zhipeng93 commented on code in PR #216: URL: https://github.com/apache/flink-ml/pull/216#discussion_r1169987013
########## flink-ml-tests/src/test/java/org/apache/flink/test/iteration/BoundedTailOperatorWithUnionInputIterationITCase.java: ########## @@ -0,0 +1,75 @@ +/* + * 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.test.iteration; + +import org.apache.flink.iteration.DataStreamList; +import org.apache.flink.iteration.IterationBody; +import org.apache.flink.iteration.IterationBodyResult; +import org.apache.flink.iteration.IterationConfig; +import org.apache.flink.iteration.IterationConfig.OperatorLifeCycle; +import org.apache.flink.iteration.Iterations; +import org.apache.flink.iteration.ReplayableDataStreamList; +import org.apache.flink.ml.common.iteration.TerminateOnMaxIter; +import org.apache.flink.streaming.api.datastream.DataStream; +import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment; + +import org.junit.Test; + +import static org.junit.Assert.assertEquals; + +/** Tests the case that Tail operator contains multiple inputs. */ +public class BoundedTailOperatorWithUnionInputIterationITCase { + + @Test + public void testTailOperatorWithUnionInput() { + StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment(); + DataStream<Long> input1 = env.fromSequence(0, 10); + DataStream<Long> input2 = env.fromSequence(0, 10); + String expectedErrorMessage = + "Tail operator should have only one input. Please check whether operator " + + "\"Union\" contains multiple inputs."; + + try { + Iterations.iterateBoundedStreamsUntilTermination( + DataStreamList.of(input1), + ReplayableDataStreamList.replay(input2), + new IterationConfig(OperatorLifeCycle.PER_ROUND), + new IterationBodyWithUnionAsFeedback()); + } catch (UnsupportedOperationException e) { + assertEquals(expectedErrorMessage, e.getMessage()); + } + } + + private static class IterationBodyWithUnionAsFeedback implements IterationBody { + + @Override + public IterationBodyResult process( + DataStreamList variableStreams, DataStreamList dataStreams) { + + DataStream<Long> variableStream = variableStreams.get(0); + DataStream<Long> constantStream = dataStreams.get(0); + DataStream<Integer> terminationCriteria = + constantStream.flatMap(new TerminateOnMaxIter<>(3)); + return new IterationBodyResult( + DataStreamList.of(variableStream.union(constantStream)), Review Comment: Currently `TailOperator` does not align the epoch watermarks from its inputs, thus will cause the result of iteration wrong. To support using `opA union opB` as the feedback, users can now use `(opA union opB).map(x -> x)` as a temp workaround. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
