/**
* Copyright 2013 Netflix, Inc.
* <p/>
* 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
* <p/>
* http://www.apache.org/licenses/LICENSE-2.0
* <p/>
* 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.servo.publish;
import com.netflix.servo.Metric;
import com.netflix.servo.tag.SortedTagList;
import com.netflix.servo.util.UnmodifiableList;
import org.testng.annotations.Test;
import java.util.List;
import static org.testng.Assert.assertEquals;
import static org.testng.Assert.assertTrue;
public class AsyncMetricObserverTest {
private List<Metric> mkList(int v) {
return UnmodifiableList.of(new Metric("m", SortedTagList.EMPTY, 0L, v));
}
@Test
public void testUpdate() throws Exception {
MemoryMetricObserver mmo = new MemoryMetricObserver("mem", 50);
AsyncMetricObserver amo = new AsyncMetricObserver("async", mmo, 50);
amo.update(mkList(1));
amo.update(mkList(2));
amo.update(mkList(3));
amo.update(mkList(4));
Thread.sleep(1000);
assertEquals(mmo.getObservations(),
UnmodifiableList.of(mkList(1), mkList(2), mkList(3), mkList(4)));
amo.stop();
}
@Test
public void testExceedQueueSize() throws Exception {
MemoryMetricObserver mmo = new MemoryMetricObserver("mem", 50);
MetricObserver smo = new SlowMetricObserver(mmo, 500L);
AsyncMetricObserver amo = new AsyncMetricObserver("async", smo, 2);
amo.update(mkList(1));
amo.update(mkList(2));
amo.update(mkList(3));
amo.update(mkList(4));
Thread.sleep(4000);
// We should always get at least queueSize updates
List<List<Metric>> observations = mmo.getObservations();
assertTrue(observations.size() >= 2);
// Older entries are overwritten, the last queueSize updates should
// be in the output
int last = observations.size() - 1;
assertEquals(observations.get(last - 1), mkList(3));
assertEquals(observations.get(last), mkList(4));
amo.stop();
}
@Test
public void testExpiration() throws Exception {
MemoryMetricObserver mmo = new MemoryMetricObserver("mem", 50);
MetricObserver smo = new SlowMetricObserver(mmo, 500L);
AsyncMetricObserver amo = new AsyncMetricObserver("async", smo, 50, 250);
amo.update(mkList(1));
amo.update(mkList(2));
amo.update(mkList(3));
amo.update(mkList(4));
Thread.sleep(4000);
// Only the first update should have made it on time
List<List<Metric>> observations = mmo.getObservations();
assertEquals(observations.size(), 1);
assertEquals(observations.get(0), mkList(1));
amo.stop();
}
@Test
public void testFailedUpdate() throws Exception {
// Just making sure exception does not propagate
MetricObserver fmo = new FailingMetricObserver();
AsyncMetricObserver amo = new AsyncMetricObserver("async", fmo, 50, 250);
amo.update(mkList(1));
amo.update(mkList(1));
amo.update(mkList(1));
amo.update(mkList(1));
amo.update(mkList(1));
amo.update(mkList(1));
Thread.sleep(1000);
amo.stop();
}
}