fix: validate CSV export cursors before writing

This commit is contained in:
Rami Abdelrazzaq 2026-09-13 13:15:08 -05:00
commit 6f064ce6ee
2 changed files with 10 additions and 13 deletions

View file

@ -1,5 +1,5 @@
import csv
from typing import Any, Iterable, Optional, Sequence, TextIO, Union
from typing import Any, Sequence, TextIO, Union
CsvDialect = Union[str, csv.Dialect]
@ -21,16 +21,11 @@ def rows_to_csv_file(
Additional keyword arguments are forwarded to ``csv.writer``.
"""
description: Union[Sequence[Sequence[Any]], None] = cursor.description
if description is None:
raise ValueError("Cursor does not have result columns")
writer = csv.writer(file, dialect=dialect, **writer_kwargs)
if header:
description: Optional[Sequence[Sequence[Any]]] = cursor.description
if description is None:
raise ValueError("Cursor does not have result columns")
writer.writerow([column[0] for column in description])
writer.writerows(_rows(cursor))
def _rows(cursor: Iterable[Sequence[Any]]) -> Iterable[Sequence[Any]]:
"""Keep row iteration lazy so large query results are streamed."""
for row in cursor:
yield row
writer.writerows(cursor)