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_r407687053
########## File path: pinot-spi/src/main/java/org/apache/pinot/spi/data/function/evaluators/ExpressionEvaluator.java ########## @@ -0,0 +1,43 @@ +/** + * 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 java.util.List; +import org.apache.pinot.spi.data.readers.GenericRow; + + +/** + * Interface for evaluators of transform function expressions of schema field specs + * They transformFunction follows the convention: + * "transformFunction": "FunctionType({function}, argument1, argument2,...argumentN)" + * For example, + * "transformFunction" : "Groovy({firstName + ' ' + lastName}, firstName, lastName)" + */ +public interface ExpressionEvaluator { + + /** + * Get the arguments of the function + */ + List<String> getArguments(); + + /** + * Evaluate the function on the generic row and return the result + */ + Object evaluate(GenericRow genericRow); Review comment: We should standardize what data types are allowed in the GenericRow so that RecordReader and RecordExtractor can always extract the row into the supported data types, and ExpressionEvaluator can only evaluate values into these types ---------------------------------------------------------------- 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]
