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# Licensed under the Apache License, Version 2.0 (the "License"). You
# may not use this file except in compliance with the License. A copy of
# the License is located at
#
#     http://aws.amazon.com/apache2.0/
#
# or in the "license" file accompanying this file. This file is
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"""Configuration for the SageMaker Training Compiler."""
from __future__ import absolute_import
import logging
from packaging.specifiers import SpecifierSet
from packaging.version import Version

from sagemaker.training_compiler.config import TrainingCompilerConfig as BaseConfig

logger = logging.getLogger(__name__)


class TrainingCompilerConfig(BaseConfig):
    """The SageMaker Training Compiler configuration class."""

    SUPPORTED_INSTANCE_CLASS_PREFIXES = ["p3", "p3dn", "g4dn", "p4d", "g5"]
    MIN_SUPPORTED_VERSION = "2.9"
    MAX_SUPPORTED_VERSION = "2.11"

    def __init__(self, enabled=True, debug=False):
        """This class initializes a ``TrainingCompilerConfig`` instance.

        `Amazon SageMaker Training Compiler
        <https://docs.aws.amazon.com/sagemaker/latest/dg/training-compiler.html>`_
        is a feature of SageMaker Training
        and speeds up training jobs by optimizing model execution graphs.

        You can compile TensorFlow models
        by passing the object of this configuration class to the ``compiler_config``
        parameter of the :class:`~sagemaker.tensorflow.TensorFlow`
        estimator.

        Args:
            enabled (bool): Optional. Switch to enable SageMaker Training Compiler.
                The default is ``True``.
            debug (bool): Optional. Whether to dump detailed logs for debugging.
                This comes with a potential performance slowdown.
                The default is ``False``.

        **Example**: The following code shows the basic usage of the
        :class:`sagemaker.tensorflow.TrainingCompilerConfig()` class
        to run a TensorFlow training job with the compiler.

        .. code-block:: python

            from sagemaker.tensorflow import TensorFlow, TrainingCompilerConfig

            tensorflow_estimator=TensorFlow(
                ...
                compiler_config=TrainingCompilerConfig()
            )

        .. seealso::

            For more information about how to enable SageMaker Training Compiler
            for various training settings such as using TensorFlow-based models,
            PyTorch-based models, and distributed training,
            see `Enable SageMaker Training Compiler
            <https://docs.aws.amazon.com/sagemaker/latest/dg/training-compiler-enable.html>`_
            in the `Amazon SageMaker Training Compiler developer guide
            <https://docs.aws.amazon.com/sagemaker/latest/dg/training-compiler.html>`_.

        """

        super(TrainingCompilerConfig, self).__init__(enabled=enabled, debug=debug)

    @classmethod
    def validate(cls, estimator):
        """Checks if SageMaker Training Compiler is configured correctly.

        Args:
            estimator (:class:`sagemaker.tensorflow.estimator.TensorFlow`): A estimator object
                If SageMaker Training Compiler is enabled, it will validate whether
                the estimator is configured to be compatible with Training Compiler.

        Raises:
            ValueError: Raised if the requested configuration is not compatible
                        with SageMaker Training Compiler.
        """

        super(TrainingCompilerConfig, cls).validate(estimator)

        if estimator.framework_version:
            if Version(estimator.framework_version) not in SpecifierSet(
                f">= {cls.MIN_SUPPORTED_VERSION}", f"<= {cls.MAX_SUPPORTED_VERSION}"
            ):
                error_helper_string = (
                    "SageMaker Training Compiler only supports TensorFlow version "
                    "between {} to {} but received {}"
                )
                error_helper_string = error_helper_string.format(
                    cls.MIN_SUPPORTED_VERSION,
                    cls.MAX_SUPPORTED_VERSION,
                    estimator.framework_version,
                )
                raise ValueError(error_helper_string)

        if estimator.distribution and "multi_worker_mirrored_strategy" in estimator.distribution:
            mwms_enabled = estimator.distribution.get("multi_worker_mirrored_strategy").get(
                "enabled", False
            )
            if mwms_enabled:
                raise ValueError(
                    "Multi Worker Mirrored Strategy distributed training configuration "
                    "is currently not compatible with SageMaker Training Compiler."
                )