walterddr commented on a change in pull request #8402: [FLINK-12473][ml] Add the interface of ML pipeline and ML lib URL: https://github.com/apache/flink/pull/8402#discussion_r286601213
########## File path: flink-ml/flink-ml-api/src/main/java/org/apache/flink/ml/api/core/PipelineStage.java ########## @@ -0,0 +1,70 @@ +/* + * 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. + */ + +package org.apache.flink.ml.api.core; + +import org.apache.flink.ml.api.misc.param.ParamInfo; +import org.apache.flink.ml.api.misc.param.WithParams; +import org.apache.flink.ml.api.misc.persist.Persistable; +import org.apache.flink.ml.util.param.ExtractParamInfosUtil; +import org.apache.flink.ml.util.persist.MLStageFactory; + +import com.google.gson.Gson; +import com.google.gson.JsonObject; + +import java.io.Serializable; +import java.util.HashMap; +import java.util.List; +import java.util.Map; + +/** + * 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. + * + * <p>Each pipeline stage is with parameters and meanwhile persistable. + * + * @param <T> The class type of the PipelineStage implementation itself, used by {@link + * org.apache.flink.ml.api.misc.param.WithParams} + * @see WithParams + */ +interface PipelineStage<T extends PipelineStage<T>> extends WithParams<T>, Serializable, + Persistable { + + default String toJson() { Review comment: +1 to expose more extendable interface in the next PR. I am still not fully convince that "toJson" addresses all of the concerns that we raise, especially once @blublinsky raised. but I also have a strong feeling that this can be address in future PR. One fundamental supporting factor I am on the "toJson" interface is that: a readable/editable format where a model can be bi-directionally converted in and out of FlinkML is 100% a need in multiple scenarios. for this PR purpose I don't think we need to focus on addressing "all" scenarios. what do you guys think? IMO the follow up can be on "export", "serving", or even "standardizing" the model ---------------------------------------------------------------- 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: [email protected] With regards, Apache Git Services
