/**
 * 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.hadoop.metrics2.sink.flume;

import static org.easymock.EasyMock.anyObject;
import static org.easymock.EasyMock.anyString;
import static org.easymock.EasyMock.createNiceMock;
import static org.easymock.EasyMock.eq;
import static org.easymock.EasyMock.expect;
import static org.powermock.api.easymock.PowerMock.mockStatic;
import static org.powermock.api.easymock.PowerMock.replay;
import static org.powermock.api.easymock.PowerMock.resetAll;
import static org.powermock.api.easymock.PowerMock.verifyAll;

import java.net.InetAddress;
import java.util.Collections;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import org.apache.flume.Context;
import org.apache.flume.instrumentation.util.JMXPollUtil;
import org.apache.hadoop.metrics2.sink.timeline.TimelineMetric;
import org.apache.hadoop.metrics2.sink.timeline.cache.TimelineMetricsCache;
import org.apache.hadoop.metrics2.sink.timeline.configuration.Configuration;
import org.easymock.EasyMock;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.api.easymock.PowerMock;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest({JMXPollUtil.class, Executors.class, FlumeTimelineMetricsSink.class})
public class FlumeTimelineMetricsSinkTest {
  @Test
  public void testNonNumericMetricMetricExclusion() throws InterruptedException {
    FlumeTimelineMetricsSink flumeTimelineMetricsSink = new FlumeTimelineMetricsSink();
    FlumeTimelineMetricsSink.TimelineMetricsCollector collector =
      flumeTimelineMetricsSink.new TimelineMetricsCollector();
    mockStatic(JMXPollUtil.class);
    EasyMock.expect(JMXPollUtil.getAllMBeans()).andReturn(
        Collections.singletonMap("component1", Collections.singletonMap("key1", "value1"))).once();
    replay(JMXPollUtil.class);
    collector.run();
    verifyAll();
  }

  @Test
  public void testNumericMetricSubmission() throws InterruptedException {
    FlumeTimelineMetricsSink flumeTimelineMetricsSink = new FlumeTimelineMetricsSink();
    FlumeTimelineMetricsSink.TimelineMetricsCollector collector =
      flumeTimelineMetricsSink.new TimelineMetricsCollector();
    mockStatic(JMXPollUtil.class);
    EasyMock.expect(JMXPollUtil.getAllMBeans()).andReturn(
        Collections.singletonMap("component1", Collections.singletonMap("key1", "42"))).once();
    replay(JMXPollUtil.class);
    collector.run();
    verifyAll();
  }

  private TimelineMetricsCache getTimelineMetricsCache(FlumeTimelineMetricsSink flumeTimelineMetricsSink) {
    TimelineMetricsCache timelineMetricsCache = EasyMock.createNiceMock(TimelineMetricsCache.class);
    flumeTimelineMetricsSink.setMetricsCaches(Collections.singletonMap("SINK",timelineMetricsCache));
    EasyMock.expect(timelineMetricsCache.getTimelineMetric("key1"))
        .andReturn(new TimelineMetric()).once();
    timelineMetricsCache.putTimelineMetric(anyObject(TimelineMetric.class));
    EasyMock.expectLastCall().once();
    return timelineMetricsCache;
  }

  @Test
  public void testMonitorRestart() throws InterruptedException {
    FlumeTimelineMetricsSink flumeTimelineMetricsSink = new FlumeTimelineMetricsSink();
    TimelineMetricsCache timelineMetricsCache = getTimelineMetricsCache(flumeTimelineMetricsSink);
    flumeTimelineMetricsSink.setPollFrequency(1);
    mockStatic(Executors.class);
    ScheduledExecutorService executor = createNiceMock(ScheduledExecutorService.class);
    expect(Executors.newSingleThreadScheduledExecutor()).andReturn(executor);
    FlumeTimelineMetricsSink.TimelineMetricsCollector collector = anyObject();
    TimeUnit unit = anyObject();
    expect(executor.scheduleWithFixedDelay(collector, eq(0), eq(1), unit)).andReturn(null);
    executor.shutdown();
    replay(timelineMetricsCache, Executors.class, executor);

    flumeTimelineMetricsSink.start();
    flumeTimelineMetricsSink.stop();

    verifyAll();
  }

  @Test
  public void testMetricsRetrievalExceptionTolerance() throws InterruptedException {
    FlumeTimelineMetricsSink flumeTimelineMetricsSink = new FlumeTimelineMetricsSink();
    FlumeTimelineMetricsSink.TimelineMetricsCollector collector =
      flumeTimelineMetricsSink.new TimelineMetricsCollector();
    mockStatic(JMXPollUtil.class);
    EasyMock.expect(JMXPollUtil.getAllMBeans()).
        andThrow(new RuntimeException("Failed to retrieve Flume Properties")).once();
    replay(JMXPollUtil.class);
    collector.run();
    verifyAll();
  }

  @Test
  @PrepareForTest({Configuration.class, FlumeTimelineMetricsSink.class})
  public void testGettingFqdn() throws Exception {
    FlumeTimelineMetricsSink flumeTimelineMetricsSink = new FlumeTimelineMetricsSink();
    Configuration config = createNiceMock(Configuration.class);

    expect(config.getProperty(anyString(), anyString()))
      .andReturn("60")
      .anyTimes();
    expect(config.getProperty(anyString()))
      .andReturn("60")
      .anyTimes();
    replay(config);

    PowerMock.expectNew(Configuration.class, anyString())
      .andReturn(config);
    replay(Configuration.class);

    // getHostName() returned FQDN
    InetAddress address = createNiceMock(InetAddress.class);
    expect(address.getHostName()).andReturn("hostname.domain").once();
    replay(address);

    mockStatic(InetAddress.class);
    expect(InetAddress.getLocalHost()).andReturn(address).once();
    replay(InetAddress.class);

    flumeTimelineMetricsSink.configure(new Context());
    verifyAll();

    resetAll();

    PowerMock.expectNew(Configuration.class, anyString())
      .andReturn(config);
    replay(Configuration.class);

    // getHostName() returned short hostname, getCanonicalHostName() called
    address = createNiceMock(InetAddress.class);
    expect(address.getHostName()).andReturn("hostname").once();
    expect(address.getCanonicalHostName()).andReturn("hostname.domain").once();
    replay(address);

    mockStatic(InetAddress.class);
    expect(InetAddress.getLocalHost()).andReturn(address).times(2);
    replay(InetAddress.class);

    flumeTimelineMetricsSink.configure(new Context());
    verifyAll();

  }

}