Restore workaround for redundant namespace declarations on SOAP headers

modules/holodeckb2b-ebms3as4/src/main/java/org/holodeckb2b/as4/multihop/ConfigureMultihop.java

@@ -18,6 +18,7 @@
 
 import java.util.Collection;
 
+import org.apache.axiom.soap.SOAPEnvelope;
 import org.apache.axiom.soap.SOAPHeaderBlock;
 import org.apache.axis2.addressing.AddressingConstants;
 import org.apache.axis2.addressing.EndpointReference;
@@ -83,8 +84,10 @@ protected InvocationResponse doProcessing(final IMessageProcessingContext procCt
             else {
                 // This is a multi-hop message, set the multi-hop target on the eb:Messaging element
                 log.debug("Primary message is a multi-hop UserMessage -> set multi-hop target");
-                final SOAPHeaderBlock ebHeader = Messaging.getElement(procCtx.getParentContext().getEnvelope());
-                ebHeader.setRole(MultiHopConstants.NEXT_MSH_TARGET);
+                final SOAPEnvelope envelope = procCtx.getParentContext().getEnvelope();
+                final SOAPHeaderBlock ebHeader = Messaging.getElement(envelope);
+                final String roleAttr = envelope.getVersion().getRoleAttributeQName().getLocalPart();
+                ebHeader.addAttribute(roleAttr, MultiHopConstants.NEXT_MSH_TARGET, envelope.getNamespace());
             }
         } else if (primMU instanceof IPullRequest) {
             // If the primary message unit is a PullRequest the message is not sent using multi-hop as this is not

modules/holodeckb2b-ebms3as4/src/main/java/org/holodeckb2b/ebms3/packaging/Messaging.java

@@ -18,6 +18,7 @@
 
 import javax.xml.namespace.QName;
 
+import org.apache.axiom.soap.SOAPConstants;
 import org.apache.axiom.soap.SOAPEnvelope;
 import org.apache.axiom.soap.SOAPHeaderBlock;
 import org.holodeckb2b.interfaces.general.EbMSConstants;
@@ -52,8 +53,16 @@ public static SOAPHeaderBlock createElement(final org.apache.axiom.soap.SOAPEnve
             // No existing messaging element, so create a new one
             messaging = env.getHeader().addHeaderBlock(Q_ELEMENT_NAME.getLocalPart(), SOAPEnv.getEbms3Namespace(env));
 
-            // The messaging header must be understood by the MSH (see 5.2.1 core spec)
-            messaging.setMustUnderstand(true);
+            /*
+             * The mustUnderstand attribute is explicitly added here because setting
+             * the mustUnderstand flag on the object results in a redundant namespace
+             * declaration and prefix, e.g. xmlns:mustUnderstand="...."
+             * mustUnderstand:mustUnderstand="true"
+             * Although this isn't incorrect, this additional declaration can confuse
+             * other SOAP processors when performing c14n.
+             */
+            messaging.addAttribute(SOAPConstants.ATTR_MUSTUNDERSTAND,
+                                    SOAPConstants.ATTR_MUSTUNDERSTAND_TRUE, env.getNamespace());
         }
 
         return messaging;

modules/holodeckb2b-ebms3as4/src/test/java/org/holodeckb2b/ebms3/packaging/MessagingTest.java

@@ -17,13 +17,17 @@
 package org.holodeckb2b.ebms3.packaging;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import java.io.ByteArrayOutputStream;
 import java.util.ArrayList;
 
+import org.apache.axiom.soap.SOAPConstants;
 import org.apache.axiom.soap.SOAPEnvelope;
 import org.apache.axiom.soap.SOAPHeader;
 import org.apache.axiom.soap.SOAPHeaderBlock;
+import org.holodeckb2b.as4.multihop.MultiHopConstants;
 import org.holodeckb2b.interfaces.general.EbMSConstants;
 import org.junit.Test;
 
@@ -65,4 +69,39 @@ public void testGetElement() throws Exception {
         assertEquals(soapHeaderBlock.getVersion(),
                 newSoapHeaderBlock.getVersion());
     }
+
+    @Test
+    public void testMustUnderstandSerializesCleanly() throws Exception {
+        SOAPEnvelope env = SOAPEnv.createEnvelope(SOAPEnv.SOAPVersion.SOAP_12);
+        Messaging.createElement(env);
+
+        assertNoRedundantNamespace(env, SOAPConstants.ATTR_MUSTUNDERSTAND);
+    }
+
+    @Test
+    public void testRoleAttributeSerializesCleanly() throws Exception {
+        SOAPEnvelope env = SOAPEnv.createEnvelope(SOAPEnv.SOAPVersion.SOAP_12);
+        SOAPHeaderBlock messaging = Messaging.createElement(env);
+
+        String roleAttr = env.getVersion().getRoleAttributeQName().getLocalPart();
+        messaging.addAttribute(roleAttr, MultiHopConstants.NEXT_MSH_TARGET, env.getNamespace());
+
+        assertNoRedundantNamespace(env, roleAttr);
+    }
+
+    private static String serializeToString(SOAPEnvelope env) throws Exception {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        env.serialize(baos);
+        return baos.toString("UTF-8");
+    }
+
+    private static void assertNoRedundantNamespace(SOAPEnvelope env, String attrName) throws Exception {
+        String xml = serializeToString(env);
+        assertFalse("Redundant namespace declaration 'xmlns:" + attrName + "=' breaks c14n"
+                    + " interoperability.\nActual XML:\n" + xml,
+                    xml.contains("xmlns:" + attrName + "="));
+        assertFalse("Wrongly-prefixed attribute '" + attrName + ":" + attrName + "=' breaks c14n"
+                    + " interoperability.\nActual XML:\n" + xml,
+                    xml.contains(attrName + ":" + attrName + "="));
+    }
 }