s:Subcode>
                <s:Value>a:MessageAddressingHeaderRequired</s:Value>
            </s:Subcode>
        </s:Code>
        <s:Reason>
            <s:Text xml:lang="en-US">No Action header was found with namespace 'http://www.w3.org/2005/08/addressing' for the given message.</s:Text>
        </s:Reason>
        <s:Detail>
            <a:ProblemHeaderQName>a:Action</a:ProblemHeaderQName>
        </s:Detail>
    </s:Fault>
</s:Body>

Any help really appreciated.

Answer 1

We had the same problem with an ASP.NET-based server (error message when using python/suds, same query worked in SoapUi); after a lot of digging, we found that we need to add a SOAP header (as XML element) which contains the action; having the action in the Content-Type or SOAPAction headers was not enough (but does not hurt either). Here's an example of a successful query (from SoapUi):

<SOAP-ENV:Envelope xmlns:ns0="..." xmlns:ns1="http://www.w3.org/2003/05/soap-envelope" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope">
   <SOAP-ENV:Header xmlns:wsa="http://www.w3.org/2005/08/addressing"><wsa:Action>http://www.foo.com/.../SomeJob/getParameters</wsa:Action></SOAP-ENV:Header>
   <ns1:Body>
      <ns0:getParameters>...</ns0:getParameters>
   </ns1:Body>
</SOAP-ENV:Envelope>

With Python and SUDS, this is how we did it:

from suds.sax.element import Element
wsans = ('wsa', "http://www.w3.org/2005/08/addressing")
client.set_options(soapheaders = Element('Action', ns=wsans).setText(action))

The action can be queried from the method, i.e. if you want to call a method client.service.foo, use

action = client.service.foo.method.soap.action

We found this by looking at the SoapUi HTTP log. (We also tried Wireshark, but that would not work because we're trying to use an https server which we don't own.)