KafkaRestApplication.java

/*
 * Copyright 2015 Confluent Inc.
 *
 * Licensed 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 io.confluent.kafkarest;

import org.apache.kafka.common.security.JaasUtils;

import java.util.Properties;

import javax.ws.rs.core.Configurable;

import io.confluent.kafkarest.exceptions.ZkExceptionMapper;
import io.confluent.kafkarest.resources.BrokersResource;
import io.confluent.kafkarest.resources.ConsumersResource;
import io.confluent.kafkarest.resources.PartitionsResource;
import io.confluent.kafkarest.resources.RootResource;
import io.confluent.kafkarest.resources.TopicsResource;
import io.confluent.kafkarest.v2.KafkaConsumerManager;
import io.confluent.rest.Application;
import io.confluent.rest.RestConfigException;
import kafka.utils.ZkUtils;

/**
 * Utilities for configuring and running an embedded Kafka server.
 */
public class KafkaRestApplication extends Application<KafkaRestConfig> {

  ZkUtils zkUtils;
  Context context;

  public KafkaRestApplication() throws RestConfigException {
    this(new Properties());
  }

  public KafkaRestApplication(Properties props) throws RestConfigException {
    super(new KafkaRestConfig(props));
  }

  public KafkaRestApplication(KafkaRestConfig config) {
    super(config);
  }

  @Override
  public void setupResources(Configurable<?> config, KafkaRestConfig appConfig) {
    setupInjectedResources(config, appConfig, null, null, null, null, null, null, null);
  }

  /**
   * Helper that does normal setup, but uses injected components so their configs or implementations
   * can be customized for testing. This only exists to support TestKafkaRestApplication
   */
  protected void setupInjectedResources(
      Configurable<?> config, KafkaRestConfig appConfig,
      ZkUtils zkUtils, MetadataObserver mdObserver,
      ProducerPool producerPool,
      ConsumerManager consumerManager,
      SimpleConsumerFactory simpleConsumerFactory,
      SimpleConsumerManager simpleConsumerManager,
      KafkaConsumerManager kafkaConsumerManager
  ) {
    config.register(new ZkExceptionMapper(appConfig));

    if (zkUtils == null) {
      zkUtils = ZkUtils.apply(
          appConfig.getString(KafkaRestConfig.ZOOKEEPER_CONNECT_CONFIG),
          30000,
          30000,
          JaasUtils.isZkSecurityEnabled()
      );
    }
    if (mdObserver == null) {
      mdObserver = new MetadataObserver(appConfig, zkUtils);
    }
    if (producerPool == null) {
      producerPool = new ProducerPool(appConfig, zkUtils);
    }
    if (consumerManager == null) {
      consumerManager = new ConsumerManager(appConfig, mdObserver);
    }
    if (simpleConsumerFactory == null) {
      simpleConsumerFactory = new SimpleConsumerFactory(appConfig);
    }
    if (simpleConsumerManager == null) {
      simpleConsumerManager =
          new SimpleConsumerManager(appConfig, mdObserver, simpleConsumerFactory);
    }
    if (kafkaConsumerManager == null) {
      kafkaConsumerManager = new KafkaConsumerManager(appConfig);
    }

    this.zkUtils = zkUtils;
    context =
        new Context(
            appConfig,
            mdObserver,
            producerPool,
            consumerManager,
            simpleConsumerManager,
            kafkaConsumerManager
        );
    config.register(RootResource.class);
    config.register(new BrokersResource(context));
    config.register(new TopicsResource(context));
    config.register(new PartitionsResource(context));
    config.register(new ConsumersResource(context));
    config.register(new io.confluent.kafkarest.resources.v2.ConsumersResource(context));
    config.register(new io.confluent.kafkarest.resources.v2.PartitionsResource(context));
  }

  @Override
  public void onShutdown() {
    context.getConsumerManager().shutdown();
    context.getProducerPool().shutdown();
    context.getSimpleConsumerManager().shutdown();
    context.getMetadataObserver().shutdown();
    zkUtils.close();
  }
}