content: /*
   * 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.connect.runtime;
  
  import org.apache.kafka.common.config.ConfigDef;
  import org.apache.kafka.common.config.ConfigTransformer;
  import org.apache.kafka.common.config.ConfigTransformerResult;
  import org.apache.kafka.common.config.provider.ConfigProvider;
  import org.apache.kafka.common.utils.Utils;
  import org.apache.kafka.connect.runtime.Herder.ConfigReloadAction;
  import org.apache.kafka.connect.util.Callback;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.Locale;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.ConcurrentMap;
  
  /**
   * A wrapper class to perform configuration transformations and schedule reloads for any
   * retrieved TTL values.
   */
  public class WorkerConfigTransformer implements AutoCloseable {
      private static final Logger log = LoggerFactory.getLogger(WorkerConfigTransformer.class);
  
      private final Worker worker;
      private final ConfigTransformer configTransformer;
      private final ConcurrentMap<String, Map<String, HerderRequest>> requests = new ConcurrentHashMap<>();
      private final Map<String, ConfigProvider> configProviders;
  
      public WorkerConfigTransformer(Worker worker, Map<String, ConfigProvider> configProviders) {
          this.worker = worker;
          this.configProviders = configProviders;
          this.configTransformer = new ConfigTransformer(configProviders);
      }
  
      public Map<String, String> transform(Map<String, String> configs) {
          return transform(null, configs);
      }
  
      public Map<String, String> transform(String connectorName, Map<String, String> configs) {
          if (configs == null) return null;
          ConfigTransformerResult result = configTransformer.transform(configs);
          if (connectorName != null) {
              String key = ConnectorConfig.CONFIG_RELOAD_ACTION_CONFIG;
              String action = (String) ConfigDef.parseType(key, configs.get(key), ConfigDef.Type.STRING);
              if (action == null) {
                  // The default action is "restart".
                  action = ConnectorConfig.CONFIG_RELOAD_ACTION_RESTART;
              }
              ConfigReloadAction reloadAction = ConfigReloadAction.valueOf(action.toUpperCase(Locale.ROOT));
              if (reloadAction == ConfigReloadAction.RESTART) {
                  scheduleReload(connectorName, result.ttls());
              }
          }
          return result.data();
      }
  
      private void scheduleReload(String connectorName, Map<String, Long> ttls) {
          for (Map.Entry<String, Long> entry : ttls.entrySet()) {
              scheduleReload(connectorName, entry.getKey(), entry.getValue());
          }
      }
  
      private void scheduleReload(String connectorName, String path, long ttl) {
          Map<String, HerderRequest> connectorRequests = requests.computeIfAbsent(connectorName, s -> new ConcurrentHashMap<>());
          connectorRequests.compute(path, (s, previousRequest) -> {
              if (previousRequest != null) {
                  // Delete previous request for ttl which is now stale
                  previousRequest.cancel();
              }
              log.info("Scheduling a restart of connector {} in {} ms", connectorName, ttl);
              Callback<Void> cb = (error, result) -> {
                  if (error != null) {
                      log.error("Unexpected error during connector restart: ", error);
                  }
              };
              return worker.herder().restartConnector(ttl, connectorName, cb);
          });
      }
  
      @Override
      public void close() {
          configProviders.values().forEach(x -> Utils.closeQuietly(x, "config provider"));
      }
  }
  