Jackie-Jiang commented on a change in pull request #5238: Evaluate schema transform expressions during ingestion URL: https://github.com/apache/incubator-pinot/pull/5238#discussion_r407664797
########## File path: pinot-spi/src/main/java/org/apache/pinot/spi/data/function/evaluators/ExpressionEvaluatorFactory.java ########## @@ -0,0 +1,104 @@ +/** + * 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.pinot.spi.data.function.evaluators; + +import org.apache.pinot.spi.data.FieldSpec; +import org.apache.pinot.spi.data.TimeFieldSpec; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +/** + * Factory class to create an {@link ExpressionEvaluator} for the field spec based on the {@link FieldSpec#getTransformFunction()} + */ +public class ExpressionEvaluatorFactory { + + private static final Logger LOGGER = LoggerFactory.getLogger(ExpressionEvaluatorFactory.class); + + private ExpressionEvaluatorFactory() { + + } + + /** + * Creates the {@link ExpressionEvaluator} for the given field spec + * + * 1. If transform expression is defined, use it to create {@link ExpressionEvaluator} + * 2. For TIME column, {@link DefaultTimeSpecEvaluator} for backward compatible handling of time spec. This is needed until we migrate to {@link org.apache.pinot.spi.data.DateTimeFieldSpec} + * 3. For columns ending with __KEYS or __VALUES (used for interpreting Map column in Avro), create default functions for handing the Map + * 4. Return null, if none of the above + */ + public static ExpressionEvaluator getExpressionEvaluator(FieldSpec fieldSpec) { Review comment: Annotate as nullable for the return value ---------------------------------------------------------------- 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 --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
