pipelines/sdk/python/kfp/v2/components/experimental/base_component.py

99 lines
3.5 KiB
Python

# 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.
"""Base class for KFP components."""
import abc
from kfp.v2.components.experimental import component_spec as cspec
from kfp.v2.components.experimental import pipeline_task
class BaseComponent(metaclass=abc.ABCMeta):
"""Base class for a component.
Attributes:
name: The name of the component.
component_spec: The component definition.
"""
def __init__(self, component_spec: cspec.ComponentSpec):
"""Init function for BaseComponent.
Args:
component_spec: The component definition.
"""
self.component_spec = component_spec
self.name = component_spec.name
self._component_inputs = set(self.component_spec.inputs.keys())
def __call__(self, *args, **kwargs) -> pipeline_task.PipelineTask:
"""Creates a PipelineTask object.
The arguments are generated on the fly based on component input
definitions.
"""
task_inputs = {}
if len(args) > 0:
raise TypeError(
'Components must be instantiated using keyword arguments. Positional '
f'parameters are not allowed (found {len(args)} such parameters for '
f'component "{self.name}").')
for k, v in kwargs.items():
if k not in self._component_inputs:
raise TypeError(
f'{self.name}() got an unexpected keyword argument "{k}".')
if k in task_inputs:
raise TypeError(
f'{self.name}() got multiple values for argument "{k}".')
task_inputs[k] = v
# Fill in default value if there was no user provided value
for name, input_spec in self.component_spec.inputs.items():
if input_spec.default is not None and name not in task_inputs:
task_inputs[name] = input_spec.default
missing_arguments = [
name for name in self.component_spec.inputs
if name not in task_inputs
]
if missing_arguments:
argument_or_arguments = 'argument' if len(
missing_arguments) == 1 else 'arguments'
arguments = ','.join(missing_arguments)
raise TypeError(
f'{self.name}() missing {len(missing_arguments)} required positional '
f'{argument_or_arguments}: {arguments}.')
return pipeline_task.create_pipeline_task(
component_spec=self.component_spec,
arguments=task_inputs,
)
@abc.abstractmethod
def execute(self, *args, **kwargs):
"""Executes the component given the required inputs.
Subclasses of BaseComponent must override this abstract method
in order to be instantiated. For Python function-based
component, the implementation of this method could be calling
the function. For "Bring your own container" component, the
implementation of this method could be `docker run`.
"""
pass