mjsax commented on code in PR #23092: URL: https://github.com/apache/kafka/pull/23092#discussion_r3761097508
########## group-coordinator/src/main/java/org/apache/kafka/coordinator/group/streams/assignor/AssignmentConfigsImpl.java: ########## @@ -0,0 +1,88 @@ +/* + * 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.kafka.coordinator.group.streams.assignor; + +import org.apache.kafka.coordinator.group.GroupCoordinatorConfig; +import org.apache.kafka.coordinator.group.api.streams.assignor.AssignmentConfigs; + +import java.util.List; +import java.util.Map; +import java.util.Objects; + +/** + * The assignment configurations for a streams group. + * + * @param numStandbyReplicas The number of standby replicas for each task. + * @param rackAwareAssignmentTags The client tags used to distribute standby tasks across racks. + */ +public record AssignmentConfigsImpl( + int numStandbyReplicas, + List<String> rackAwareAssignmentTags +) implements AssignmentConfigs { + + // The names under which the configurations are passed to the assignor and recorded for the group. + public static final String NUM_STANDBY_REPLICAS_CONFIG = "num.standby.replicas"; + public static final String RACK_AWARE_ASSIGNMENT_TAGS_CONFIG = "rack.aware.assignment.tags"; + + /** + * The configs of a group that has none of them set, holding the default value of every configuration. + */ + public static final AssignmentConfigsImpl DEFAULT = new AssignmentConfigsImpl( + GroupCoordinatorConfig.STREAMS_GROUP_NUM_STANDBY_REPLICAS_DEFAULT, + // The parsed form of STREAMS_GROUP_RACK_AWARE_ASSIGNMENT_TAGS_DEFAULT, which ConfigDef spells as "". + List.of() + ); + + public AssignmentConfigsImpl { + // The list is exposed to a custom assignor through the public AssignmentConfigs interface. + rackAwareAssignmentTags = List.copyOf(Objects.requireNonNull(rackAwareAssignmentTags)); + } + + /** + * Converts the raw assignment configs computed for the group into the typed configs passed to the assignor. + */ + public static AssignmentConfigsImpl fromMap(Map<String, String> configs) { + // The map is empty when it was replayed from a group metadata record written before the last assignment + // configs were persisted. + if (configs.isEmpty()) { + return DEFAULT; + } + // The rack-aware assignment tags are only set when any are configured, and are joined from values that + // ConfigDef has already validated to be non-empty and free of surrounding whitespace. + String rackAwareAssignmentTags = configs.get(RACK_AWARE_ASSIGNMENT_TAGS_CONFIG); + return new AssignmentConfigsImpl( + Integer.parseInt(configs.get(NUM_STANDBY_REPLICAS_CONFIG)), Review Comment: Ok. Seems we are scattered logic, making it hard to reason about this... No critical for 4.4 release, but wondering if we could do a follow up cleanup PR, streamlining this a little bit better to make it easier as a (human 🤣) reviewer to follow... Maybe we should "unify" the raw `Map<String, String>` and `AssignmentConfigsImpl` somehow, to have a single object we use and pass around, an avoid converting the one into the other multiple times along the way, at different places. -- 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]
