Merge from trunk

11 files changed, 507 insertions, 53 deletions

diff --git a/nova/api/ec2/__init__.py b/nova/api/ec2/__init__.py
index fccebca5d..20701cfa8 100644
--- a/nova/api/ec2/__init__.py
+++ b/nova/api/ec2/__init__.py
@@ -31,7 +31,7 @@ from nova import log as logging
 from nova import utils
 from nova import wsgi
 from nova.api.ec2 import apirequest
-from nova.api.ec2 import cloud
+from nova.api.ec2 import ec2utils
 from nova.auth import manager
 
 
@@ -319,13 +319,13 @@ class Executor(wsgi.Application):
         except exception.InstanceNotFound as ex:
             LOG.info(_('InstanceNotFound raised: %s'), unicode(ex),
                      context=context)
-            ec2_id = cloud.id_to_ec2_id(ex.instance_id)
+            ec2_id = ec2utils.id_to_ec2_id(ex.instance_id)
             message = _('Instance %s not found') % ec2_id
             return self._error(req, context, type(ex).__name__, message)
         except exception.VolumeNotFound as ex:
             LOG.info(_('VolumeNotFound raised: %s'), unicode(ex),
                      context=context)
-            ec2_id = cloud.id_to_ec2_id(ex.volume_id, 'vol-%08x')
+            ec2_id = ec2utils.id_to_ec2_id(ex.volume_id, 'vol-%08x')
             message = _('Volume %s not found') % ec2_id
             return self._error(req, context, type(ex).__name__, message)
         except exception.NotFound as ex:
diff --git a/nova/api/ec2/admin.py b/nova/api/ec2/admin.py
index d9a4ef999..d8d90ad83 100644
--- a/nova/api/ec2/admin.py
+++ b/nova/api/ec2/admin.py
@@ -28,6 +28,7 @@ from nova import exception
 from nova import flags
 from nova import log as logging
 from nova import utils
+from nova.api.ec2 import ec2utils
 from nova.auth import manager
 
 
@@ -60,7 +61,7 @@ def project_dict(project):
 
 def host_dict(host, compute_service, instances, volume_service, volumes, now):
     """Convert a host model object to a result dict"""
-    rv = {'hostanme': host, 'instance_count': len(instances),
+    rv = {'hostname': host, 'instance_count': len(instances),
           'volume_count': len(volumes)}
     if compute_service:
         latest = compute_service['updated_at'] or compute_service['created_at']
@@ -92,15 +93,18 @@ def vpn_dict(project, vpn_instance):
           'public_ip': project.vpn_ip,
           'public_port': project.vpn_port}
     if vpn_instance:
-        rv['instance_id'] = vpn_instance['ec2_id']
+        rv['instance_id'] = ec2utils.id_to_ec2_id(vpn_instance['id'])
         rv['created_at'] = utils.isotime(vpn_instance['created_at'])
         address = vpn_instance.get('fixed_ip', None)
         if address:
             rv['internal_ip'] = address['address']
-        if utils.vpn_ping(project.vpn_ip, project.vpn_port):
-            rv['state'] = 'running'
+        if project.vpn_ip and project.vpn_port:
+            if utils.vpn_ping(project.vpn_ip, project.vpn_port):
+                rv['state'] = 'running'
+            else:
+                rv['state'] = 'down'
         else:
-            rv['state'] = 'down'
+            rv['state'] = 'down - invalid project vpn config'
     else:
         rv['state'] = 'pending'
     return rv
@@ -116,7 +120,8 @@ class AdminController(object):
 
     def describe_instance_types(self, context, **_kwargs):
         """Returns all active instance types data (vcpus, memory, etc.)"""
-        return {'instanceTypeSet': [db.instance_type_get_all(context)]}
+        return {'instanceTypeSet': [instance_dict(v) for v in
+                                   db.instance_type_get_all(context).values()]}
 
     def describe_user(self, _context, name, **_kwargs):
         """Returns user data, including access and secret keys."""
@@ -279,7 +284,7 @@ class AdminController(object):
                                          ", ensure it isn't running, and try "
                                          "again in a few minutes")
             instance = self._vpn_for(context, project)
-        return {'instance_id': instance['ec2_id']}
+        return {'instance_id': ec2utils.id_to_ec2_id(instance['id'])}
 
     def describe_vpns(self, context):
         vpns = []
diff --git a/nova/api/openstack/__init__.py b/nova/api/openstack/__init__.py
index 0b50d17d0..143b1d2b2 100644
--- a/nova/api/openstack/__init__.py
+++ b/nova/api/openstack/__init__.py
@@ -33,6 +33,7 @@ from nova.api.openstack import backup_schedules
 from nova.api.openstack import consoles
 from nova.api.openstack import flavors
 from nova.api.openstack import images
+from nova.api.openstack import limits
 from nova.api.openstack import servers
 from nova.api.openstack import shared_ip_groups
 from nova.api.openstack import users
@@ -115,16 +116,23 @@ class APIRouter(wsgi.Router):
 
         mapper.resource("image", "images", controller=images.Controller(),
                         collection={'detail': 'GET'})
+
         mapper.resource("flavor", "flavors", controller=flavors.Controller(),
                         collection={'detail': 'GET'})
+
         mapper.resource("shared_ip_group", "shared_ip_groups",
                         collection={'detail': 'GET'},
                         controller=shared_ip_groups.Controller())
 
+        _limits = limits.LimitsController()
+        mapper.resource("limit", "limits", controller=_limits)
+
 
 class APIRouterV10(APIRouter):
+    """Define routes specific to OpenStack API V1.0."""
+
     def _setup_routes(self, mapper):
-        APIRouter._setup_routes(self, mapper)
+        super(APIRouterV10, self)._setup_routes(mapper)
         mapper.resource("server", "servers",
                         controller=servers.ControllerV10(),
                         collection={'detail': 'GET'},
@@ -132,8 +140,10 @@ class APIRouterV10(APIRouter):
 
 
 class APIRouterV11(APIRouter):
+    """Define routes specific to OpenStack API V1.1."""
+
     def _setup_routes(self, mapper):
-        APIRouter._setup_routes(self, mapper)
+        super(APIRouterV11, self)._setup_routes(mapper)
         mapper.resource("server", "servers",
                         controller=servers.ControllerV11(),
                         collection={'detail': 'GET'},
diff --git a/nova/api/openstack/common.py b/nova/api/openstack/common.py
index 8106f841b..f85d1df9d 100644
--- a/nova/api/openstack/common.py
+++ b/nova/api/openstack/common.py
@@ -15,10 +15,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import re
+from urlparse import urlparse
+
+import webob
+
 from nova import exception
-from webob import exc
-import webob.exc
 
 
 def limited(items, request, max_limit=1000):
@@ -106,7 +107,13 @@ def get_image_id_from_image_hash(image_service, context, image_hash):
 
 
 def get_id_from_href(href):
-    m = re.match(r'http.+/.+/(\d)+$', href)
-    if not m:
-        raise exc.HTTPBadRequest(_('could not parse id from href'))
-    return int(m.group(1))
+    """Return the id portion of a url as an int.
+
+    Given: http://www.foo.com/bar/123?q=4
+    Returns: 123
+
+    """
+    try:
+        return int(urlparse(href).path.split('/')[-1])
+    except:
+        raise webob.exc.HTTPBadRequest(_('could not parse id from href'))
diff --git a/nova/api/openstack/faults.py b/nova/api/openstack/faults.py
index 2fd733299..0e9c4b26f 100644
--- a/nova/api/openstack/faults.py
+++ b/nova/api/openstack/faults.py
@@ -61,3 +61,42 @@ class Fault(webob.exc.HTTPException):
         content_type = req.best_match_content_type()
         self.wrapped_exc.body = serializer.serialize(fault_data, content_type)
         return self.wrapped_exc
+
+
+class OverLimitFault(webob.exc.HTTPException):
+    """
+    Rate-limited request response.
+    """
+
+    _serialization_metadata = {
+        "application/xml": {
+            "attributes": {
+                "overLimitFault": "code",
+            },
+        },
+    }
+
+    def __init__(self, message, details, retry_time):
+        """
+        Initialize new `OverLimitFault` with relevant information.
+        """
+        self.wrapped_exc = webob.exc.HTTPForbidden()
+        self.content = {
+            "overLimitFault": {
+                "code": self.wrapped_exc.status_int,
+                "message": message,
+                "details": details,
+            },
+        }
+
+    @webob.dec.wsgify(RequestClass=wsgi.Request)
+    def __call__(self, request):
+        """
+        Return the wrapped exception with a serialized body conforming to our
+        error format.
+        """
+        serializer = wsgi.Serializer(self._serialization_metadata)
+        content_type = request.best_match_content_type()
+        content = serializer.serialize(self.content, content_type)
+        self.wrapped_exc.body = content
+        return self.wrapped_exc
diff --git a/nova/api/openstack/flavors.py b/nova/api/openstack/flavors.py
index 1c440b3a9..c99b945fb 100644
--- a/nova/api/openstack/flavors.py
+++ b/nova/api/openstack/flavors.py
@@ -22,6 +22,7 @@ from nova import context
 from nova.api.openstack import faults
 from nova.api.openstack import common
 from nova.compute import instance_types
+from nova.api.openstack.views import flavors as flavors_views
 from nova import wsgi
 import nova.api.openstack
 
@@ -36,7 +37,7 @@ class Controller(wsgi.Controller):
 
     def index(self, req):
         """Return all flavors in brief."""
-        return dict(flavors=[dict(id=flavor['flavorid'], name=flavor['name'])
+        return dict(flavors=[dict(id=flavor['id'], name=flavor['name'])
                              for flavor in self.detail(req)['flavors']])
 
     def detail(self, req):
@@ -47,14 +48,18 @@ class Controller(wsgi.Controller):
     def show(self, req, id):
         """Return data about the given flavor id."""
         ctxt = req.environ['nova.context']
-        values = db.instance_type_get_by_flavor_id(ctxt, id)
-        values['id'] = values['flavorid']
+        flavor = db.api.instance_type_get_by_flavor_id(ctxt, id)
+        values = {
+            "id": flavor["flavorid"],
+            "name": flavor["name"],
+            "ram": flavor["memory_mb"],
+            "disk": flavor["local_gb"],
+        }
         return dict(flavor=values)
-        raise faults.Fault(exc.HTTPNotFound())
 
     def _all_ids(self, req):
         """Return the list of all flavorids."""
         ctxt = req.environ['nova.context']
-        inst_types = db.instance_type_get_all(ctxt)
+        inst_types = db.api.instance_type_get_all(ctxt)
         flavor_ids = [inst_types[i]['flavorid'] for i in inst_types.keys()]
         return sorted(flavor_ids)
diff --git a/nova/api/openstack/images.py b/nova/api/openstack/images.py
index 98f0dd96b..99c14275a 100644
--- a/nova/api/openstack/images.py
+++ b/nova/api/openstack/images.py
@@ -143,6 +143,7 @@ class Controller(wsgi.Controller):
 
         image = self._service.show(req.environ['nova.context'], image_id)
         _convert_image_id_to_hash(image)
+        self._format_image_dates(image)
         return dict(image=image)
 
     def delete(self, req, id):
@@ -164,3 +165,8 @@ class Controller(wsgi.Controller):
         # Users may not modify public images, and that's all that
         # we support for now.
         raise faults.Fault(exc.HTTPNotFound())
+
+    def _format_image_dates(self, image):
+        for attr in ['created_at', 'updated_at', 'deleted_at']:
+            if image.get(attr) is not None:
+                image[attr] = image[attr].strftime('%Y-%m-%dT%H:%M:%SZ')
diff --git a/nova/api/openstack/limits.py b/nova/api/openstack/limits.py
new file mode 100644
index 000000000..efc7d193d
--- /dev/null
+++ b/nova/api/openstack/limits.py
@@ -0,0 +1,358 @@
+# Copyright 2011 OpenStack LLC.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.import datetime
+
+"""
+Module dedicated functions/classes dealing with rate limiting requests.
+"""
+
+import copy
+import httplib
+import json
+import math
+import re
+import time
+import urllib
+import webob.exc
+
+from collections import defaultdict
+
+from webob.dec import wsgify
+
+from nova import wsgi
+from nova.api.openstack import faults
+from nova.wsgi import Controller
+from nova.wsgi import Middleware
+
+
+# Convenience constants for the limits dictionary passed to Limiter().
+PER_SECOND = 1
+PER_MINUTE = 60
+PER_HOUR = 60 * 60
+PER_DAY = 60 * 60 * 24
+
+
+class LimitsController(Controller):
+    """
+    Controller for accessing limits in the OpenStack API.
+    """
+
+    _serialization_metadata = {
+        "application/xml": {
+            "attributes": {
+                "limit": ["verb", "URI", "regex", "value", "unit",
+                    "resetTime", "remaining", "name"],
+            },
+            "plurals": {
+                "rate": "limit",
+            },
+        },
+    }
+
+    def index(self, req):
+        """
+        Return all global and rate limit information.
+        """
+        abs_limits = {}
+        rate_limits = req.environ.get("nova.limits", [])
+
+        return {
+            "limits": {
+                "rate": rate_limits,
+                "absolute": abs_limits,
+            },
+        }
+
+
+class Limit(object):
+    """
+    Stores information about a limit for HTTP requets.
+    """
+
+    UNITS = {
+        1: "SECOND",
+        60: "MINUTE",
+        60 * 60: "HOUR",
+        60 * 60 * 24: "DAY",
+    }
+
+    def __init__(self, verb, uri, regex, value, unit):
+        """
+        Initialize a new `Limit`.
+
+        @param verb: HTTP verb (POST, PUT, etc.)
+        @param uri: Human-readable URI
+        @param regex: Regular expression format for this limit
+        @param value: Integer number of requests which can be made
+        @param unit: Unit of measure for the value parameter
+        """
+        self.verb = verb
+        self.uri = uri
+        self.regex = regex
+        self.value = int(value)
+        self.unit = unit
+        self.unit_string = self.display_unit().lower()
+        self.remaining = int(value)
+
+        if value <= 0:
+            raise ValueError("Limit value must be > 0")
+
+        self.last_request = None
+        self.next_request = None
+
+        self.water_level = 0
+        self.capacity = self.unit
+        self.request_value = float(self.capacity) / float(self.value)
+        self.error_message = _("Only %(value)s %(verb)s request(s) can be "\
+            "made to %(uri)s every %(unit_string)s." % self.__dict__)
+
+    def __call__(self, verb, url):
+        """
+        Represents a call to this limit from a relevant request.
+
+        @param verb: string http verb (POST, GET, etc.)
+        @param url: string URL
+        """
+        if self.verb != verb or not re.match(self.regex, url):
+            return
+
+        now = self._get_time()
+
+        if self.last_request is None:
+            self.last_request = now
+
+        leak_value = now - self.last_request
+
+        self.water_level -= leak_value
+        self.water_level = max(self.water_level, 0)
+        self.water_level += self.request_value
+
+        difference = self.water_level - self.capacity
+
+        self.last_request = now
+
+        if difference > 0:
+            self.water_level -= self.request_value
+            self.next_request = now + difference
+            return difference
+
+        cap = self.capacity
+        water = self.water_level
+        val = self.value
+
+        self.remaining = math.floor(((cap - water) / cap) * val)
+        self.next_request = now
+
+    def _get_time(self):
+        """Retrieve the current time. Broken out for testability."""
+        return time.time()
+
+    def display_unit(self):
+        """Display the string name of the unit."""
+        return self.UNITS.get(self.unit, "UNKNOWN")
+
+    def display(self):
+        """Return a useful representation of this class."""
+        return {
+            "verb": self.verb,
+            "URI": self.uri,
+            "regex": self.regex,
+            "value": self.value,
+            "remaining": int(self.remaining),
+            "unit": self.display_unit(),
+            "resetTime": int(self.next_request or self._get_time()),
+        }
+
+# "Limit" format is a dictionary with the HTTP verb, human-readable URI,
+# a regular-expression to match, value and unit of measure (PER_DAY, etc.)
+
+DEFAULT_LIMITS = [
+    Limit("POST", "*", ".*", 10, PER_MINUTE),
+    Limit("POST", "*/servers", "^/servers", 50, PER_DAY),
+    Limit("PUT", "*", ".*", 10, PER_MINUTE),
+    Limit("GET", "*changes-since*", ".*changes-since.*", 3, PER_MINUTE),
+    Limit("DELETE", "*", ".*", 100, PER_MINUTE),
+]
+
+
+class RateLimitingMiddleware(Middleware):
+    """
+    Rate-limits requests passing through this middleware. All limit information
+    is stored in memory for this implementation.
+    """
+
+    def __init__(self, application, limits=None):
+        """
+        Initialize new `RateLimitingMiddleware`, which wraps the given WSGI
+        application and sets up the given limits.
+
+        @param application: WSGI application to wrap
+        @param limits: List of dictionaries describing limits
+        """
+        Middleware.__init__(self, application)
+        self._limiter = Limiter(limits or DEFAULT_LIMITS)
+
+    @wsgify(RequestClass=wsgi.Request)
+    def __call__(self, req):
+        """
+        Represents a single call through this middleware. We should record the
+        request if we have a limit relevant to it. If no limit is relevant to
+        the request, ignore it.
+
+        If the request should be rate limited, return a fault telling the user
+        they are over the limit and need to retry later.
+        """
+        verb = req.method
+        url = req.url
+        context = req.environ.get("nova.context")
+
+        if context:
+            username = context.user_id
+        else:
+            username = None
+
+        delay, error = self._limiter.check_for_delay(verb, url, username)
+
+        if delay:
+            msg = _("This request was rate-limited.")
+            retry = time.time() + delay
+            return faults.OverLimitFault(msg, error, retry)
+
+        req.environ["nova.limits"] = self._limiter.get_limits(username)
+
+        return self.application
+
+
+class Limiter(object):
+    """
+    Rate-limit checking class which handles limits in memory.
+    """
+
+    def __init__(self, limits):
+        """
+        Initialize the new `Limiter`.
+
+        @param limits: List of `Limit` objects
+        """
+        self.limits = copy.deepcopy(limits)
+        self.levels = defaultdict(lambda: copy.deepcopy(limits))
+
+    def get_limits(self, username=None):
+        """
+        Return the limits for a given user.
+        """
+        return [limit.display() for limit in self.levels[username]]
+
+    def check_for_delay(self, verb, url, username=None):
+        """
+        Check the given verb/user/user triplet for limit.
+
+        @return: Tuple of delay (in seconds) and error message (or None, None)
+        """
+        delays = []
+
+        for limit in self.levels[username]:
+            delay = limit(verb, url)
+            if delay:
+                delays.append((delay, limit.error_message))
+
+        if delays:
+            delays.sort()
+            return delays[0]
+
+        return None, None
+
+
+class WsgiLimiter(object):
+    """
+    Rate-limit checking from a WSGI application. Uses an in-memory `Limiter`.
+
+    To use:
+        POST /<username> with JSON data such as:
+        {
+            "verb" : GET,
+            "path" : "/servers"
+        }
+
+    and receive a 204 No Content, or a 403 Forbidden with an X-Wait-Seconds
+    header containing the number of seconds to wait before the action would
+    succeed.
+    """
+
+    def __init__(self, limits=None):
+        """
+        Initialize the new `WsgiLimiter`.
+
+        @param limits: List of `Limit` objects
+        """
+        self._limiter = Limiter(limits or DEFAULT_LIMITS)
+
+    @wsgify(RequestClass=wsgi.Request)
+    def __call__(self, request):
+        """
+        Handles a call to this application. Returns 204 if the request is
+        acceptable to the limiter, else a 403 is returned with a relevant
+        header indicating when the request *will* succeed.
+        """
+        if request.method != "POST":
+            raise webob.exc.HTTPMethodNotAllowed()
+
+        try:
+            info = dict(json.loads(request.body))
+        except ValueError:
+            raise webob.exc.HTTPBadRequest()
+
+        username = request.path_info_pop()
+        verb = info.get("verb")
+        path = info.get("path")
+
+        delay, error = self._limiter.check_for_delay(verb, path, username)
+
+        if delay:
+            headers = {"X-Wait-Seconds": "%.2f" % delay}
+            return webob.exc.HTTPForbidden(headers=headers, explanation=error)
+        else:
+            return webob.exc.HTTPNoContent()
+
+
+class WsgiLimiterProxy(object):
+    """
+    Rate-limit requests based on answers from a remote source.
+    """
+
+    def __init__(self, limiter_address):
+        """
+        Initialize the new `WsgiLimiterProxy`.
+
+        @param limiter_address: IP/port combination of where to request limit
+        """
+        self.limiter_address = limiter_address
+
+    def check_for_delay(self, verb, path, username=None):
+        body = json.dumps({"verb": verb, "path": path})
+        headers = {"Content-Type": "application/json"}
+
+        conn = httplib.HTTPConnection(self.limiter_address)
+
+        if username:
+            conn.request("POST", "/%s" % (username), body, headers)
+        else:
+            conn.request("POST", "/", body, headers)
+
+        resp = conn.getresponse()
+
+        if 200 >= resp.status < 300:
+            return None, None
+
+        return resp.getheader("X-Wait-Seconds"), resp.read() or None
diff --git a/nova/api/openstack/servers.py b/nova/api/openstack/servers.py
index 461bf5989..740a9bb57 100644
--- a/nova/api/openstack/servers.py
+++ b/nova/api/openstack/servers.py
@@ -22,6 +22,7 @@ from xml.dom import minidom
 from webob import exc
 
 from nova import compute
+from nova import context
 from nova import exception
 from nova import flags
 from nova import log as logging
@@ -136,8 +137,10 @@ class Controller(wsgi.Controller):
             for k, v in env['server']['metadata'].items():
                 metadata.append({'key': k, 'value': v})
 
-        personality = env['server'].get('personality', [])
-        injected_files = self._get_injected_files(personality)
+        personality = env['server'].get('personality')
+        injected_files = []
+        if personality:
+            injected_files = self._get_injected_files(personality)
 
         flavor_id = self._flavor_id_from_req_data(env)
         try:
@@ -189,6 +192,7 @@ class Controller(wsgi.Controller):
         underlying compute service.
         """
         injected_files = []
+
         for item in personality:
             try:
                 path = item['path']
@@ -513,6 +517,7 @@ class Controller(wsgi.Controller):
 
         return kernel_id, ramdisk_id
 
+
 class ControllerV10(Controller):
     def _image_id_from_req_data(self, data):
         return data['server']['imageId']
diff --git a/nova/api/openstack/users.py b/nova/api/openstack/users.py
index ebd0f4512..d3ab3d553 100644
--- a/nova/api/openstack/users.py
+++ b/nova/api/openstack/users.py
@@ -13,13 +13,14 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import common
+from webob import exc
 
 from nova import exception
 from nova import flags
 from nova import log as logging
 from nova import wsgi
-
+from nova.api.openstack import common
+from nova.api.openstack import faults
 from nova.auth import manager
 
 FLAGS = flags.FLAGS
@@ -63,7 +64,17 @@ class Controller(wsgi.Controller):
 
     def show(self, req, id):
         """Return data about the given user id"""
-        user = self.manager.get_user(id)
+
+        #NOTE(justinsb): The drivers are a little inconsistent in how they
+        #  deal with "NotFound" - some throw, some return None.
+        try:
+            user = self.manager.get_user(id)
+        except exception.NotFound:
+            user = None
+
+        if user is None:
+            raise faults.Fault(exc.HTTPNotFound())
+
         return dict(user=_translate_keys(user))
 
     def delete(self, req, id):
diff --git a/nova/api/openstack/views/servers.py b/nova/api/openstack/views/servers.py
index 8d47ac757..f93435198 100644
--- a/nova/api/openstack/views/servers.py
+++ b/nova/api/openstack/views/servers.py
@@ -16,7 +16,10 @@
 #    under the License.
 
 import hashlib
+
 from nova.compute import power_state
+import nova.compute
+import nova.context
 from nova.api.openstack import common
 from nova.api.openstack.views import addresses as addresses_view
 from nova.api.openstack.views import flavors as flavors_view
@@ -25,28 +28,29 @@ from nova import utils
 
 
 class ViewBuilder(object):
-    '''
-    Models a server response as a python dictionary.
+    """Model a server response as a python dictionary.
+
+    Public methods: build
     Abstract methods: _build_image, _build_flavor
-    '''
+
+    """
 
     def __init__(self, addresses_builder):
         self.addresses_builder = addresses_builder
 
     def build(self, inst, is_detail):
-        """
-        Coerces into dictionary format, mapping everything to
-        Rackspace-like attributes for return
-        """
+        """Return a dict that represenst a server."""
         if is_detail:
             return self._build_detail(inst)
         else:
             return self._build_simple(inst)
 
     def _build_simple(self, inst):
-            return dict(server=dict(id=inst['id'], name=inst['display_name']))
+        """Return a simple model of a server."""
+        return dict(server=dict(id=inst['id'], name=inst['display_name']))
 
     def _build_detail(self, inst):
+        """Returns a detailed model of a server."""
         power_mapping = {
             None: 'build',
             power_state.NOSTATE: 'build',
@@ -58,18 +62,22 @@ class ViewBuilder(object):
             power_state.SHUTOFF: 'active',
             power_state.CRASHED: 'error',
             power_state.FAILED: 'error'}
-        inst_dict = {}
 
-        inst_dict['id'] = int(inst['id'])
-        inst_dict['name'] = inst['display_name']
-        inst_dict['status'] = power_mapping[inst.get('state')]
-        inst_dict['addresses'] = self.addresses_builder.build(inst)
+        inst_dict = {
+            'id': int(inst['id']),
+            'name': inst['display_name'],
+            'addresses': self.addresses_builder.build(inst),
+            'status': power_mapping[inst.get('state')]}
+
+        ctxt = nova.context.get_admin_context()
+        compute_api = nova.compute.API()
+        if compute_api.has_finished_migration(ctxt, inst['id']):
+            inst_dict['status'] = 'resize-confirm'
 
         # Return the metadata as a dictionary
         metadata = {}
-        if 'metadata' in inst:
-            for item in inst['metadata']:
-                metadata[item['key']] = item['value']
+        for item in inst.get('metadata', []):
+            metadata[item['key']] = item['value']
         inst_dict['metadata'] = metadata
 
         inst_dict['hostId'] = ''
@@ -82,36 +90,36 @@ class ViewBuilder(object):
         return dict(server=inst_dict)
 
     def _build_image(self, response, inst):
+        """Return the image sub-resource of a server."""
         raise NotImplementedError()
 
     def _build_flavor(self, response, inst):
+        """Return the flavor sub-resource of a server."""
         raise NotImplementedError()
 
 
 class ViewBuilderV10(ViewBuilder):
+    """Model an Openstack API V1.0 server response."""
+
     def _build_image(self, response, inst):
-        if inst.get('image_id') != None:
-            response['imageId'] = inst['image_id']
+        response['imageId'] = inst['image_id']
 
     def _build_flavor(self, response, inst):
-        if inst.get('instance_type') != None:
-            response['flavorId'] = inst['instance_type']
+        response['flavorId'] = inst['instance_type']
 
 
 class ViewBuilderV11(ViewBuilder):
+    """Model an Openstack API V1.0 server response."""
+
     def __init__(self, addresses_builder, flavor_builder, image_builder):
         ViewBuilder.__init__(self, addresses_builder)
         self.flavor_builder = flavor_builder
         self.image_builder = image_builder
 
     def _build_image(self, response, inst):
-        if inst.get('image_id') == None:
-            return
         image_id = inst["image_id"]
         response["imageRef"] = self.image_builder.generate_href(image_id)
 
     def _build_flavor(self, response, inst):
-        if inst.get('instance_type') == None:
-            return
         flavor_id = inst["instance_type"]
         response["flavorRef"] = self.flavor_builder.generate_href(flavor_id)