WSMAN enumerate fails to return all entries

When querying an enumeration using the WSMAN enumerate method, not all
entries are returned if there are more than max_elems (default of 100)
in the enumeration.

When querying an enumeration, the first response returns <wsman:Items>
in the body.  Successive pulls, however, contain <wsen:Items>.

The old code always queried for <wsen:Items>, which caused the first
batch of attributes to be dropped only when the number of entries in
the enumeration exceeded max_elems.

This patch queries for <wsman:Items> in the first response, and for
<wsen:Items> in successive responses.

Change-Id: I2e9036b562c7d7ba5af188dd552b6c67388bb02c
Closes-Bug: #1659052

dracclient/tests/test_wsman.py

@@ -68,7 +68,7 @@ class ClientTestCase(base.BaseTest):
         foo_resource_uri = 'http://FooResource'
         bar_resource_uri = 'http://BarResource'
         self.assertEqual(
-            3, len(resp_xml.findall('.//{%s}FooResource' % foo_resource_uri)))
+            4, len(resp_xml.findall('.//{%s}FooResource' % foo_resource_uri)))
         self.assertEqual(
             1, len(resp_xml.findall('.//{%s}BazResource' % bar_resource_uri)))
         self.assertEqual(

dracclient/tests/wsman_mocks/wsman-enum_context-1.xml

@@ -1,6 +1,8 @@
 <s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope"
             xmlns:wsa="http://schemas.xmlsoap.org/ws/2004/08/addressing"
-            xmlns:wsen="http://schemas.xmlsoap.org/ws/2004/09/enumeration">
+            xmlns:wsen="http://schemas.xmlsoap.org/ws/2004/09/enumeration"
+            xmlns:wsman="http://schemas.dmtf.org/wbem/wsman/1/wsman.xsd"
+            xmlns:n1="http://FooResource">
   <s:Header>
     <wsa:To>http://schemas.xmlsoap.org/ws/2004/08/addressing/role/anonymous</wsa:To>
     <wsa:Action>http://schemas.xmlsoap.org/ws/2004/09/enumeration/EnumerateResponse</wsa:Action>
@@ -10,6 +12,11 @@
   <s:Body>
     <wsen:EnumerateResponse>
       <wsen:EnumerationContext>enum-context-uuid</wsen:EnumerationContext>
+      <wsman:Items>
+        <n1:FooResource>
+          <n1:InstanceID>1</n1:InstanceID>
+        </n1:FooResource>
+      </wsman:Items>
     </wsen:EnumerateResponse>
   </s:Body>
 </s:Envelope>

dracclient/tests/wsman_mocks/wsman-enum_context-2.xml

@@ -14,7 +14,7 @@
       <wsen:EnumerationContext>enum-context-uuid</wsen:EnumerationContext>
       <wsen:Items>
         <n1:FooResource>
-          <n1:InstanceID>1</n1:InstanceID>
+          <n1:InstanceID>2</n1:InstanceID>
         </n1:FooResource>
       </wsen:Items>
     </wsen:PullResponse>

dracclient/tests/wsman_mocks/wsman-enum_context-3.xml

@@ -13,10 +13,10 @@
       <wsen:EnumerationContext>enum-context-uuid</wsen:EnumerationContext>
       <wsen:Items>
         <n1:FooResource>
-          <n1:InstanceID>2</n1:InstanceID>
+          <n1:InstanceID>3</n1:InstanceID>
         </n1:FooResource>
         <n1:FooResource>
-          <n1:InstanceID>3</n1:InstanceID>
+          <n1:InstanceID>4</n1:InstanceID>
         </n1:FooResource>
       </wsen:Items>
     </wsen:PullResponse>

dracclient/tests/wsman_mocks/wsman-enum_context-4.xml

@@ -12,7 +12,7 @@
     <wsen:PullResponse>
       <wsen:Items>
         <n1:BazResource>
-          <n1:InstanceID>4</n1:InstanceID>
+          <n1:InstanceID>5</n1:InstanceID>
         </n1:BazResource>
       </wsen:Items>
       <wsen:EndOfSequence/>

dracclient/wsman.py

@@ -105,21 +105,23 @@ class Client(object):
         resp_xml = ElementTree.fromstring(resp.content)
 
         if auto_pull:
-            find_items_query = './/{%s}Items' % NS_WSMAN_ENUM
+            # The first response returns "<wsman:Items>"
+            find_items_wsman_query = './/{%s}Items' % NS_WSMAN
+
+            # Successive pulls return "<wsen:Items>"
+            find_items_enum_query = './/{%s}Items' % NS_WSMAN_ENUM
+
             full_resp_xml = resp_xml
+            items_xml = full_resp_xml.find(find_items_wsman_query)
 
             context = self._enum_context(full_resp_xml)
             while context is not None:
                 resp_xml = self.pull(resource_uri, context, max_elems)
                 context = self._enum_context(resp_xml)
 
-                items_xml = full_resp_xml.find(find_items_query)
-                if items_xml is not None:
-                    # merge enumeration items
-                    for item in resp_xml.find(find_items_query):
+                # Merge in next batch of enumeration items
+                for item in resp_xml.find(find_items_enum_query):
                     items_xml.append(item)
-                else:
-                    full_resp_xml = resp_xml
 
             # remove enumeration context because items are already merged
             enum_context_elem = full_resp_xml.find('.//{%s}EnumerationContext'