lightweight_python_functions_v2_pipeline.py

# Copyright 2021 The Kubeflow Authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Sample pipeline for passing data in KFP v2."""
from typing import Dict, List

from kfp import compiler
from kfp import dsl
from kfp.dsl import Input, InputPath, Output, OutputPath, Dataset, Model, component


@component
def preprocess(
    # An input parameter of type string.
    message: str,
    # Use Output[T] to get a metadata-rich handle to the output artifact
    # of type `Dataset`.
    output_dataset_one: Output[Dataset],
    # A locally accessible filepath for another output artifact of type
    # `Dataset`.
    output_dataset_two_path: OutputPath('Dataset'),
    # A locally accessible filepath for an output parameter of type string.
    output_parameter_path: OutputPath(str),
    # A locally accessible filepath for an output parameter of type bool.
    output_bool_parameter_path: OutputPath(bool),
    # A locally accessible filepath for an output parameter of type dict.
    output_dict_parameter_path: OutputPath(Dict[str, int]),
    # A locally accessible filepath for an output parameter of type list.
    output_list_parameter_path: OutputPath(List[str]),
):
    """Dummy preprocessing step."""

    # Use Dataset.path to access a local file path for writing.
    # One can also use Dataset.uri to access the actual URI file path.
    with open(output_dataset_one.path, 'w') as f:
        f.write(message)

    # OutputPath is used to just pass the local file path of the output artifact
    # to the function.
    with open(output_dataset_two_path, 'w') as f:
        f.write(message)

    with open(output_parameter_path, 'w') as f:
        f.write(message)

    with open(output_bool_parameter_path, 'w') as f:
        f.write(
            str(True))  # use either `str()` or `json.dumps()` for bool values.

    import json
    with open(output_dict_parameter_path, 'w') as f:
        f.write(json.dumps({'A': 1, 'B': 2}))

    with open(output_list_parameter_path, 'w') as f:
        f.write(json.dumps(['a', 'b', 'c']))


@component
def train(
    # Use InputPath to get a locally accessible path for the input artifact
    # of type `Dataset`.
    dataset_one_path: InputPath('Dataset'),
    # Use Input[T] to get a metadata-rich handle to the input artifact
    # of type `Dataset`.
    dataset_two: Input[Dataset],
    # An input parameter of type string.
    message: str,
    # Use Output[T] to get a metadata-rich handle to the output artifact
    # of type `Dataset`.
    model: Output[Model],
    # An input parameter of type bool.
    input_bool: bool,
    # An input parameter of type dict.
    input_dict: Dict[str, int],
    # An input parameter of type List[str].
    input_list: List[str],
    # An input parameter of type int with a default value.
    num_steps: int = 100,
):
    """Dummy Training step."""
    with open(dataset_one_path, 'r') as input_file:
        dataset_one_contents = input_file.read()

    with open(dataset_two.path, 'r') as input_file:
        dataset_two_contents = input_file.read()

    line = (f'dataset_one_contents: {dataset_one_contents} || '
            f'dataset_two_contents: {dataset_two_contents} || '
            f'message: {message} || '
            f'input_bool: {input_bool}, type {type(input_bool)} || '
            f'input_dict: {input_dict}, type {type(input_dict)} || '
            f'input_list: {input_list}, type {type(input_list)} \n')

    with open(model.path, 'w') as output_file:
        for i in range(num_steps):
            output_file.write('Step {}\n{}\n=====\n'.format(i, line))

    # model is an instance of Model artifact, which has a .metadata dictionary
    # to store arbitrary metadata for the output artifact.
    model.metadata['accuracy'] = 0.9


@dsl.pipeline(pipeline_root='', name='my-test-pipeline-beta')
def pipeline(message: str = 'message'):
    preprocess_task = preprocess(message=message)
    train_task = train(
        dataset_one=preprocess_task.outputs['output_dataset_one'],
        dataset_two=preprocess_task.outputs['output_dataset_two'],
        message=preprocess_task.outputs['output_parameter'],
        input_bool=preprocess_task.outputs['output_bool_parameter'],
        input_dict=preprocess_task.outputs['output_dict_parameter'],
        input_list=preprocess_task.outputs['output_list_parameter'],
    )


if __name__ == '__main__':
    compiler.Compiler().compile(
        pipeline_func=pipeline, package_path=__file__.replace('.py', '.yaml'))