def _get_quotas(self, context, resources, keys):
"""Get quotas.
A helper method which retrieves the quotas for the specific
resources identified by keys, and which apply to the current
context.
:param context: The request context, for access checks.
:param resources: A dictionary of the registered resources.
:param keys: A list of the desired quotas to retrieve.
"""
# Filter resources
desired = set(keys)
sub_resources = dict(
(k, v) for k, v in resources.items() if k in desired)
# Make sure we accounted for all of them...
if len(keys) != len(sub_resources):
unknown = desired - set(sub_resources.keys())
raise exceptions.QuotaResourceUnknown(unknown=sorted(unknown))
quotas = {}
for resource in sub_resources.values():
quotas[resource.name] = resource.default
return quotas
def limit_check(self, context, tenant_id, **values):
"""Check simple quota limits.
For limits--those quotas for which there is no usage
synchronization function--this method checks that a set of
proposed values are permitted by the limit restriction. The
values to check are given as keyword arguments, where the key
identifies the specific quota limit to check, and the value is
the proposed value.
This method will raise a QuotaResourceUnknown exception if a
given resource is unknown or if it is not a countable resource.
If any of the proposed values exceeds the respective quota defined
for the tenant, an OverQuota exception will be raised.
The exception will include a sorted list with the resources
which exceed the quota limit. Otherwise, the method returns nothing.
:param context: Request context
:param tenant_id: Tenant for which the quota limit is being checked
:param values: Dict specifying requested deltas for each resource
"""
# Verify that resources are managed by the quota engine
requested_resources = set(values.keys())
managed_resources = set([res for res in self._resources.keys()
if res in requested_resources])
# Make sure we accounted for all of them...
unknown_resources = requested_resources - managed_resources
if unknown_resources:
raise exceptions.QuotaResourceUnknown(
unknown=sorted(unknown_resources))
return self.get_driver().limit_check(context, tenant_id,
self._resources, values)
def make_reservation(self, context, tenant_id, deltas, plugin):
# Verify that resources are managed by the quota engine
# Ensure no value is less than zero
unders = [key for key, val in deltas.items() if val < 0]
if unders:
raise exceptions.InvalidQuotaValue(unders=sorted(unders))
requested_resources = set(deltas.keys())
all_resources = resource_registry.get_all_resources()
managed_resources = set([res for res in all_resources.keys()
if res in requested_resources])
# Make sure we accounted for all of them...
unknown_resources = requested_resources - managed_resources
if unknown_resources:
raise exceptions.QuotaResourceUnknown(
unknown=sorted(unknown_resources))
# FIXME(salv-orlando): There should be no reason for sending all the
# resource in the registry to the quota driver, but as other driver
# APIs request them, this will be sorted out with a different patch.
return self.get_driver().make_reservation(
context,
tenant_id,
all_resources,
deltas,
plugin)
def _get_quotas(self, context, tenant_id, resources, keys):
"""Retrieves the quotas for specific resources.
A helper method which retrieves the quotas for the specific
resources identified by keys, and which apply to the current
context.
:param context: The request context, for access checks.
:param tenant_id: the tenant_id to check quota.
:param resources: A dictionary of the registered resources.
:param keys: A list of the desired quotas to retrieve.
"""
desired = set(keys)
sub_resources = dict((k, v) for k, v in resources.items()
if k in desired)
# Make sure we accounted for all of them...
if len(keys) != len(sub_resources):
unknown = desired - set(sub_resources.keys())
raise exceptions.QuotaResourceUnknown(unknown=sorted(unknown))
# Grab and return the quotas (without usages)
quotas = DbQuotaDriver.get_tenant_quotas(
context, sub_resources, tenant_id)
return dict((k, v) for k, v in quotas.items())
def count(self, context, resource, *args, **kwargs):
"""Count a resource.
For countable resources, invokes the count() function and
returns its result. Arguments following the context and
resource are passed directly to the count function declared by
the resource.
:param context: The request context, for access checks.
:param resource: The name of the resource, as a string.
"""
# Get the resource
res = self._resources.get(resource)
if not res or not hasattr(res, 'count'):
raise exceptions.QuotaResourceUnknown(unknown=[resource])
return res.count(context, *args, **kwargs)