/**
 * 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.impl;

import org.apache.hadoop.metrics2.AbstractMetric;
import org.apache.hadoop.metrics2.MetricsRecord;
import org.apache.hadoop.metrics2.MetricsTag;
import org.apache.hadoop.metrics2.sink.GraphiteSink;
import org.junit.Test;
import org.mockito.ArgumentCaptor;
import org.mockito.internal.util.reflection.Whitebox;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.Collections;

import static org.junit.Assert.assertEquals;
import static org.mockito.Matchers.anyString;
import static org.mockito.Matchers.eq;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.reset;


public class TestGraphiteMetrics {
    private AbstractMetric makeMetric(String name, Number value) {
        AbstractMetric metric = mock(AbstractMetric.class);
        when(metric.name()).thenReturn(name);
        when(metric.value()).thenReturn(value);
        return metric;
    }

    private GraphiteSink.Graphite makeGraphite() {
      GraphiteSink.Graphite mockGraphite = mock(GraphiteSink.Graphite.class);
      when(mockGraphite.isConnected()).thenReturn(true);
      return mockGraphite;
    }

    @Test
    public void testPutMetrics() {
        GraphiteSink sink = new GraphiteSink();
        List<MetricsTag> tags = new ArrayList<MetricsTag>();
        tags.add(new MetricsTag(MsInfo.Context, "all"));
        tags.add(new MetricsTag(MsInfo.Hostname, "host"));
        Set<AbstractMetric> metrics = new HashSet<AbstractMetric>();
        metrics.add(makeMetric("foo1", 1.25));
        metrics.add(makeMetric("foo2", 2.25));
        MetricsRecord record = new MetricsRecordImpl(MsInfo.Context, (long) 10000, tags, metrics);

        ArgumentCaptor<String> argument = ArgumentCaptor.forClass(String.class);
        final GraphiteSink.Graphite mockGraphite = makeGraphite();
        Whitebox.setInternalState(sink, "graphite", mockGraphite);
        sink.putMetrics(record);

        try {
          verify(mockGraphite).write(argument.capture());
        } catch (IOException e) {
          e.printStackTrace();
        }

        String result = argument.getValue();

        assertEquals(true,
            result.equals("null.all.Context.Context=all.Hostname=host.foo1 1.25 10\n" +
            "null.all.Context.Context=all.Hostname=host.foo2 2.25 10\n") ||
            result.equals("null.all.Context.Context=all.Hostname=host.foo2 2.25 10\n" + 
            "null.all.Context.Context=all.Hostname=host.foo1 1.25 10\n"));
    }

    @Test
    public void testPutMetrics2() {
        GraphiteSink sink = new GraphiteSink();
        List<MetricsTag> tags = new ArrayList<MetricsTag>();
        tags.add(new MetricsTag(MsInfo.Context, "all"));
      tags.add(new MetricsTag(MsInfo.Hostname, null));
        Set<AbstractMetric> metrics = new HashSet<AbstractMetric>();
        metrics.add(makeMetric("foo1", 1));
        metrics.add(makeMetric("foo2", 2));
        MetricsRecord record = new MetricsRecordImpl(MsInfo.Context, (long) 10000, tags, metrics);


        ArgumentCaptor<String> argument = ArgumentCaptor.forClass(String.class);
        final GraphiteSink.Graphite mockGraphite = makeGraphite();
        Whitebox.setInternalState(sink, "graphite", mockGraphite);
        sink.putMetrics(record);

        try {
            verify(mockGraphite).write(argument.capture());
        } catch (IOException e) {
            e.printStackTrace();
        }

        String result = argument.getValue();

        assertEquals(true,
            result.equals("null.all.Context.Context=all.foo1 1 10\n" + 
            "null.all.Context.Context=all.foo2 2 10\n") ||
            result.equals("null.all.Context.Context=all.foo2 2 10\n" + 
            "null.all.Context.Context=all.foo1 1 10\n"));
    }

    /**
     * Assert that timestamps are converted correctly, ticket HADOOP-11182
     */
    @Test
    public void testPutMetrics3() {

      // setup GraphiteSink
      GraphiteSink sink = new GraphiteSink();
      final GraphiteSink.Graphite mockGraphite = makeGraphite();
      Whitebox.setInternalState(sink, "graphite", mockGraphite);

      // given two metrics records with timestamps 1000 milliseconds apart.
      List<MetricsTag> tags = Collections.emptyList();
      Set<AbstractMetric> metrics = new HashSet<AbstractMetric>();
      metrics.add(makeMetric("foo1", 1));
      MetricsRecord record1 = new MetricsRecordImpl(MsInfo.Context, 1000000000000L, tags, metrics);
      MetricsRecord record2 = new MetricsRecordImpl(MsInfo.Context, 1000000001000L, tags, metrics);

      sink.putMetrics(record1);
      sink.putMetrics(record2);

      sink.flush();
      try {
        sink.close();
      } catch(IOException e) {
        e.printStackTrace();
      }

      // then the timestamps in the graphite stream should differ by one second.
      try {
        verify(mockGraphite).write(eq("null.default.Context.foo1 1 1000000000\n"));
        verify(mockGraphite).write(eq("null.default.Context.foo1 1 1000000001\n"));
      } catch (IOException e) {
        e.printStackTrace();
      }
    }

    @Test
    public void testFailureAndPutMetrics() throws IOException {
      GraphiteSink sink = new GraphiteSink();
      List<MetricsTag> tags = new ArrayList<MetricsTag>();
      tags.add(new MetricsTag(MsInfo.Context, "all"));
      tags.add(new MetricsTag(MsInfo.Hostname, "host"));
      Set<AbstractMetric> metrics = new HashSet<AbstractMetric>();
      metrics.add(makeMetric("foo1", 1.25));
      metrics.add(makeMetric("foo2", 2.25));
      MetricsRecord record = new MetricsRecordImpl(MsInfo.Context, (long) 10000, tags, metrics);

      final GraphiteSink.Graphite mockGraphite = makeGraphite();
      Whitebox.setInternalState(sink, "graphite", mockGraphite);

      // throw exception when first try
      doThrow(new IOException("IO exception")).when(mockGraphite).write(anyString());

      sink.putMetrics(record);
      verify(mockGraphite).write(anyString());
      verify(mockGraphite).close();

      // reset mock and try again
      reset(mockGraphite);
      when(mockGraphite.isConnected()).thenReturn(false);

      ArgumentCaptor<String> argument = ArgumentCaptor.forClass(String.class);
      sink.putMetrics(record);

      verify(mockGraphite).write(argument.capture());
      String result = argument.getValue();

      assertEquals(true,
          result.equals("null.all.Context.Context=all.Hostname=host.foo1 1.25 10\n" +
          "null.all.Context.Context=all.Hostname=host.foo2 2.25 10\n") ||
          result.equals("null.all.Context.Context=all.Hostname=host.foo2 2.25 10\n" +
          "null.all.Context.Context=all.Hostname=host.foo1 1.25 10\n"));
    }

    @Test
    public void testClose(){
        GraphiteSink sink = new GraphiteSink();
        final GraphiteSink.Graphite mockGraphite = makeGraphite();
        Whitebox.setInternalState(sink, "graphite", mockGraphite);
        try {
            sink.close();
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }

        try {
            verify(mockGraphite).close();
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
    }
}
