Adds deserialization for block_device_mapping

The os-volumes extension adds the ability to boot from a volume
or snapshot by including block_device_mapping in the server create
request. This patch adds code to the xml deserializer so
block_device_mapping can be specified via xml as well.

Fixes bug 1052695

Change-Id: I3e586abb32976df98d70c29b6a021fd01c4c186b

nova/api/openstack/compute/servers.py

@@ -193,6 +193,12 @@ def _extract_server(self, node):
         if security_groups is not None:
             server["security_groups"] = security_groups
 
+        # NOTE(vish): this is not namespaced in json, so leave it without a
+        #             namespace for now
+        block_device_mapping = self._extract_block_device_mapping(server_node)
+        if block_device_mapping is not None:
+            server["block_device_mapping"] = block_device_mapping
+
         # NOTE(vish): Support this incorrect version because it was in the code
         #             base for a while and we don't want to accidentally break
         #             anyone that might be using it.
@@ -206,6 +212,31 @@ def _extract_server(self, node):
 
         return server
 
+    def _extract_block_device_mapping(self, server_node):
+        """Marshal the block_device_mapping node of a parsed request"""
+        node = self.find_first_child_named(server_node, "block_device_mapping")
+        if node:
+            block_device_mapping = []
+            for child in self.extract_elements(node):
+                if child.nodeName != "mapping":
+                    continue
+                mapping = {}
+                attributes = ["volume_id", "snapshot_id", "device_name",
+                              "virtual_name", "volume_size"]
+                for attr in attributes:
+                    value = child.getAttribute(attr)
+                    if value:
+                        mapping[attr] = value
+                attributes = ["delete_on_termination", "no_device"]
+                for attr in attributes:
+                    value = child.getAttribute(attr)
+                    if value:
+                        mapping[attr] = utils.bool_from_str(value)
+                block_device_mapping.append(mapping)
+            return block_device_mapping
+        else:
+            return None
+
     def _extract_scheduler_hints(self, server_node):
         """Marshal the scheduler hints attribute of a parsed request"""
         node = self.find_first_child_named(server_node,

nova/tests/api/openstack/compute/test_servers.py

@@ -3333,6 +3333,46 @@ def test_request_with_scheduler_hints(self):
                 }}
         self.assertEquals(request['body'], expected)
 
+    def test_request_with_block_device_mapping(self):
+        serial_request = """
+    <server xmlns="http://docs.openstack.org/compute/api/v2"
+     name="new-server-test" imageRef="1" flavorRef="1">
+       <block_device_mapping>
+         <mapping volume_id="7329b667-50c7-46a6-b913-cb2a09dfeee0"
+          device_name="/dev/vda" virtual_name="root"
+          delete_on_termination="False" />
+         <mapping snapshot_id="f31efb24-34d2-43e1-8b44-316052956a39"
+          device_name="/dev/vdb" virtual_name="ephemeral0"
+          delete_on_termination="False" />
+         <mapping device_name="/dev/vdc" no_device="True" />
+       </block_device_mapping>
+    </server>"""
+        request = self.deserializer.deserialize(serial_request)
+        expected = {"server": {
+                "name": "new-server-test",
+                "imageRef": "1",
+                "flavorRef": "1",
+                "block_device_mapping": [
+                    {
+                        "volume_id": "7329b667-50c7-46a6-b913-cb2a09dfeee0",
+                        "device_name": "/dev/vda",
+                        "virtual_name": "root",
+                        "delete_on_termination": False,
+                    },
+                    {
+                        "snapshot_id": "f31efb24-34d2-43e1-8b44-316052956a39",
+                        "device_name": "/dev/vdb",
+                        "virtual_name": "ephemeral0",
+                        "delete_on_termination": False,
+                    },
+                    {
+                        "device_name": "/dev/vdc",
+                        "no_device": True,
+                    },
+                ]
+                }}
+        self.assertEquals(request['body'], expected)
+
 
 class TestAddressesXMLSerialization(test.TestCase):