def list_column_families(self, timeout_seconds=None):
"""Check if this table exists.
:type timeout_seconds: int
:param timeout_seconds: Number of seconds for request time-out.
If not passed, defaults to value set on table.
:rtype: dictionary with string as keys and
:class:`.column_family.ColumnFamily` as values
:returns: List of column families attached to this table.
:raises: :class:`ValueError <exceptions.ValueError>` if the column
family name from the response does not agree with the computed
name from the column family ID.
"""
request_pb = messages_pb2.GetTableRequest(name=self.name)
timeout_seconds = timeout_seconds or self.timeout_seconds
response = self.client.table_stub.GetTable.async(request_pb,
timeout_seconds)
# We expect a `._generated.bigtable_table_data_pb2.Table`
table_pb = response.result()
result = {}
for column_family_id, value_pb in table_pb.column_families.items():
gc_rule = _gc_rule_from_pb(value_pb.gc_rule)
column_family = self.column_family(column_family_id,
gc_rule=gc_rule)
if column_family.name != value_pb.name:
raise ValueError('Column family name %s does not agree with '
'name from request: %s.' % (
column_family.name, value_pb.name))
result[column_family_id] = column_family
return result
def _callFUT(self, gc_rule_pb):
from gcloud_bigtable.column_family import _gc_rule_from_pb
return _gc_rule_from_pb(gc_rule_pb)
