walterddr commented on a change in pull request #11344: [FLINK-16250][python][ml] Add interfaces for PipelineStage and Pipeline URL: https://github.com/apache/flink/pull/11344#discussion_r390727653
########## File path: flink-python/pyflink/ml/api/base.py ########## @@ -0,0 +1,275 @@ +################################################################################ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you 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. +################################################################################ + +import re + +from abc import ABCMeta, abstractmethod + +from pyflink.table.table_environment import TableEnvironment +from pyflink.table.table import Table +from pyflink.ml.api.param import WithParams, Params +from py4j.java_gateway import get_field + + +class PipelineStage(WithParams): + """ + Base class for a stage in a pipeline. The interface is only a concept, and does not have any + actual functionality. Its subclasses must be either Estimator or Transformer. No other classes + should inherit this interface directly. + + Each pipeline stage is with parameters, and requires a public empty constructor for + restoration in Pipeline. + """ + + def __init__(self, params=None): + if params is None: + self._params = Params() + else: + self._params = params + + def get_params(self) -> Params: + return self._params + + def _convert_params_to_java(self, j_pipeline_stage): + for param in self._params._param_map: + java_param = self._make_java_param(j_pipeline_stage, param) + java_value = self._make_java_value(self._params._param_map[param]) + j_pipeline_stage.set(java_param, java_value) + + @staticmethod + def _make_java_param(j_pipeline_stage, param): + # camel case to snake case + name = re.sub(r'(?<!^)(?=[A-Z])', '_', param.name).upper() + return get_field(j_pipeline_stage, name) + + @staticmethod + def _make_java_value(obj): + """ Convert Python object into Java """ + if isinstance(obj, list): + obj = [PipelineStage._make_java_value(x) for x in obj] + return obj Review comment: These 2 utils are extremely useful, not just to PipelineStage IMO. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
