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.camel.component.kafka;
  
  import java.util.Map;
  import java.util.Properties;
  import java.util.concurrent.ExecutorService;
  
  import org.apache.camel.Category;
  import org.apache.camel.Consumer;
  import org.apache.camel.MultipleConsumersSupport;
  import org.apache.camel.Processor;
  import org.apache.camel.Producer;
  import org.apache.camel.component.kafka.consumer.KafkaManualCommit;
  import org.apache.camel.component.kafka.consumer.KafkaManualCommitFactory;
  import org.apache.camel.spi.ClassResolver;
  import org.apache.camel.spi.EndpointServiceLocation;
  import org.apache.camel.spi.UriEndpoint;
  import org.apache.camel.spi.UriParam;
  import org.apache.camel.support.DefaultEndpoint;
  import org.apache.camel.support.SynchronousDelegateProducer;
  import org.apache.camel.util.CastUtils;
  import org.apache.kafka.clients.consumer.ConsumerConfig;
  import org.apache.kafka.clients.producer.Partitioner;
  import org.apache.kafka.clients.producer.ProducerConfig;
  import org.apache.kafka.common.security.auth.AuthenticateCallbackHandler;
  import org.apache.kafka.common.serialization.Deserializer;
  import org.apache.kafka.common.serialization.Serializer;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Send and receive messages to/from an Apache Kafka broker.
   */
  @UriEndpoint(firstVersion = "2.13.0", scheme = "kafka", title = "Kafka", syntax = "kafka:topic",
               category = { Category.MESSAGING }, headersClass = KafkaConstants.class)
  public class KafkaEndpoint extends DefaultEndpoint implements MultipleConsumersSupport, EndpointServiceLocation {
  
      private static final Logger LOG = LoggerFactory.getLogger(KafkaEndpoint.class);
  
      private static final String CALLBACK_HANDLER_CLASS_CONFIG = "sasl.login.callback.handler.class";
  
      @UriParam
      private KafkaConfiguration configuration = new KafkaConfiguration();
      @UriParam(label = "advanced")
      private KafkaClientFactory kafkaClientFactory;
      @UriParam(label = "consumer,advanced")
      private KafkaManualCommitFactory kafkaManualCommitFactory;
  
      public KafkaEndpoint() {
      }
  
      public KafkaEndpoint(String endpointUri, KafkaComponent component) {
          super(endpointUri, component);
      }
  
      @Override
      public KafkaComponent getComponent() {
          return (KafkaComponent) super.getComponent();
      }
  
      @Override
      public String getServiceUrl() {
          return configuration.getBrokers();
      }
  
      @Override
      public String getServiceProtocol() {
          return "kafka";
      }
  
      @Override
      public Map<String, String> getServiceMetadata() {
          if (configuration.getClientId() != null) {
              return Map.of("clientId", configuration.getClientId());
          }
          return null;
      }
  
      public KafkaConfiguration getConfiguration() {
          return configuration;
      }
  
      public void setConfiguration(KafkaConfiguration configuration) {
          this.configuration = configuration;
      }
  
      public KafkaClientFactory getKafkaClientFactory() {
          return this.kafkaClientFactory;
      }
  
      /**
       * Factory to use for creating {@link org.apache.kafka.clients.consumer.KafkaConsumer} and
       * {@link org.apache.kafka.clients.producer.KafkaProducer} instances. This allows to configure a custom factory to
       * create instances with logic that extends the vanilla Kafka clients.
       */
      public void setKafkaClientFactory(KafkaClientFactory kafkaClientFactory) {
          this.kafkaClientFactory = kafkaClientFactory;
      }
  
      public KafkaManualCommitFactory getKafkaManualCommitFactory() {
          return kafkaManualCommitFactory;
      }
  
      /**
       * Factory to use for creating {@link KafkaManualCommit} instances. This allows to plugin a custom factory to create
       * custom {@link KafkaManualCommit} instances in case special logic is needed when doing manual commits that
       * deviates from the default implementation that comes out of the box.
       */
      public void setKafkaManualCommitFactory(KafkaManualCommitFactory kafkaManualCommitFactory) {
          this.kafkaManualCommitFactory = kafkaManualCommitFactory;
      }
  
      @Override
      protected void doBuild() throws Exception {
          super.doBuild();
  
          if (kafkaClientFactory == null) {
              kafkaClientFactory = getComponent().getKafkaClientFactory();
          }
          if (kafkaManualCommitFactory == null) {
              kafkaManualCommitFactory = getComponent().getKafkaManualCommitFactory();
          }
      }
  
      @Override
      public Consumer createConsumer(Processor processor) throws Exception {
          KafkaConsumer consumer = new KafkaConsumer(this, processor);
          configureConsumer(consumer);
          return consumer;
      }
  
      @Override
      public Producer createProducer() throws Exception {
          KafkaProducer producer = createProducer(this);
          if (getConfiguration().isSynchronous()) {
              return new SynchronousDelegateProducer(producer);
          } else {
              return producer;
          }
      }
  
      @Override
      public boolean isMultipleConsumersSupported() {
          return true;
      }
  
      <T> Class<T> loadClass(Object o, ClassResolver resolver, Class<T> type) {
          if (o == null || o instanceof Class) {
              return CastUtils.cast((Class<?>) o);
          }
          String name = o.toString();
          Class<T> c = resolver.resolveClass(name, type);
          if (c == null) {
              c = resolver.resolveClass(name, type, getClass().getClassLoader());
          }
          if (c == null) {
              c = resolver.resolveClass(name, type, org.apache.kafka.clients.producer.KafkaProducer.class.getClassLoader());
          }
          return c;
      }
  
      void replaceWithClass(Properties props, String key, ClassResolver resolver, Class<?> type) {
          Class<?> c = loadClass(props.get(key), resolver, type);
          if (c != null) {
              props.put(key, c);
          }
      }
  
      public void updateClassProperties(Properties props) {
          try {
              if (getCamelContext() != null) {
                  ClassResolver resolver = getCamelContext().getClassResolver();
                  replaceWithClass(props, ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, resolver, Serializer.class);
                  replaceWithClass(props, ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, resolver, Serializer.class);
                  replaceWithClass(props, ProducerConfig.PARTITIONER_CLASS_CONFIG, resolver, Partitioner.class);
                  replaceWithClass(props, ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, resolver, Deserializer.class);
                  replaceWithClass(props, ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, resolver, Deserializer.class);
  
                  // because he property is not available in Kafka client, use a static string
                  replaceWithClass(props, CALLBACK_HANDLER_CLASS_CONFIG, resolver, AuthenticateCallbackHandler.class);
              }
          } catch (Exception t) {
              // can ignore and Kafka itself might be able to handle it, if not,
              // it will throw an exception
              LOG.debug("Problem loading classes for Serializers", t);
          }
      }
  
      public ExecutorService createExecutor(Object source) {
          return getCamelContext().getExecutorServiceManager().newFixedThreadPool(source,
                  "KafkaConsumer[" + configuration.getTopic() + "]", configuration.getConsumersCount());
      }
  
      public ExecutorService createProducerExecutor(Object source) {
          int core = getConfiguration().getWorkerPoolCoreSize();
          int max = getConfiguration().getWorkerPoolMaxSize();
          return getCamelContext().getExecutorServiceManager().newThreadPool(source,
                  "KafkaProducer[" + configuration.getTopic() + "]", core, max);
      }
  
      protected KafkaProducer createProducer(KafkaEndpoint endpoint) {
          return new KafkaProducer(endpoint);
      }
  
  }
  