viirya commented on a change in pull request #31476: URL: https://github.com/apache/spark/pull/31476#discussion_r575701986
########## File path: sql/catalyst/src/main/java/org/apache/spark/sql/connector/CustomMetric.java ########## @@ -0,0 +1,61 @@ +/* + * 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.spark.sql.connector; + +import org.apache.spark.annotation.Evolving; +import org.apache.spark.sql.connector.read.PartitionReader; +import org.apache.spark.sql.connector.read.Scan; + +/** + * A custom metric. This is a logical representation of a metric reported by data sources during + * read path. Data sources can report supported metric list by {@link Scan} to Spark in query + * planning. During query execution, Spark will collect the metrics per partition by + * {@link PartitionReader} and combine metrics from partitions to the final result. How Spark + * combines metrics depends on the metric type. For streaming query, Spark will collect and combine + * metrics for a final result per micro batch. + * + * The metrics will be gathered during query execution back to the driver and then combined. The + * final result will be shown up in the physical operator in Spark UI. + * + * @since 3.2.0 + */ +@Evolving +public interface CustomMetric { + /** + * Returns the name of custom metric. + */ + String name(); + + /** + * Returns the description of custom metric. + */ + String description(); + + /** + * Supported metric type. The metric types must be supported by Spark SQL internal metrics. + * SUM: Spark sums up metrics from partitions as the final result. + */ + enum MetricType { + SUM Review comment: I only use sum metric for now for the Kafka scan purpose. So I leave other possible metric type (size, timing, average) out for now to make it simpler at the beginning. ---------------------------------------------------------------- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
