pvary commented on code in PR #13032: URL: https://github.com/apache/iceberg/pull/13032#discussion_r2095584182
########## flink/v2.0/flink/src/main/java/org/apache/iceberg/flink/sink/dynamic/PartitionSpecEvolution.java: ########## @@ -0,0 +1,139 @@ +/* + * 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.iceberg.flink.sink.dynamic; + +import java.util.List; +import org.apache.iceberg.PartitionField; +import org.apache.iceberg.PartitionSpec; +import org.apache.iceberg.Schema; +import org.apache.iceberg.expressions.NamedReference; +import org.apache.iceberg.expressions.Term; +import org.apache.iceberg.expressions.UnboundTransform; +import org.apache.iceberg.relocated.com.google.common.collect.Iterables; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; + +/** Checks compatibility of PartitionSpecs and evolves one into the other. */ +public class PartitionSpecEvolution { + + private PartitionSpecEvolution() {} + + /** + * Checks whether two PartitionSpecs are compatible with each other. Less strict than {@code + * PartitionSpec#compatible} in the sense that it tolerates differently named partition fields, as + * long as their transforms and field names corresponding to their source ids match. + */ + public static boolean checkCompatibility(PartitionSpec spec1, PartitionSpec spec2) { + if (spec1.equals(spec2)) { + return true; + } + + if (spec1.fields().size() != spec2.fields().size()) { + return false; + } + + for (int i = 0; i < spec1.fields().size(); i++) { + PartitionField field1 = spec1.fields().get(i); + PartitionField field2 = spec2.fields().get(i); + if (!specFieldsAreCompatible(field1, spec1.schema(), field2, spec2.schema())) { + return false; + } + } + + return true; + } + + static PartitionSpecChanges evolve(PartitionSpec currentSpec, PartitionSpec targetSpec) { + if (currentSpec.compatibleWith(targetSpec)) { + return new PartitionSpecChanges(); + } + + PartitionSpecChanges result = new PartitionSpecChanges(); + + int maxNumFields = Math.max(currentSpec.fields().size(), targetSpec.fields().size()); + for (int i = 0; i < maxNumFields; i++) { + PartitionField currentField = Iterables.get(currentSpec.fields(), i, null); + PartitionField targetField = Iterables.get(targetSpec.fields(), i, null); + + if (!specFieldsAreCompatible( + currentField, currentSpec.schema(), targetField, targetSpec.schema())) { + + if (currentField != null) { + result.remove(toTerm(currentField, currentSpec.schema())); + } + + if (targetField != null) { + result.add(toTerm(targetField, targetSpec.schema())); + } + } + } + + return result; + } + + static class PartitionSpecChanges { + private final List<Term> termsToAdd = Lists.newArrayList(); + private final List<Term> termsToRemove = Lists.newArrayList(); + + public void add(Term term) { + termsToAdd.add(term); + } + + public void remove(Term term) { + termsToRemove.add(term); + } + + public List<Term> termsToAdd() { + return termsToAdd; + } + + public List<Term> termsToRemove() { + return termsToRemove; + } + + public boolean isEmpty() { + return termsToAdd.isEmpty() && termsToRemove.isEmpty(); + } + + @Override + public String toString() { + return "PartitionSpecChanges{" Review Comment: Maybe use `MoreObjects` -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
