refactor: upload data unification, less permissions and less endpoints (#31959)

superset/commands/database/uploaders/base.py

@@ -36,6 +36,7 @@ from superset.connectors.sqla.models import SqlaTable
 from superset.daos.database import DatabaseDAO
 from superset.models.core import Database
 from superset.sql_parse import Table
+from superset.utils.backports import StrEnum
 from superset.utils.core import get_user
 from superset.utils.decorators import on_error, transaction
 from superset.views.database.validators import schema_allows_file_upload
@@ -45,6 +46,12 @@ logger = logging.getLogger(__name__)
 READ_CHUNK_SIZE = 1000
 
 
+class UploadFileType(StrEnum):
+    CSV = "csv"
+    EXCEL = "excel"
+    COLUMNAR = "columnar"
+
+
 class ReaderOptions(TypedDict, total=False):
     already_exists: str
     index_label: str