Asynchronous List Transformations

flytekit/core/type_engine.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import asyncio
 import collections
 import copy
 import dataclasses
@@ -8,9 +9,11 @@
 import inspect
 import json as _json
 import mimetypes
+import os
 import textwrap
 import typing
 from abc import ABC, abstractmethod
+from concurrent.futures import ThreadPoolExecutor
 from functools import lru_cache
 from typing import Dict, NamedTuple, Optional, Type, cast
 
@@ -28,7 +31,7 @@
 from flytekit.core.context_manager import FlyteContext
 from flytekit.core.hash import HashMethod
 from flytekit.core.type_helpers import load_type_from_tag
-from flytekit.core.utils import timeit
+from flytekit.core.utils import coroutine, timeit
 from flytekit.exceptions import user as user_exceptions
 from flytekit.lazy_import.lazy_module import is_imported
 from flytekit.loggers import logger
@@ -1041,62 +1044,40 @@ def get_literal_type(self, t: Type[T]) -> Optional[LiteralType]:
         except Exception as e:
             raise ValueError(f"Type of Generic List type is not supported, {e}")
 
-    @staticmethod
-    def is_batchable(t: Type):
-        """
-        This function evaluates whether the provided type is batchable or not.
-        It returns True only if the type is either List or Annotated(List) and the List subtype is FlytePickle.
-        """
-        from flytekit.types.pickle import FlytePickle
-
-        if is_annotated(t):
-            return ListTransformer.is_batchable(get_args(t)[0])
-        if get_origin(t) is list:
-            subtype = get_args(t)[0]
-            if subtype == FlytePickle or (hasattr(subtype, "__origin__") and subtype.__origin__ == FlytePickle):
-                return True
-        return False
-
-    def to_literal(self, ctx: FlyteContext, python_val: T, python_type: Type[T], expected: LiteralType) -> Literal:
+    @timeit("ListTransformer: to_python_value")
+    @coroutine
+    async def to_literal(
+        self, ctx: FlyteContext, python_val: T, python_type: Type[T], expected: LiteralType
+    ) -> Literal:
         if type(python_val) != list:
             raise TypeTransformerFailedError("Expected a list")
 
-        if ListTransformer.is_batchable(python_type):
-            from flytekit.types.pickle.pickle import BatchSize, FlytePickle
-
-            batch_size = len(python_val)  # default batch size
-            # parse annotated to get the number of items saved in a pickle file.
-            if is_annotated(python_type):
-                for annotation in get_args(python_type)[1:]:
-                    if isinstance(annotation, BatchSize):
-                        batch_size = annotation.val
-                        break
-            if batch_size > 0:
-                lit_list = [TypeEngine.to_literal(ctx, python_val[i : i + batch_size], FlytePickle, expected.collection_type) for i in range(0, len(python_val), batch_size)]  # type: ignore
-            else:
-                lit_list = []
-        else:
+        # Set maximum number of threads to the number of processors on the machine, multiplied by 5 since it is  I/O bound task
+        # limit it to 32 to avoid consuming surprisingly large resource on many core machine.
+        with ThreadPoolExecutor(max_workers=min(32, (os.cpu_count() or 1) * 5)) as pool:
             t = self.get_sub_type(python_type)
-            lit_list = [TypeEngine.to_literal(ctx, x, t, expected.collection_type) for x in python_val]  # type: ignore
+            loop = asyncio.get_running_loop()
+            lit_future_list = [
+                loop.run_in_executor(pool, TypeEngine.to_literal, ctx, x, t, expected.collection_type) for x in python_val  # type: ignore
+            ]
+        lit_list = await asyncio.gather(*lit_future_list)
         return Literal(collection=LiteralCollection(literals=lit_list))
 
-    def to_python_value(self, ctx: FlyteContext, lv: Literal, expected_python_type: Type[T]) -> typing.List[typing.Any]:  # type: ignore
+    @timeit("ListTransformer: to_python_value")
+    @coroutine
+    async def to_python_value(self, ctx: FlyteContext, lv: Literal, expected_python_type: Type[T]) -> typing.List[typing.Any]:  # type: ignore
         try:
             lits = lv.collection.literals
         except AttributeError:
             raise TypeTransformerFailedError()
-        if self.is_batchable(expected_python_type):
-            from flytekit.types.pickle import FlytePickle
-
-            batch_list = [TypeEngine.to_python_value(ctx, batch, FlytePickle) for batch in lits]
-            if len(batch_list) > 0 and type(batch_list[0]) is list:
-                # Make it have backward compatibility. The upstream task may use old version of Flytekit that
-                # won't merge the elements in the list. Therefore, we should check if the batch_list[0] is the list first.
-                return [item for batch in batch_list for item in batch]
-            return batch_list
-        else:
+
+        # Set maximum number of threads to the number of processors on the machine, multiplied by 5 since it is  I/O bound task
+        # limit it to 32 to avoid consuming surprisingly large resource on many core machine.
+        with ThreadPoolExecutor(max_workers=min(32, (os.cpu_count() or 1) * 5)) as pool:
             st = self.get_sub_type(expected_python_type)
-            return [TypeEngine.to_python_value(ctx, x, st) for x in lits]
+            loop = asyncio.get_running_loop()
+            val_future_list = [loop.run_in_executor(pool, TypeEngine.to_python_value, ctx, x, st) for x in lits]
+        return await asyncio.gather(*val_future_list)
 
     def guess_python_type(self, literal_type: LiteralType) -> list:  # type: ignore
         if literal_type.collection_type:

flytekit/core/utils.py

@@ -1,3 +1,4 @@
+import asyncio
 import datetime
 import os as _os
 import shutil as _shutil
@@ -331,3 +332,11 @@ def __exit__(self, exc_type, exc_val, exc_tb):
                 end_process_time - self._start_process_time,
             )
         )
+
+
+def coroutine(func: Callable):
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        return asyncio.run(func(*args, **kwargs))
+
+    return wrapper

flytekit/types/pickle/__init__.py

@@ -9,4 +9,4 @@
    FlytePickle
 """
 
-from .pickle import BatchSize, FlytePickle
+from .pickle import FlytePickle

flytekit/types/pickle/pickle.py

@@ -13,19 +13,6 @@
 T = typing.TypeVar("T")
 
 
-class BatchSize:
-    """
-    Flyte-specific object used to wrap the hash function for a specific type
-    """
-
-    def __init__(self, val: int):
-        self._val = val
-
-    @property
-    def val(self) -> int:
-        return self._val
-
-
 class FlytePickle(typing.Generic[T]):
     """
     This type is only used by flytekit internally. User should not use this type.

tests/flytekit/unit/core/test_flyte_pickle.py

@@ -14,7 +14,7 @@
 from flytekit.models.literals import BlobMetadata
 from flytekit.models.types import LiteralType
 from flytekit.tools.translator import get_serializable
-from flytekit.types.pickle.pickle import BatchSize, FlytePickle, FlytePickleTransformer
+from flytekit.types.pickle.pickle import FlytePickle, FlytePickleTransformer
 
 default_img = Image(name="default", fqn="test", tag="tag")
 serialization_settings = flytekit.configuration.SerializationSettings(
@@ -57,11 +57,6 @@ def test_get_literal_type():
     assert lt == expected_lt
 
 
-def test_batch_size():
-    bs = BatchSize(5)
-    assert bs.val == 5
-
-
 def test_nested():
     class Foo(object):
         def __init__(self, number: int):

tests/flytekit/unit/core/test_promise.py

@@ -3,7 +3,6 @@
 
 import pytest
 from dataclasses_json import dataclass_json
-from typing_extensions import Annotated
 
 from flytekit import LaunchPlan, task, workflow
 from flytekit.core import context_manager
@@ -15,7 +14,6 @@
     translate_inputs_to_literals,
 )
 from flytekit.exceptions.user import FlyteAssertion
-from flytekit.types.pickle.pickle import BatchSize
 
 
 def test_create_and_link_node():
@@ -101,11 +99,11 @@ class MyDataclass(object):
 
 @pytest.mark.parametrize(
     "input",
-    [2.0, MyDataclass(i=1, a=["h", "e"]), [1, 2, 3], ["foo"] * 5],
+    [2.0, MyDataclass(i=1, a=["h", "e"]), [1, 2, 3]],
 )
 def test_translate_inputs_to_literals(input):
     @task
-    def t1(a: typing.Union[float, MyDataclass, Annotated[typing.List[typing.Any], BatchSize(2)]]):
+    def t1(a: typing.Union[float, typing.List[int], MyDataclass]):
         print(a)
 
     ctx = context_manager.FlyteContext.current_context()

tests/flytekit/unit/core/test_type_engine.py

@@ -20,7 +20,7 @@
 from marshmallow_enum import LoadDumpOptions
 from marshmallow_jsonschema import JSONSchema
 from pandas._testing import assert_frame_equal
-from typing_extensions import Annotated, get_args, get_origin
+from typing_extensions import Annotated, get_args
 
 from flytekit import kwtypes
 from flytekit.core.annotation import FlyteAnnotation
@@ -55,7 +55,7 @@
 from flytekit.types.file import FileExt, JPEGImageFile
 from flytekit.types.file.file import FlyteFile, FlyteFilePathTransformer, noop
 from flytekit.types.pickle import FlytePickle
-from flytekit.types.pickle.pickle import BatchSize, FlytePickleTransformer
+from flytekit.types.pickle.pickle import FlytePickleTransformer
 from flytekit.types.schema import FlyteSchema
 from flytekit.types.schema.types_pandas import PandasDataFrameTransformer
 from flytekit.types.structured.structured_dataset import StructuredDataset
@@ -1636,70 +1636,6 @@ def test_file_ext_with_flyte_file_wrong_type():
     assert str(e.value) == "Underlying type of File Extension must be of type <str>"
 
 
-def test_is_batchable():
-    assert ListTransformer.is_batchable(typing.List[int]) is False
-    assert ListTransformer.is_batchable(typing.List[str]) is False
-    assert ListTransformer.is_batchable(typing.List[typing.Dict]) is False
-    assert ListTransformer.is_batchable(typing.List[typing.Dict[str, FlytePickle]]) is False
-    assert ListTransformer.is_batchable(typing.List[typing.List[FlytePickle]]) is False
-
-    assert ListTransformer.is_batchable(typing.List[FlytePickle]) is True
-    assert ListTransformer.is_batchable(Annotated[typing.List[FlytePickle], BatchSize(3)]) is True
-    assert (
-        ListTransformer.is_batchable(Annotated[typing.List[FlytePickle], HashMethod(function=str), BatchSize(3)])
-        is True
-    )
-
-
-@pytest.mark.parametrize(
-    "python_val, python_type, expected_list_length",
-    [
-        # Case 1: List of FlytePickle objects with default batch size.
-        # (By default, the batch_size is set to the length of the whole list.)
-        # After converting to literal, the result will be [batched_FlytePickle(5 items)].
-        # Therefore, the expected list length is [1].
-        ([{"foo"}] * 5, typing.List[FlytePickle], [1]),
-        # Case 2: List of FlytePickle objects with batch size 2.
-        # After converting to literal, the result will be
-        # [batched_FlytePickle(2 items), batched_FlytePickle(2 items), batched_FlytePickle(1 item)].
-        # Therefore, the expected list length is [3].
-        (["foo"] * 5, Annotated[typing.List[FlytePickle], HashMethod(function=str), BatchSize(2)], [3]),
-        # Case 3: Nested list of FlytePickle objects with batch size 2.
-        # After converting to literal, the result will be
-        # [[batched_FlytePickle(3 items)], [batched_FlytePickle(3 items)]]
-        # Therefore, the expected list length is [2, 1] (the length of the outer list remains the same, the inner list is batched).
-        ([["foo", "foo", "foo"]] * 2, typing.List[Annotated[typing.List[FlytePickle], BatchSize(3)]], [2, 1]),
-        # Case 4: Empty list
-        ([[], typing.List[FlytePickle], []]),
-    ],
-)
-def test_batch_pickle_list(python_val, python_type, expected_list_length):
-    ctx = FlyteContext.current_context()
-    expected = TypeEngine.to_literal_type(python_type)
-    lv = TypeEngine.to_literal(ctx, python_val, python_type, expected)
-
-    tmp_lv = lv
-    for length in expected_list_length:
-        # Check that after converting to literal, the length of the literal list is equal to:
-        # - the length of the original list divided by the batch size if not nested
-        # - the length of the original list if it contains a nested list
-        assert len(tmp_lv.collection.literals) == length
-        tmp_lv = tmp_lv.collection.literals[0]
-
-    pv = TypeEngine.to_python_value(ctx, lv, python_type)
-    # Check that after converting literal to Python value, the result is equal to the original python values.
-    assert pv == python_val
-    if get_origin(python_type) is Annotated:
-        pv = TypeEngine.to_python_value(ctx, lv, get_args(python_type)[0])
-        # Remove the annotation and check that after converting to Python value, the result is equal
-        # to the original input values. This is used to simulate the following case:
-        # @workflow
-        # def wf():
-        #     data = task0()  # task0() -> Annotated[typing.List[FlytePickle], BatchSize(2)]
-        #     task1(data=data)  # task1(data: typing.List[FlytePickle])
-        assert pv == python_val
-
-
 @pytest.mark.parametrize(
     "t,expected",
     [