mimaison commented on code in PR #17511: URL: https://github.com/apache/kafka/pull/17511#discussion_r1850123974
########## clients/src/main/java/org/apache/kafka/common/internals/Plugin.java: ########## @@ -0,0 +1,78 @@ +/* + * 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.common.internals; + +import org.apache.kafka.common.metrics.Metrics; +import org.apache.kafka.common.metrics.Monitorable; +import org.apache.kafka.common.metrics.internals.PluginMetricsImpl; + +import java.util.ArrayList; +import java.util.LinkedHashMap; +import java.util.List; +import java.util.Map; +import java.util.Optional; +import java.util.function.Supplier; + +public class Plugin<T> implements Supplier<T>, AutoCloseable { + + private final T instance; + private final Optional<PluginMetricsImpl> pluginMetrics; + + private Plugin(T instance, PluginMetricsImpl pluginMetrics) { + this.instance = instance; + this.pluginMetrics = Optional.ofNullable(pluginMetrics); + } + + public static <T> Plugin<T> wrapInstance(T instance, Metrics metrics, String key) { + return wrapInstance(instance, metrics, () -> tags(key, instance)); + } + + private static <T> Map<String, String> tags(String key, T instance) { + Map<String, String> tags = new LinkedHashMap<>(); + tags.put("config", key); + tags.put("class", instance.getClass().getSimpleName()); + return tags; + } + + public static <T> List<Plugin<T>> wrapInstances(List<T> instances, Metrics metrics, String key) { + List<Plugin<T>> plugins = new ArrayList<>(); + for (T instance : instances) { + plugins.add(wrapInstance(instance, metrics, key)); + } + return plugins; + } + + public static <T> Plugin<T> wrapInstance(T instance, Metrics metrics, Supplier<Map<String, String>> tagsSupplier) { + PluginMetricsImpl pluginMetrics = null; + if (instance instanceof Monitorable && metrics != null) { + pluginMetrics = new PluginMetricsImpl(metrics, tagsSupplier.get()); + ((Monitorable) instance).withPluginMetrics(pluginMetrics); + } + return new Plugin<>(instance, pluginMetrics); + } + + @Override + public T get() { + return instance; + } + + @Override + public void close() throws Exception { Review Comment: That's a good point! And thanks for taking the time to consider the alternatives and suggest solutions. I agree that the plugin instance should be closed first. This allows the plugin `close()` method to update metrics. Also when closing the PluginMetrics instance afterwards, this allows to "lock" it as in theory it should not receive further calls. I've opted to use `Utils.closeQuietly()` so we can capture if any of the plugin or PluginMetrics instance fail closing. -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
