rondagostino commented on a change in pull request #9032: URL: https://github.com/apache/kafka/pull/9032#discussion_r472947852
########## File path: clients/src/main/java/org/apache/kafka/clients/admin/DescribeUserScramCredentialsResult.java ########## @@ -0,0 +1,50 @@ +/* + * 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.clients.admin; + +import org.apache.kafka.common.KafkaFuture; +import org.apache.kafka.common.annotation.InterfaceStability; + +import java.util.Map; +import java.util.Objects; + +/** + * The result of the {@link Admin#describeUserScramCredentials()} call. + * + * The API of this class is evolving, see {@link Admin} for details. + */ +@InterfaceStability.Evolving +public class DescribeUserScramCredentialsResult { + private final KafkaFuture<Map<String, UserScramCredentialsDescription>> future; Review comment: Ok, I think I follow now. You are saying that we could potentially implement describe by invoking 1+N requests to Kafka: one to get the list of credentials (either the list of all of them if we are asking for them all, or the explicitly requested ones we wanted), and then another N requests to get the data for each one. This on the surface seems like an anti-pattern, but it is not unreasonable for the case where the data is expensive to get in the first place — maybe we are forced to make 1 or more round-trips for each anyway. So as a general, reusable pattern, yes, I believe it works. So when we invoke describe, whether it is describe-all or just an explicit few, we return a single future, and that future returns a list of instances (UserName in this case): either 1 instance for each user that has at least 1 credential for the describe-all case, or one instance per distinct user explicitly requested otherwise. Then each UserName instance has the accessor you mentioned, which in this case returns Future<UserScramCredentialDescription>. Do I have that right? ---------------------------------------------------------------- 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: us...@infra.apache.org
