Add support for allocations in placement API

A new endpoint supporting PUT and DELETE methods with a path
of /allocations/{consumer_id} calls set_allocations and
delete_allocations to set or delete allocations for one or more
resource classes on one or more resource providers.

An example JSON body in PUT request takes the following form:

    {"allocations": [
      {
        "resource_provider": {
            "uuid": "d4b87fe1-30ca-4a65-8947-dfa3d85f10be"
        },
        "resources": {
            "MEMORY_MB": 64,
            "VCPU": 2
        }
      },
      {
        "resource_provider": {
            "uuid": "3cbe1001-bba9-4ef6-ae9c-feac1c3f9626"
        },
        "resources": {
            "DISK_GB": 28
        }
      }
    ]}

The body is validated against the JSON schema defined in the
ALLOCATION_SCHEMA constant.

The API code calls create_all and delete_all on the AllocationList
object. create_all() allows an existing allocation to be replaced.

Change-Id: Ic1e90636bad44b7dc76b45c5f93c67f3fe3297f7
Partially-Implements: blueprint generic-resource-pools

nova/api/openstack/placement/handler.py

@@ -28,6 +28,7 @@ import webob
 
 from oslo_log import log as logging
 
+from nova.api.openstack.placement.handlers import allocation
 from nova.api.openstack.placement.handlers import inventory
 from nova.api.openstack.placement.handlers import resource_provider
 from nova.api.openstack.placement.handlers import root
@@ -69,6 +70,10 @@ ROUTE_DECLARATIONS = {
     '/resource_providers/{uuid}/usages': {
         'GET': usage.list_usages
     },
+    '/allocations/{consumer_uuid}': {
+        'PUT': allocation.set_allocations,
+        'DELETE': allocation.delete_allocations,
+    },
 }
 
 

nova/api/openstack/placement/handlers/allocation.py

@@ -0,0 +1,156 @@
+#    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.
+"""Placement API handlers for setting and deleting allocations."""
+
+import jsonschema
+from oslo_serialization import jsonutils
+import webob
+
+from nova.api.openstack.placement import util
+from nova import exception
+from nova import objects
+
+
+ALLOCATION_SCHEMA = {
+    "type": "object",
+    "properties": {
+        "allocations": {
+            "type": "array",
+            "items": {
+                "type": "object",
+                "properties": {
+                    "resource_provider": {
+                        "type": "object",
+                        "properties": {
+                            "uuid": {
+                                "type": "string",
+                                "format": "uuid"
+                            }
+                        },
+                        "additionalProperties": False,
+                        "required": ["uuid"]
+                    },
+                    "resources": {
+                        "type": "object",
+                        "patternProperties": {
+                            "^[0-9A-Z_]+$": {
+                                "type": "integer"
+                            }
+                        },
+                        "additionalProperties": False
+                    }
+                },
+                "required": [
+                    "resource_provider",
+                    "resources"
+                ],
+                "additionalProperties": False
+            }
+        }
+    },
+    "required": ["allocations"],
+    "additionalProperties": False
+}
+
+
+def _extract_allocations(body, schema):
+    """Extract allocation data from a JSON body."""
+    try:
+        data = jsonutils.loads(body)
+    except ValueError as exc:
+        raise webob.exc.HTTPBadRequest(
+            'Malformed JSON: %s' % exc,
+            json_formatter=util.json_error_formatter)
+    try:
+        jsonschema.validate(data, schema,
+                            format_checker=jsonschema.FormatChecker())
+    except jsonschema.ValidationError as exc:
+        raise webob.exc.HTTPBadRequest(
+            'JSON does not validate: %s' % exc,
+            json_formatter=util.json_error_formatter)
+    return data
+
+
+@webob.dec.wsgify
+@util.require_content('application/json')
+def set_allocations(req):
+    context = req.environ['placement.context']
+    consumer_uuid = util.wsgi_path_item(req.environ, 'consumer_uuid')
+    data = _extract_allocations(req.body, ALLOCATION_SCHEMA)
+    allocation_data = data['allocations']
+
+    # If the body includes an allocation for a resource provider
+    # that does not exist, raise a 400.
+    allocation_objects = []
+    for allocation in allocation_data:
+        resource_provider_uuid = allocation['resource_provider']['uuid']
+
+        try:
+            resource_provider = objects.ResourceProvider.get_by_uuid(
+                context, resource_provider_uuid)
+        except exception.NotFound:
+            raise webob.exc.HTTPBadRequest(
+                "Allocation for resource provider '%s' "
+                "that does not exist." % resource_provider_uuid,
+                json_formatter=util.json_error_formatter)
+
+        resources = allocation['resources']
+        for resource_class in resources:
+            try:
+                allocation = objects.Allocation(
+                    resource_provider=resource_provider,
+                    consumer_id=consumer_uuid,
+                    resource_class=resource_class,
+                    used=resources[resource_class])
+            except ValueError as exc:
+                raise webob.exc.HTTPBadRequest(
+                    "Allocation of class '%s' for "
+                    "resource provider '%s' invalid: "
+                    "%s" % (resource_class, resource_provider_uuid, exc))
+            allocation_objects.append(allocation)
+
+    allocations = objects.AllocationList(context, objects=allocation_objects)
+    try:
+        allocations.create_all()
+    # InvalidInventory is a parent for several exceptions that
+    # indicate either that Inventory is not present, or that
+    # capacity limits have been exceeded.
+    except exception.InvalidInventory as exc:
+        raise webob.exc.HTTPConflict(
+            'Unable to allocate inventory: %s' % exc,
+            json_formatter=util.json_error_formatter)
+    except exception.ConcurrentUpdateDetected as exc:
+        raise webob.exc.HTTPConflict(
+            'Inventory changed while attempting to allocate: %s' % exc,
+            json_formatter=util.json_error_formatter)
+
+    req.response.status = 204
+    req.response.content_type = None
+    return req.response
+
+
+@webob.dec.wsgify
+def delete_allocations(req):
+    context = req.environ['placement.context']
+    consumer_uuid = util.wsgi_path_item(req.environ, 'consumer_uuid')
+
+    allocations = objects.AllocationList.get_all_by_consumer_id(
+        context, consumer_uuid)
+    if not allocations:
+        raise webob.exc.HTTPNotFound(
+            "No allocations for consumer '%s'" % consumer_uuid,
+            json_formatter=util.json_error_formatter)
+    allocations.delete_all()
+
+    req.response.status = 204
+    req.response.content_type = None
+    return req.response

nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml

@@ -0,0 +1,202 @@
+# Tests of allocations API
+#
+# TODO(cdent): Where in the process is the consumer id being
+# validated?
+
+
+fixtures:
+    - APIFixture
+
+defaults:
+    request_headers:
+        x-auth-token: admin
+        accept: application/json
+
+tests:
+
+- name: get allocations no consumer is 404
+  GET: /allocations
+  status: 404
+
+- name: get allocations is 405
+  GET: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  status: 405
+  response_headers:
+      allow: /(PUT, DELETE|DELETE, PUT)/
+
+- name: put an allocation no resource provider
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resources:
+              DISK_GB: 10
+  status: 400
+
+- name: create the resource provider
+  POST: /resource_providers
+  request_headers:
+      content-type: application/json
+  data:
+      name: $ENVIRON['RP_NAME']
+      uuid: $ENVIRON['RP_UUID']
+  status: 201
+
+- name: put an allocation no data
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  status: 400
+
+- name: put an allocation violate schema
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                cow: 10
+  status: 400
+
+- name: put an allocation no inventory
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 10
+  status: 409
+
+- name: post some inventory
+  POST: /resource_providers/$ENVIRON['RP_UUID']/inventories
+  request_headers:
+      content-type: application/json
+  data:
+      resource_class: DISK_GB
+      total: 2048
+      min_unit: 10
+      max_unit: 1024
+  status: 201
+
+- name: put an allocation
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 10
+  status: 204
+
+- name: put an allocation different consumer
+  PUT: /allocations/39715579-2167-4c63-8247-301311cc6703
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 10
+  status: 204
+
+- name: check usages after another 10
+  GET: /resource_providers/$ENVIRON['RP_UUID']/usages
+  response_json_paths:
+      $.usages.DISK_GB: 20
+
+# NOTE(cdent): Contravening the spec, we decided that it is
+# important to be able to update an existing allocation, so this
+# should work but it is important to check the usage.
+- name: put allocation again
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 12
+  status: 204
+
+- name: check usages after 12
+  GET: /resource_providers/$ENVIRON['RP_UUID']/usages
+  response_json_paths:
+      $.usages.DISK_GB: 22
+
+- name: put allocation bad resource class
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                COWS: 12
+  status: 400
+  response_strings:
+      - Field value COWS is invalid
+
+- name: delete allocation
+  DELETE: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  status: 204
+
+- name: delete allocation again
+  DELETE: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  status: 404
+
+- name: delete allocation of unknown consumer id
+  DELETE: /allocations/da78521f-bf7e-4e6e-9901-3f79bd94d55d
+  status: 404
+
+- name: redo an allocation
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 10
+  status: 204
+
+- name: add other inventory
+  POST: /resource_providers/$ENVIRON['RP_UUID']/inventories
+  request_headers:
+      content-type: application/json
+  data:
+      resource_class: VCPU
+      total: 32
+      min_unit: 1
+      max_unit: 8
+  status: 201
+
+- name: multiple allocations 
+  PUT: /allocations/833f0885-f78c-4788-bb2b-3607b0656be7
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 20
+                VCPU: 4
+  status: 204
+
+- name: check usages
+  GET: /resource_providers/$ENVIRON['RP_UUID']/usages
+  response_json_paths:
+      $.resource_provider_generation: 7
+      $.usages.DISK_GB: 40