Merge lp:~allenap/maas/discover-storage-capacity--bug-1387380--1.7 into lp:maas/1.7

[Gavin Panella]

Backport of r3316 from lp:maas: Updated XPath expression for discovering storage capacity from lshw XML.

The lshw format has evolved. The new expression attempts to cope with both old and new formats.

[Christian Reis (kiko)]

review: Approve

=== modified file 'src/metadataserver/models/commissioningscript.py'
--- src/metadataserver/models/commissioningscript.py	2014-10-22 12:29:54 +0000
+++ src/metadataserver/models/commissioningscript.py	2014-10-30 12:45:49 +0000
@@ -139,9 +139,15 @@
     div 1024 div 1024
 """
 
+# Select <node class="disk"><size units="bytes">1234</size></node>, or,
+# failing that, <node class="volume"><size units="bytes">1234</size></node>
+# that's not nested within a <node class="disk"></node>.
 _xpath_storage_bytes = """\
-    sum(//node[@class='volume']/size[@units='bytes'])
-    div 1024 div 1024
+    (
+        //node[@class='disk'] |
+        //node[not(ancestor::node[@class='disk']) and @class='volume']
+    )
+    /size[@units='bytes'] div 1024 div 1024
 """
 
 
 
=== modified file 'src/metadataserver/models/tests/test_noderesults.py'
--- src/metadataserver/models/tests/test_noderesults.py	2014-10-22 12:29:54 +0000
+++ src/metadataserver/models/tests/test_noderesults.py	2014-10-30 12:45:49 +0000
@@ -620,6 +620,36 @@
         node = reload_object(node)
         self.assertEqual(764435, node.storage)
 
+    def test_hardware_updates_storage_1387380_bad(self):
+        # Hardware data from bug 1387380 (the "bad" node).
+        node = factory.make_Node()
+        xmlbytes = dedent("""\
+            <node id="disk" claimed="true"
+                    class="disk" handle="SCSI:00:00:00:00">
+                <size units="bytes">120034123776</size>
+            </node>
+        """).encode("utf-8")
+        update_hardware_details(node, xmlbytes, 0)
+        node = reload_object(node)
+        self.assertEqual(114473, node.storage)
+
+    def test_hardware_updates_storage_1387380_good(self):
+        # Hardware data from bug 1387380 (the "good" node).
+        node = factory.make_Node()
+        xmlbytes = dedent("""\
+            <node id="disk" claimed="true"
+                    class="disk" handle="SCSI:00:00:00:00">
+                <size units="bytes">120034123776</size>
+                <node id="volume" claimed="true" class="volume" handle="">
+                    <size units="bytes">120033075200</size>
+                    <capacity>120033075200</capacity>
+                </node>
+            </node>
+        """).encode("utf-8")
+        update_hardware_details(node, xmlbytes, 0)
+        node = reload_object(node)
+        self.assertEqual(114473, node.storage)
+
     def test_hardware_updates_ignores_empty_tags(self):
         # Tags with empty definitions are ignored when
         # update_hardware_details gets called.