def create(self):
if self.id is not None:
raise exception.ObjectActionError(action='create',
reason='already created')
if not self.name:
raise exception.ObjectActionError(action='create',
reason='name is required')
if self.name in orc.STANDARDS:
raise exception.ResourceClassExists(resource_class=self.name)
if not self.name.startswith(orc.CUSTOM_NAMESPACE):
raise exception.ObjectActionError(action='create',
reason='name must start with ' +
orc.CUSTOM_NAMESPACE)
updates = {}
for field in ['name', 'updated_at', 'created_at']:
value = getattr(self, field, None)
if value:
updates[field] = value
# There is the possibility of a race when adding resource classes, as
# the ID is generated locally. This loop catches that exception, and
# retries until either it succeeds, or a different exception is
# encountered.
retries = self.RESOURCE_CREATE_RETRY_COUNT
while retries:
retries -= 1
try:
rc = self._create_in_db(self._context, updates)
self._from_db_object(self._context, self, rc)
break
except db_exc.DBDuplicateEntry as e:
if 'id' in e.columns:
# Race condition for ID creation; try again
continue
# The duplication is on the other unique column, 'name'. So do
# not retry; raise the exception immediately.
raise exception.ResourceClassExists(resource_class=self.name)
else:
# We have no idea how common it will be in practice for the retry
# limit to be exceeded. We set it high in the hope that we never
# hit this point, but added this log message so we know that this
# specific situation occurred.
LOG.warning(
"Exceeded retry limit on ID generation while "
"creating ResourceClass %(name)s", {'name': self.name})
msg = "creating resource class %s" % self.name
raise exception.MaxDBRetriesExceeded(action=msg)
self._context.rc_cache.clear()
def _save(context, id, name, updates):
db_rc = context.session.query(
models.ResourceClass).filter_by(id=id).first()
db_rc.update(updates)
try:
db_rc.save(context.session)
except db_exc.DBDuplicateEntry:
raise exception.ResourceClassExists(resource_class=name)
def _save(context, name, updates):
update_list = ["rc.%s = '%s'" % (k, v) for k, v in updates.items()]
update_str = ", ".join(update_list)
query = """
MATCH (rc:RESOURCE_CLASS {name: '%s'})
WITH rc
SET %s
RETURN rc
""" % (name, update_str)
try:
result = context.tx.run(query).data()
except db.ClientError:
raise exception.ResourceClassExists(resource_class=name)