def get_physical_table_metadata(
database: Database,
table_name: str,
schema_name: Optional[str] = None,
) -> List[Dict[str, Any]]:
"""Use SQLAlchemy inspector to get table metadata"""
db_engine_spec = database.db_engine_spec
db_dialect = database.get_dialect()
# ensure empty schema
_schema_name = schema_name if schema_name else None
# Table does not exist or is not visible to a connection.
if not (database.has_table_by_name(table_name=table_name,
schema=_schema_name)
or database.has_view_by_name(view_name=table_name,
schema=_schema_name)):
raise NoSuchTableError
cols = database.get_columns(table_name, schema=_schema_name)
for col in cols:
try:
if isinstance(col["type"], TypeEngine):
db_type = db_engine_spec.column_datatype_to_string(
col["type"], db_dialect)
type_spec = db_engine_spec.get_column_spec(
db_type, db_extra=database.get_extra())
col.update({
"type":
db_type,
"type_generic":
type_spec.generic_type if type_spec else None,
"is_dttm":
type_spec.is_dttm if type_spec else None,
})
# Broad exception catch, because there are multiple possible exceptions
# from different drivers that fall outside CompileError
except Exception: # pylint: disable=broad-except
col.update({
"type": "UNKNOWN",
"type_generic": None,
"is_dttm": None,
})
return cols
def check_extra(self, database: Database) -> None: # pylint: disable=no-self-use
# this will check whether json.loads(extra) can succeed
try:
extra = database.get_extra()
except Exception as ex:
raise Exception(
_("Extra field cannot be decoded by JSON. %{msg}s",
msg=str(ex)))
# this will check whether 'metadata_params' is configured correctly
metadata_signature = inspect.signature(MetaData)
for key in extra.get("metadata_params", {}):
if key not in metadata_signature.parameters:
raise Exception(
_(
"The metadata_params in Extra field "
"is not configured correctly. The key "
"%{key}s is invalid.",
key=key,
))