How can I unit test code that sends a SOAP web-service request?

Question

I want to write a unit test for some code that generates a SOAP message with an attachment and sends it:

SOAPConnectionFactory factory = SOAPConnectionFactory.newInstance();
conn = factory.createConnection();
conn.call(message, endpoint);

where the factory is a javax.xml.soap.SOAPConnectionFactory

I don't care about any response coming back but I want to be able to verify the message that gets sent. The code is going to be refactored and I want to make sure it sends that same messages afterwards as before.

Is there a framework i can use to create a mock endpoint that will let me analyse the request in my test? If so, some sample code would be very useful.

Answer 1

There is a java.net project called WSUnit that should help. It is basically a listener servlet which listens for messages. You can send messages to it and verify the content of the message using XMLUnit.

Answer 2

Use JMock. JMock allows you to test for behavior rather than state changes. To do this, you'll need to encapsulate the SOAPCOnnectionFactory.newInstance() method in a diffent object:

public class MySOAPConnectionFactory {

    public SOAPConnectionFactory getConnection() {
        return SOAPConnectionFactory.newInstance();
}

Use an object of the new class in your code.

conn = mySOAPConnectionFactory.getConnection();
conn.call( message, endpoint );

Then, in your test, substitute a Mock object for the Factory, which will return a Mock Connection. Set expectations on the Mock Connection expecting the call you're looking for.

final SOAPConnectionFactory mockConnection = mockery.mock(SOAPConnectionFactory.class);
final SOAPConnection mockSoapConnection = mockery.mock(SOAPConnection.class);
foo.setMySOAPConnectionFactory( mockConnectionFactory );
try {
        mockery.checking( new Expectations() {

        {
            atLeast( 1 ).of( mockConnectionFactory ).getConnection();
            will( returnValue( mockSoapConnection ) );
            atLeast( 1 ).of( mockConnection ).call(SOME_MESSAGE, ENDPOINT);
        }
        } );

Answer 3

I had a look at WSUnit as suggested in another answer which seems to be available as an eclipse plug-in or as a war I'd deploy to tomcat. It seems overkill that my test would need to depend on either of these things.

I hunted a bit more and found a useful approach using jetty. The code is in 3 unfortunately non-formatted pieces. at http://jpz-log.info/archives/2006/08/16/unit-testing-a-http-client-with-jetty/ I recommend copying and pasting them to an IDE and formatting them there before reading.

The gist of it is to start a Jetty server and dummy servlet (written specifically for the test) within the test and examine the request in the doGet or doPost methods of the servlet.