| from abc import ABCMeta, abstractproperty |
| from six import with_metaclass |
| |
| class UpdatingMetadataWrapperBase(with_metaclass(ABCMeta, object)): |
| @abstractproperty |
| def _wrapped(self): |
| pass |
| |
| def __getattr__(self, name): |
| return getattr(self._wrapped, name) |
| |
| def __getitem__(self, idx): |
| return self._wrapped[idx] |
| |
| |
| class UpdatingTableMetadataWrapper(UpdatingMetadataWrapperBase): |
| """ |
| A class that provides an interface to a table's metadata that is refreshed |
| on access. |
| """ |
| def __init__(self, cluster, ks_name, table_name, max_schema_agreement_wait=None): |
| self._cluster = cluster |
| self._ks_name = ks_name |
| self._table_name = table_name |
| self.max_schema_agreement_wait = max_schema_agreement_wait |
| |
| @property |
| def _wrapped(self): |
| self._cluster.refresh_table_metadata( |
| self._ks_name, |
| self._table_name, |
| max_schema_agreement_wait=self.max_schema_agreement_wait |
| ) |
| return self._cluster.metadata.keyspaces[self._ks_name].tables[self._table_name] |
| |
| def __repr__(self): |
| return '{cls_name}(cluster={cluster}, ks_name={ks_name}, table_name={table_name}, max_schema_agreement_wait={max_wait})'.format( |
| cls_name=self.__class__.__name__, |
| cluster=repr(self._cluster), |
| ks_name=self._ks_name, |
| table_name=self._table_name, |
| max_wait=self.max_schema_agreement_wait) |
| |
| |
| class UpdatingKeyspaceMetadataWrapper(UpdatingMetadataWrapperBase): |
| """ |
| A class that provides an interface to a keyspace's metadata that is |
| refreshed on access. |
| """ |
| def __init__(self, cluster, ks_name, max_schema_agreement_wait=None): |
| self._cluster = cluster |
| self._ks_name = ks_name |
| self.max_schema_agreement_wait = max_schema_agreement_wait |
| |
| @property |
| def _wrapped(self): |
| self._cluster.refresh_keyspace_metadata( |
| self._ks_name, |
| max_schema_agreement_wait=self.max_schema_agreement_wait |
| ) |
| return self._cluster.metadata.keyspaces[self._ks_name] |
| |
| def __repr__(self): |
| return '{cls_name}(cluster={cluster}, ks_name={ks_name}, max_schema_agreement_wait={max_wait})'.format( |
| cls_name=self.__class__.__name__, |
| cluster=repr(self._cluster), |
| ks_name=self._ks_name, |
| max_wait=self.max_schema_agreement_wait) |
| |
| |
| class UpdatingClusterMetadataWrapper(UpdatingMetadataWrapperBase): |
| """ |
| A class that provides an interface to a cluster's metadata that is |
| refreshed on access. |
| """ |
| def __init__(self, cluster, max_schema_agreement_wait=None): |
| """ |
| @param cluster The cassandra.cluster.Cluster object to wrap. |
| """ |
| self._cluster = cluster |
| self.max_schema_agreement_wait = max_schema_agreement_wait |
| |
| @property |
| def _wrapped(self): |
| self._cluster.refresh_schema_metadata(max_schema_agreement_wait=self.max_schema_agreement_wait) |
| return self._cluster.metadata |
| |
| def __repr__(self): |
| return '{cls_name}(cluster={cluster}, max_schema_agreement_wait={max_wait})'.format( |
| cls_name=self.__class__.__name__, |
| cluster=repr(self._cluster), |
| max_wait=self.max_schema_agreement_wait) |
