org.eclipse.microprofile.metrics.Gauge Java Examples

/**
 * Given a Gauge with unit=dollars (custom unit),
 * check that the statistics from OpenMetricsExporter will be presented in dollars.
 */
@Test
public void gauge_customUnit_openMetrics() {
    MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.APPLICATION);
    Metadata metadata = Metadata.builder()
            .withName("gauge1")
            .withType(MetricType.GAUGE)
            .withUnit("dollars")
            .build();
    Gauge<Long> gaugeInstance = () -> 3L;
    registry.register(metadata, gaugeInstance);

    OpenMetricsExporter exporter = new OpenMetricsExporter();
    String exported = exporter.exportOneMetric(MetricRegistry.Type.APPLICATION, new MetricID("gauge1")).toString();

    Assert.assertThat(exported, containsString("application_gauge1_dollars 3.0"));
}
 

@Test
public void testGauges() {
    JsonExporter exporter = new JsonExporter();
    MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.APPLICATION);

    Gauge<Long> gaugeWithoutTags = () -> 1L;
    Gauge<Long> gaugeRed = () -> 2L;
    Gauge<Long> gaugeBlue = () -> 3L;

    final Metadata metadata = new MetadataBuilder()
            .withType(MetricType.GAUGE)
            .withName("mygauge")
            .build();

    registry.register(metadata, gaugeWithoutTags);
    registry.register(metadata, gaugeRed, new Tag("color", "red"));
    registry.register(metadata, gaugeBlue, new Tag("color", "blue"), new Tag("foo", "bar"));

    String result = exporter.exportMetricsByName(MetricRegistry.Type.APPLICATION, "mygauge").toString();
    System.out.println(result);
    JsonObject json = Json.createReader(new StringReader(result)).read().asJsonObject();

    assertEquals(1, json.getInt("mygauge"));
    assertEquals(2, json.getInt("mygauge;color=red"));
    assertEquals(3, json.getInt("mygauge;color=blue;foo=bar"));
}
 

@Test
@InSequence(1)
public void gaugeTagCalledWithDefaultValue() {

    @SuppressWarnings("unchecked")
    Gauge<Long> gaugeOne = (Gauge<Long>) registry.getGauge(gaugeOneMID);

    @SuppressWarnings("unchecked")
    Gauge<Long> gaugeTwo = (Gauge<Long>) registry.getGauge(gaugeTwoMID);

    assertThat("Gauge is not registered correctly", gaugeOne, notNullValue());
    assertThat("Gauge is not registered correctly", gaugeTwo, notNullValue());

    // Make sure that the gauge has the expected value
    assertThat("Gauge value is incorrect", gaugeOne.getValue(), is(equalTo(0L)));
    assertThat("Gauge value is incorrect", gaugeTwo.getValue(), is(equalTo(0L)));
}
 

@Test
@InSequence(2)
public void callGaugesAfterSetterCalls() {
    @SuppressWarnings("unchecked")
    Gauge<Long> parentGauge = (Gauge<Long>) registry.getGauge(parentMID);
    @SuppressWarnings("unchecked")
    Gauge<Long> childGauge = (Gauge<Long>) registry.getGauge(childMID);
    assertThat("Gauges are not registered correctly", parentGauge, notNullValue());
    assertThat("Gauges are not registered correctly", childGauge, notNullValue());

    // Call the setter methods and assert the gauges are up-to-date
    long parentValue = Math.round(Math.random() * Long.MAX_VALUE);
    pBean.setGauge(parentValue);
    long childValue = Math.round(Math.random() * Long.MAX_VALUE);
    bean.setChildGauge(childValue);
    assertThat("Gauge values are incorrect", Arrays.asList(parentGauge.getValue(), childGauge.getValue()), contains(parentValue, childValue));
}
 

@Test
@InSequence(2)
public void callGaugeTagAfterSetterCall() {
    @SuppressWarnings("unchecked")
    Gauge<Long> gaugeOne = (Gauge<Long>) registry.getGauge(gaugeOneMID);
    @SuppressWarnings("unchecked")
    Gauge<Long> gaugeTwo = (Gauge<Long>) registry.getGauge(gaugeTwoMID);
    assertThat("Gauge is not registered correctly", gaugeOne, notNullValue());
    assertThat("Gauge is not registered correctly", gaugeTwo, notNullValue());

    // Call the setter method and assert the gauge is up-to-date
    long value = Math.round(Math.random() * Long.MAX_VALUE);
    bean.setGaugeOne(value);
    
    long secondValue = Math.round(Math.random() * Long.MAX_VALUE);
    bean.setGaugeTwo(secondValue);
    
    assertThat("Gauge value is incorrect", gaugeOne.getValue(), is(equalTo(value)));
    assertThat("Gauge value is incorrect", gaugeTwo.getValue(), is(equalTo(secondValue)));
}
 

@Test
@InSequence(2)
public void callCachedMethodMultipleTimes() {
    assertThat("Metrics are not registered correctly", registry.getMetricIDs(),
        contains(cacheHitsMID, callsMID, hitsMID));
    Timer calls = registry.getTimer(callsMID);
    Meter hits = registry.getMeter(hitsMID);
    @SuppressWarnings("unchecked")
    Gauge<Double> gauge = (Gauge<Double>) registry.getGauge(cacheHitsMID);

    long count = 10 + Math.round(Math.random() * 10);
    for (int i = 0; i < count; i++) {
        bean.cachedMethod((Math.random() < 0.5));
    }

    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo((double) hits.getCount() / (double) calls.getCount())));
}
 

@Test
@InSequence(1)
public void countersNotIncrementedYet() {
    assertThat("Counters are not registered correctly", registry.getCounters(),
        allOf(
            hasKey(counter1MID),
            hasKey(counter2MID),
            not(hasKey(notRegMID))
        )
    );
    Counter counter1 = registry.getCounter(counter1MID);
    Counter counter2 = registry.getCounter(counter2MID);

    @SuppressWarnings("unchecked")
    Gauge<Double> gauge = (Gauge<Double>) registry.getGauge(ratioGaugeMID);
    assertThat("Gauge is not registered correctly", gauge, notNullValue());

    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo(((double) counter1.getCount()) / ((double) counter2.getCount()))));
}
 

private void runtimeMetrics(MetricRegistry registry) {
    RuntimeMXBean runtimeMXBean = ManagementFactory.getRuntimeMXBean();

    Metadata meta = Metadata.builder()
            .withName(JVM_UPTIME)
            .withType(MetricType.GAUGE)
            .withUnit(MetricUnits.MILLISECONDS)
            .withDisplayName("JVM Uptime")
            .withDescription("Displays the time from the start of the Java virtual machine in milliseconds.")
            .build();
    registry.register(meta, new Gauge() {
        @Override
        public Number getValue() {
            return runtimeMXBean.getUptime();
        }
    });
}
 

@Test
@InSequence(2)
public void incrementCountersFromRegistry() {
    assertThat("Counters are not registered correctly", registry.getCounters(),
        allOf(
            hasKey(counter1MID),
            hasKey(counter2MID),
            not(hasKey(notRegMID))
        )
    );
    Counter counter1 = registry.getCounter(counter1MID);
    Counter counter2 = registry.getCounter(counter2MID);

    @SuppressWarnings("unchecked")
    Gauge<Double> gauge = (Gauge<Double>) registry.getGauge(ratioGaugeMID);
    assertThat("Gauge is not registered correctly", gauge, notNullValue());

    counter1.inc(Math.round(Math.random() * Integer.MAX_VALUE));
    counter2.inc(Math.round(Math.random() * Integer.MAX_VALUE));

    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo(((double) counter1.getCount()) / ((double) counter2.getCount()))));
}
 

@Test
public void testMetricsOfDs1() throws SQLException {
    Counter acquireCount = registry.getCounters().get(new MetricID("agroal.acquire.count",
            new Tag("datasource", "ds1")));
    Gauge<?> maxUsed = registry.getGauges().get(new MetricID("agroal.max.used.count",
            new Tag("datasource", "ds1")));
    Assertions.assertNotNull(acquireCount, "Agroal metrics should be registered eagerly");
    Assertions.assertNotNull(maxUsed, "Agroal metrics should be registered eagerly");

    try (Connection connection = ds1.getConnection()) {
        try (Statement statement = connection.createStatement()) {
            statement.execute("SELECT 1");
        }
    }

    Assertions.assertEquals(1L, acquireCount.getCount());
    Assertions.assertEquals(1L, maxUsed.getValue());
}
 

@Test
public void testMetricsOfDefaultDS() throws SQLException {
    Counter acquireCount = registry.getCounters().get(new MetricID("agroal.acquire.count",
            new Tag("datasource", "default")));
    Gauge<?> maxUsed = registry.getGauges().get(new MetricID("agroal.max.used.count",
            new Tag("datasource", "default")));
    Assertions.assertNotNull(acquireCount, "Agroal metrics should be registered eagerly");
    Assertions.assertNotNull(maxUsed, "Agroal metrics should be registered eagerly");

    try (Connection connection = defaultDS.getConnection()) {
        try (Statement statement = connection.createStatement()) {
            statement.execute("SELECT 1");
        }
    }

    Assertions.assertEquals(1L, acquireCount.getCount());
    Assertions.assertEquals(1L, maxUsed.getValue());
}
 

@Test
public void testNameOverride() {
    OpenMetricsExporter exporter = new OpenMetricsExporter();
    MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.APPLICATION);

    Metadata metadata = new ExtendedMetadata("voltage1",
            "Voltage",
            "Measures your electric potential",
            MetricType.GAUGE,
            "volts",
            null,
            false,
            Optional.of(true),
            false,
            "baz");
    Tag tag = new Tag("a", "b");
    registry.register(metadata, (Gauge<Long>) () -> 3L, tag);

    String result = exporter.exportOneScope(MetricRegistry.Type.APPLICATION).toString();
    System.out.println(result);
    assertHasHelpLineExactlyOnce(result, "application_baz", "Measures your electric potential");
    assertHasTypeLineExactlyOnce(result, "application_baz", "gauge");
    assertHasValueLineExactlyOnce(result, "application_baz", "3.0", tag);
}
 

@Test
public void exportGauges() {
    OpenMetricsExporter exporter = new OpenMetricsExporter();
    MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.APPLICATION);

    Metadata metadata = Metadata
            .builder()
            .withType(MetricType.GAUGE)
            .withName("mygauge")
            .withDescription("awesome")
            .build();
    Tag blueTag = new Tag("color", "blue");
    registry.register(metadata, (Gauge<Long>) () -> 42L, blueTag);
    Tag greenTag = new Tag("color", "green");
    registry.register(metadata, (Gauge<Long>) () -> 26L, greenTag);

    String result = exporter.exportMetricsByName(MetricRegistry.Type.APPLICATION, "mygauge").toString();
    System.out.println(result);

    assertHasTypeLineExactlyOnce(result, "application_mygauge", "gauge");
    assertHasHelpLineExactlyOnce(result, "application_mygauge", "awesome");

    assertHasValueLineExactlyOnce(result, "application_mygauge", "42.0", blueTag);
    assertHasValueLineExactlyOnce(result, "application_mygauge", "26.0", greenTag);
}
 

@Test
public void testUptimeGaugeUnitConversion() {
    OpenMetricsExporter exporter = new OpenMetricsExporter();
    MetricRegistry baseRegistry = MetricRegistries.get(MetricRegistry.Type.BASE);

    Gauge gauge = new MGaugeImpl(JmxWorker.instance(), "java.lang:type=Runtime/Uptime");
    Metadata metadata = new ExtendedMetadata("jvm.uptime", "display name", "description", MetricType.GAUGE, "milliseconds");
    baseRegistry.register(metadata, gauge);

    long actualUptime /* in ms */ = ManagementFactory.getRuntimeMXBean().getUptime();
    double actualUptimeInSeconds = actualUptime / 1000.0;

    StringBuilder out = exporter.exportOneMetric(MetricRegistry.Type.BASE, new MetricID("jvm.uptime"));
    assertNotNull(out);

    double valueFromOpenMetrics = -1;
    for (String line : out.toString().split(System.getProperty("line.separator"))) {
        if (line.startsWith("base_jvm_uptime_seconds")) {
            valueFromOpenMetrics /* in seconds */ = Double
                    .valueOf(line.substring("base:jvm_uptime_seconds".length()).trim());
        }
    }
    assertTrue("Value should not be -1", valueFromOpenMetrics != -1);
    assertTrue(valueFromOpenMetrics >= actualUptimeInSeconds);
}
 

/**
 * Given a Gauge with unit=MINUTES,
 * check that the statistics from OpenMetricsExporter will be presented in MINUTES.
 */
@Test
public void gauge_json() {
    MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.APPLICATION);
    Metadata metadata = Metadata.builder()
            .withName("gauge1")
            .withType(MetricType.GAUGE)
            .withUnit(MetricUnits.MINUTES)
            .build();
    Gauge<Long> gaugeInstance = () -> 3L;
    registry.register(metadata, gaugeInstance);

    JsonExporter exporter = new JsonExporter();
    String exported = exporter.exportOneMetric(MetricRegistry.Type.APPLICATION, new MetricID("gauge1")).toString();

    JsonObject json = Json.createReader(new StringReader(exported)).read().asJsonObject();
    assertEquals(3, json.getInt("gauge1"));
}
 

/**
 * Given a Gauge with unit=MINUTES,
 * check that the statistics from OpenMetricsExporter will be presented in SECONDS.
 */
@Test
public void gauge_openMetrics() {
    MetricRegistry registry = MetricRegistries.get(MetricRegistry.Type.APPLICATION);
    Metadata metadata = Metadata.builder()
            .withName("gauge1")
            .withType(MetricType.GAUGE)
            .withUnit(MetricUnits.MINUTES)
            .build();
    Gauge<Long> gaugeInstance = () -> 3L;
    registry.register(metadata, gaugeInstance);

    OpenMetricsExporter exporter = new OpenMetricsExporter();
    String exported = exporter.exportOneMetric(MetricRegistry.Type.APPLICATION, new MetricID("gauge1")).toString();

    Assert.assertThat(exported, containsString("application_gauge1_seconds 180.0"));
}
 

private boolean isSameType(Metric metricInstance, MetricType type) {
    switch (type) {
        case CONCURRENT_GAUGE:
            return metricInstance instanceof ConcurrentGauge;
        case GAUGE:
            return metricInstance instanceof Gauge;
        case HISTOGRAM:
            return metricInstance instanceof Histogram;
        case TIMER:
            return metricInstance instanceof Timer;
        case METERED:
            return metricInstance instanceof Meter;
        case COUNTER:
            return metricInstance instanceof Counter;
        case SIMPLE_TIMER:
            return metricInstance instanceof SimpleTimer;
        default:
            throw new IllegalArgumentException();
    }
}
 

private MetricType metricTypeFromClass(Class<?> in) {
    if (in.equals(Counter.class)) {
        return MetricType.COUNTER;
    } else if (in.equals(Gauge.class)) {
        return MetricType.GAUGE;
    } else if (in.equals(ConcurrentGauge.class)) {
        return MetricType.CONCURRENT_GAUGE;
    } else if (in.equals(Meter.class)) {
        return MetricType.METERED;
    } else if (in.equals(Timer.class)) {
        return MetricType.TIMER;
    } else if (in.equals(SimpleTimer.class)) {
        return MetricType.SIMPLE_TIMER;
    } else if (in.equals(Histogram.class)) {
        return MetricType.HISTOGRAM;
    }
    return null;
}
 

/**
 * Calls {@code baseline()} on all relevant metrics.
 * <p>
 * Extracts all of the {@code Counter} and {@code Gauge} metrics from
 * {@link MetricDefinition} and calls {@link CounterMetric#baseline()} or
 * {@link GaugeMetric#baseline()} on them.
 * <p>
 * This allows us to check how they've changed later in the test using the
 * {@code CounterMetric.delta()} or {@code GaugeMetric.delta()} methods, without
 * having to explicitly baseline every metric ourselves up front.
 */
public void baselineMetrics() {
    for (MetricDefinition definition : MetricDefinition.values()) {
        for (TagValue[] tags : getTagCombinations(definition.getTagClasses())) {
            MetricID id = getMetricId(definition, tags);
            if (definition.getMetricClass() == Counter.class) {
                getCounterMetric(id).baseline();
            }
            if (definition.getMetricClass() == Gauge.class) {
                getGaugeMetric(id).baseline();
            }
        }
    }
}
 

@Test
public void testManualGauge() {
    MetricID gaugeMetricID = new MetricID("tck.gaugetest.gaugemanual");
    
    Gauge<?> gauge = metrics.getGauge(gaugeMetricID);
    Assert.assertNull(gauge);
    gaugeMe();
    gauge = metrics.getGauge(gaugeMetricID);
    
    Assert.assertEquals(0, gauge.getValue());
    Assert.assertEquals(1, gauge.getValue());
}
 

@Test
@InSequence(2)
public void callGaugeAfterSetterCall() {
    @SuppressWarnings("unchecked")
    Gauge<Long> gauge = (Gauge<Long>) registry.getGauge(gaugeMID);
    assertThat("Gauge is not registered correctly", gauge, notNullValue());

    // Call the setter method and assert the gauge is up-to-date
    long value = Math.round(Math.random() * Long.MAX_VALUE);
    bean.setGauge(value);
    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo(value)));
}
 

@Test
@InSequence(1)
public void gaugeCalledWithDefaultValue() {
    @SuppressWarnings("unchecked")
    Gauge<Long> gauge = (Gauge<Long>) registry.getGauge(gaugeMID);
    assertThat("Gauge is not registered correctly", gauge, notNullValue());

    // Make sure that the gauge has the expected value
    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo(0L)));
}
 

private void gaugeRegister(String name, Supplier<Long> supplier) {
    MetricID metricID = new MetricID(name);
    Gauge<?> gauge = registry.getGauges().get(metricID);
    if (gauge == null) {
        synchronized (operation) {
            gauge = registry.getGauges().get(metricID);
            if (gauge == null) {
                registry.register(name, (Gauge<Long>) supplier::get);
            }
        }
    }
}
 

@Test
@InSequence(1)
public void gaugesCalledWithDefaultValues() {
    @SuppressWarnings("unchecked")
    Gauge<Long> parentGauge = (Gauge<Long>) registry.getGauge(parentMID);
    @SuppressWarnings("unchecked")
    Gauge<Long> childGauge = (Gauge<Long>) registry.getGauge(childMID);
    assertThat("Gauges are not registered correctly", parentGauge, notNullValue());
    assertThat("Gauges are not registered correctly", childGauge, notNullValue());

    // Make sure that the gauge has the expected value
    assertThat("Gauge values are incorrect", Arrays.asList(parentGauge.getValue(), childGauge.getValue()), contains(0L, 0L));
}
 

private void micrometerJvmClassLoaderMetrics(MetricRegistry registry) {
    // The ClassLoadingMXBean can be used in native mode, but it only returns zeroes, so there's no point in including such metrics.
    if (!ImageInfo.inImageCode()) {
        ClassLoadingMXBean classLoadingBean = ManagementFactory.getClassLoadingMXBean();

        registry.register(
                new ExtendedMetadataBuilder()
                        .withName("jvm.classes.loaded")
                        .withType(MetricType.GAUGE)
                        .withUnit("classes")
                        .withDescription("The number of classes that are currently loaded in the Java virtual machine")
                        .withOpenMetricsKeyOverride("jvm_classes_loaded_classes")
                        .build(),
                new Gauge() {
                    @Override
                    public Number getValue() {
                        return classLoadingBean.getLoadedClassCount();
                    }
                });

        registry.register(
                new ExtendedMetadataBuilder()
                        .withName("jvm.classes.unloaded")
                        .withType(MetricType.COUNTER)
                        .withUnit("classes")
                        .withDescription(
                                "The total number of classes unloaded since the Java virtual machine has started execution")
                        .withOpenMetricsKeyOverride("jvm_classes_unloaded_classes_total")
                        .build(),
                new GetCountOnlyCounter() {
                    @Override
                    public long getCount() {
                        return classLoadingBean.getUnloadedClassCount();
                    }
                });
    }
}
 

/**
 * Mimics Uptime metrics from Micrometer. Most of the logic here is basically copied from
 * {@link <a href=
 * "https://github.com/micrometer-metrics/micrometer/blob/master/micrometer-core/src/main/java/io/micrometer/core/instrument/binder/system/UptimeMetrics.java">Micrometer
 * Uptime metrics</a>}.
 * 
 * @param registry
 */
private void micrometerRuntimeMetrics(MetricRegistry registry) {
    RuntimeMXBean runtimeMXBean = ManagementFactory.getRuntimeMXBean();

    registry.register(
            new ExtendedMetadataBuilder()
                    .withName("process.runtime")
                    .withType(MetricType.GAUGE)
                    .withUnit(MetricUnits.MILLISECONDS)
                    .withDescription("The uptime of the Java virtual machine")
                    .skipsScopeInOpenMetricsExportCompletely(true)
                    .build(),
            new Gauge() {
                @Override
                public Number getValue() {
                    return runtimeMXBean.getUptime();
                }
            });
    registry.register(
            new ExtendedMetadataBuilder()
                    .withName("process.start.time")
                    .withType(MetricType.GAUGE)
                    .withUnit(MetricUnits.MILLISECONDS)
                    .withDescription("Start time of the process since unix epoch.")
                    .skipsScopeInOpenMetricsExportCompletely(true)
                    .build(),
            new Gauge() {
                @Override
                public Number getValue() {
                    return runtimeMXBean.getStartTime();
                }
            });
}
 

@Test
@InSequence(1)
public void cachedMethodNotCalledYet() {
    assertThat("Metrics are not registered correctly", registry.getMetricIDs(),
        contains(cacheHitsMID, callsMID, hitsMID));
    Timer calls = registry.getTimer(callsMID);
    Meter hits = registry.getMeter(hitsMID);
    @SuppressWarnings("unchecked")
    Gauge<Double> gauge = (Gauge<Double>) registry.getGauge(cacheHitsMID);

    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo(((double) hits.getCount() / (double) calls.getCount()))));
}
 

@Produces
@Metric(name = "cache-hits")
Gauge<Double> cacheHitRatioGauge(final @Metric(name = "hits") Meter hits, final @Metric(name = "calls") Timer calls) {
    return new Gauge<Double>() {

        @Override
        public Double getValue() {
            return (double) hits.getCount() / (double) calls.getCount();
        }
    };

}
 

public void gaugeMe() {

        @SuppressWarnings("unchecked")
        Gauge<Long> gauge = (Gauge<Long>) metrics.getGauge(new MetricID("metricTest.test1.gauge"));
        if (gauge == null) {
            gauge = () -> {
                return 19L;
            };

            Metadata metadata = Metadata.builder().withName("metricTest.test1.gauge")
                    .withType(MetricType.GAUGE).withUnit(MetricUnits.GIGABYTES).build();
            metrics.register(metadata, gauge);
        }

    }
 

@InSequence(3)
public void incrementCountersFromInjection(@Metric(name = "ratioGauge", absolute = true) Gauge<Double> gauge,
                                           @Metric(name = "counter1", absolute = true) Counter counter1,
                                           @Metric(name = "counter2", absolute = true) Counter counter2) {
    counter1.inc(Math.round(Math.random() * Integer.MAX_VALUE));
    counter2.inc(Math.round(Math.random() * Integer.MAX_VALUE));

    assertThat("Gauge value is incorrect", gauge.getValue(), is(equalTo(((double) counter1.getCount()) / ((double) counter2.getCount()))));

    @SuppressWarnings("unchecked")
    Gauge<Double> gaugeFromRegistry = (Gauge<Double>) registry.getGauge(new MetricID("ratioGauge"));
    assertThat("Gauge is not registered correctly", gaugeFromRegistry, notNullValue());

    assertThat("Gauge values from registry and injection do not match", gauge.getValue(), is(equalTo(gaugeFromRegistry.getValue())));
}