AtlasTimerTest.java

/*
 * Copyright 2014-2016 Netflix, 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 com.netflix.spectator.atlas;

import com.netflix.spectator.api.DefaultRegistry;
import com.netflix.spectator.api.Id;
import com.netflix.spectator.api.ManualClock;
import com.netflix.spectator.api.Measurement;
import com.netflix.spectator.api.Registry;
import com.netflix.spectator.api.Utils;
import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

import java.util.concurrent.TimeUnit;


@RunWith(JUnit4.class)
public class AtlasTimerTest {

  private ManualClock clock = new ManualClock();
  private Registry registry = new DefaultRegistry();
  private long step = 10000L;
  private AtlasTimer dist = new AtlasTimer(registry.createId("test"), clock, step);

  private void checkValue(long count, long amount, double square, long max) {
    int num = 0;
    for (Measurement m : dist.measure()) {
      String stat = Utils.getTagValue(m.id(), "statistic");
      DsType ds = "max".equals(stat) ? DsType.gauge : DsType.rate;
      Id expectedId = dist.id().withTag(ds).withTag("statistic", stat);
      Assert.assertEquals(expectedId, m.id());
      switch (stat) {
        case "count":
          Assert.assertEquals(count / 10.0, m.value(), 1e-12);
          break;
        case "totalTime":
          Assert.assertEquals(amount / 10.0e9, m.value(), 1e-12);
          break;
        case "totalOfSquares":
          Assert.assertEquals(square / 10.0e18, m.value(), 1e-12);
          break;
        case "max":
          Assert.assertEquals(max / 1e9, m.value(), 1e-12);
          break;
        default:
          throw new IllegalArgumentException("unknown stat: " + stat);
      }
      Assert.assertEquals(count, dist.count());
      Assert.assertEquals(amount, dist.totalTime());
      ++num;
    }
    Assert.assertEquals(4, num);
  }

  @Test
  public void measuredIdHasDsType() {
    checkValue(0, 0, 0, 0);
  }

  @Test
  public void recordOne() {
    dist.record(1, TimeUnit.NANOSECONDS);
    checkValue(0, 0, 0, 0);

    clock.setWallTime(step + 1);
    checkValue(1, 1, 1, 1);
  }

  @Test
  public void recordTwo() {
    dist.record(2, TimeUnit.NANOSECONDS);
    checkValue(0, 0, 0, 0);

    clock.setWallTime(step + 1);
    checkValue(1, 2, 4, 2);
  }

  @Test
  public void recordMillis() {
    dist.record(2, TimeUnit.MILLISECONDS);
    clock.setWallTime(step + 1);
    checkValue(1, 2000000L, 4000000000000L, 2000000L);
  }

  @Test
  public void recordSquaresOverflow() {
    long v = (long) (Math.sqrt(Long.MAX_VALUE) / 1e9) + 1;
    dist.record(v, TimeUnit.SECONDS);
    clock.setWallTime(step + 1);
    double square = 1e18 * v * v;
    checkValue(1, v * 1000000000L, square, v * 1000000000L);
  }

  @Test
  public void recordZero() {
    dist.record(0, TimeUnit.NANOSECONDS);
    clock.setWallTime(step + 1);
    checkValue(1, 0, 0, 0);
  }

  @Test
  public void recordNegativeValue() {
    dist.record(-2, TimeUnit.NANOSECONDS);
    clock.setWallTime(step + 1);
    checkValue(1, 0, 0, 0);
  }

  @Test
  public void recordSeveralValues() {
    dist.record(1, TimeUnit.NANOSECONDS);
    dist.record(2, TimeUnit.NANOSECONDS);
    dist.record(3, TimeUnit.NANOSECONDS);
    dist.record(1, TimeUnit.NANOSECONDS);
    clock.setWallTime(step + 1);
    checkValue(4, 1 + 2 + 3 + 1, 1 + 4 + 9 + 1, 3);
  }

  @Test
  public void recordRunnable() {
    dist.record(() -> clock.setMonotonicTime(clock.monotonicTime() + 2));
    clock.setWallTime(step + 1);
    checkValue(1, 2, 4, 2);
  }

  @Test
  public void recordCallable() throws Exception {
    String s = dist.record(() -> {
      clock.setMonotonicTime(clock.monotonicTime() + 2);
      return "foo";
    });
    Assert.assertEquals("foo", s);
    clock.setWallTime(step + 1);
    checkValue(1, 2, 4, 2);
  }

  @Test
  public void rollForward() {
    dist.record(42, TimeUnit.NANOSECONDS);
    clock.setWallTime(step + 1);
    checkValue(1, 42, 42 * 42, 42);
    clock.setWallTime(step + step + 1);
    checkValue(0, 0, 0, 0);
  }
}