# Copyright 2017 The PyAthena authors
#
# Licensed under the MIT License.
# See LICENSE or https://opensource.org/licenses/MIT.
#
# SPDX-License-Identifier: MIT
"""Native asyncio cursor that reads Athena CSV query results through ``AioS3FileSystem``."""
from __future__ import annotations
import asyncio
import logging
from collections.abc import Callable
from typing import Any
from pyathena.aio.common import WithAsyncFetch
from pyathena.common import CursorIterator
from pyathena.error import OperationalError
from pyathena.filesystem.s3_async import AioS3FileSystem
from pyathena.model import AthenaQueryExecution
from pyathena.options import ExecuteOptions
from pyathena.s3fs.converter import DefaultS3FSTypeConverter
from pyathena.s3fs.result_set import AthenaS3FSResultSet, CSVReaderType
from pyathena.util import override
_logger = logging.getLogger(__name__)
[docs]
class AioS3FSCursor(WithAsyncFetch):
"""Native asyncio cursor that reads CSV results via AioS3FileSystem.
Uses ``AioS3FileSystem`` for S3 operations, which replaces
``ThreadPoolExecutor`` parallelism with ``asyncio.gather`` +
``asyncio.to_thread``. Fetch operations are wrapped in
``asyncio.to_thread()`` because CSV reading is blocking I/O.
Example:
>>> async with await pyathena.aio_connect(...) as conn:
... cursor = conn.cursor(AioS3FSCursor)
... await cursor.execute("SELECT * FROM my_table")
... row = await cursor.fetchone()
"""
[docs]
def __init__(
self,
s3_staging_dir: str | None = None,
schema_name: str | None = None,
catalog_name: str | None = None,
work_group: str | None = None,
poll_interval: float = 1,
encryption_option: str | None = None,
kms_key: str | None = None,
kill_on_interrupt: bool = True,
result_reuse_enable: bool = False,
result_reuse_minutes: int = CursorIterator.DEFAULT_RESULT_REUSE_MINUTES,
csv_reader: CSVReaderType | None = None,
**kwargs,
) -> None:
"""Initialize an AioS3FSCursor.
Args:
s3_staging_dir: S3 location for query results.
schema_name: Default schema name.
catalog_name: Default catalog name.
work_group: Athena workgroup name.
poll_interval: Query status polling interval in seconds.
encryption_option: S3 encryption option for query results.
kms_key: KMS key for encrypting query results.
kill_on_interrupt: Cancel the query when the task is cancelled while
``execute()`` starts or waits for the query.
result_reuse_enable: Whether to enable Athena query result reuse.
result_reuse_minutes: Maximum age of a reused query result in minutes.
csv_reader: CSV reader class for parsing the result files. If None,
``AthenaCSVReader`` is used, which distinguishes NULL from empty
strings. ``DefaultCSVReader`` reads both as empty strings.
**kwargs: Other cursor arguments, such as ``connection`` and ``arraysize``,
passed to the parent ``__init__``.
"""
super().__init__(
s3_staging_dir=s3_staging_dir,
schema_name=schema_name,
catalog_name=catalog_name,
work_group=work_group,
poll_interval=poll_interval,
encryption_option=encryption_option,
kms_key=kms_key,
kill_on_interrupt=kill_on_interrupt,
result_reuse_enable=result_reuse_enable,
result_reuse_minutes=result_reuse_minutes,
**kwargs,
)
self._csv_reader = csv_reader
self._result_set: AthenaS3FSResultSet | None = None
[docs]
@staticmethod
@override
def get_default_converter(
unload: bool = False,
) -> DefaultS3FSTypeConverter:
"""Get the default type converter for S3FS cursor.
Args:
unload: Unused. S3FS cursor does not support UNLOAD operations.
Returns:
DefaultS3FSTypeConverter instance.
"""
return DefaultS3FSTypeConverter()
[docs]
@override
async def execute(
self,
operation: str,
parameters: dict[str, Any] | list[str] | None = None,
work_group: str | None = None,
s3_staging_dir: str | None = None,
cache_size: int | None = None,
cache_expiration_time: int | None = None,
result_reuse_enable: bool | None = None,
result_reuse_minutes: int | None = None,
paramstyle: str | None = None,
on_start_query_execution: Callable[[str], None] | None = None,
result_set_type_hints: dict[str | int, str] | None = None,
*,
options: ExecuteOptions | None = None,
**kwargs,
) -> AioS3FSCursor:
"""Execute a SQL query asynchronously via S3FileSystem CSV reader.
Args:
operation: SQL query string to execute.
parameters: Query parameters for parameterized queries.
work_group: Athena workgroup to use for this query.
s3_staging_dir: S3 location for query results.
cache_size: Number of queries to check for result caching.
cache_expiration_time: Cache expiration time in seconds.
result_reuse_enable: Enable Athena result reuse for this query.
result_reuse_minutes: Minutes to reuse cached results.
paramstyle: Parameter style ('qmark' or 'pyformat').
on_start_query_execution: Callback invoked with the query ID before ``execute()``
waits for the query: after the ``StartQueryExecution`` call, or after a
reusable query ID is found through ``cache_size``.
result_set_type_hints: Athena type signatures for complex-type columns,
keyed by column name (case-insensitive) or zero-based column index.
options: Shared execution options as an
:class:`~pyathena.options.ExecuteOptions` instance. Individual
keyword arguments take precedence over ``options`` fields.
**kwargs: Additional execution parameters.
Returns:
Self reference for method chaining.
"""
self._reset_state()
options = ExecuteOptions.resolve(
options,
work_group=work_group,
s3_staging_dir=s3_staging_dir,
cache_size=cache_size,
cache_expiration_time=cache_expiration_time,
result_reuse_enable=result_reuse_enable,
result_reuse_minutes=result_reuse_minutes,
paramstyle=paramstyle,
on_start_query_execution=on_start_query_execution,
result_set_type_hints=result_set_type_hints,
)
self.query_id = await self._execute(
operation,
parameters=parameters,
options=options,
)
# Call user callbacks immediately after start_query_execution
self._call_on_start_query_execution(self.query_id, options)
query_execution = await self._poll(self.query_id)
if query_execution.state == AthenaQueryExecution.STATE_SUCCEEDED:
self.result_set = await asyncio.to_thread(
AthenaS3FSResultSet,
connection=self._connection,
converter=self._converter,
query_execution=query_execution,
arraysize=self.arraysize,
retry_config=self._retry_config,
csv_reader=self._csv_reader,
filesystem_class=AioS3FileSystem,
result_set_type_hints=options.result_set_type_hints,
**kwargs,
)
else:
raise OperationalError(query_execution.state_change_reason)
return self