Using OpenTelemetry Metrics
This guide explains how your Quarkus application can utilize OpenTelemetry (OTel) to provide metrics for interactive web applications.
Essa tecnologia é considerada preview. In preview, backward compatibility and presence in the ecosystem is not guaranteed. Specific improvements might require changing configuration or APIs, and plans to become stable are under way. Feedback is welcome on our mailing list or as issues in our GitHub issue tracker. Para obter uma lista completa de possíveis status, consulte nosso FAQ. |
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Pré-requisitos
Para concluir este guia, você precisa:
-
Cerca de 15 minutos
-
Um IDE
-
JDK 17+ installed with
JAVA_HOME
configured appropriately -
Apache Maven 3.9.9
-
Docker e Docker Compose ou Podman e Docker Compose
-
Opcionalmente, o Quarkus CLI se você quiser usá-lo
-
Opcionalmente, Mandrel ou GraalVM instalado e configurado apropriadamente se você quiser criar um executável nativo (ou Docker se você usar uma compilação de contêiner nativo)
Arquitetura
In this guide, we create a straightforward REST application to demonstrate distributed tracing.
Solução
Recomendamos que você siga as instruções nas próximas seções e crie o aplicativo passo a passo. No entanto, você pode pular diretamente para o exemplo completo.
Clone o repositório Git: git clone https://github.com/quarkusio/quarkus-quickstarts.git
, ou baixe um arquivo.
The solution is located in the opentelemetry-quickstart
directory.
Criar o projeto Maven
Primeiro, precisamos de um novo projeto. Crie um novo projeto com o seguinte comando:
Para usuários do Windows:
-
Se estiver usando cmd, (não use barra invertida '\' e coloque tudo na mesma linha)
-
Se estiver usando o Powershell, envolva os parâmetros '-D' entre aspas duplas, por exemplo, '"-DprojectArtifactId=opentelemetry-quickstart"'
This command generates the Maven project and imports the quarkus-opentelemetry
extension,
which includes the default OpenTelemetry support,
and a gRPC span exporter for OTLP.
If you already have your Quarkus project configured, you can add the quarkus-opentelemetry
extension
to your project by running the following command in your project base directory:
quarkus extension add opentelemetry
./mvnw quarkus:add-extension -Dextensions='opentelemetry'
./gradlew addExtension --extensions='opentelemetry'
Isto irá adicionar o seguinte trecho no seu arquivo de build:
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-opentelemetry</artifactId>
</dependency>
implementation("io.quarkus:quarkus-opentelemetry")
Examine the Jakarta REST resource
Create a src/main/java/org/acme/opentelemetry/MetricResource.java
file with the following content:
package org.acme;
import io.opentelemetry.api.metrics.LongCounter;
import io.opentelemetry.api.metrics.Meter;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
import org.jboss.logging.Logger;
@Path("/hello-metrics")
public class MetricResource {
private static final Logger LOG = Logger.getLogger(MetricResource.class);
private final LongCounter counter;
public MetricResource(Meter meter) { (1)
counter = meter.counterBuilder("hello-metrics") (2)
.setDescription("hello-metrics")
.setUnit("invocations")
.build();
}
@GET
@Produces(MediaType.TEXT_PLAIN)
public String hello() {
counter.add(1); (3)
LOG.info("hello-metrics");
return "hello-metrics";
}
}
Quarkus is not currently producing metrics out of the box.
Here we are creating a counter for the number of invocations of the hello()
method.
1 | Constructor injection of the Meter instance. |
2 | Create a LongCounter named hello-metrics with a description and unit. |
3 | Increment the counter by one for each invocation of the hello() method. |
Crie a configuração
The only mandatory configuration for OpenTelemetry Metrics is the one enabling it:
quarkus.otel.metrics.enabled=true
To change any of the default property values, here is an example on how to configure the default OTLP gRPC Exporter within the application, using the src/main/resources/application.properties
file:
quarkus.application.name=myservice (1)
quarkus.otel.metrics.enabled=true (2)
quarkus.otel.exporter.otlp.metrics.endpoint=http://localhost:4317 (3)
quarkus.otel.exporter.otlp.metrics.headers=authorization=Bearer my_secret (4)
1 | All metrics created from the application will include an OpenTelemetry Resource indicating the metrics was created by the myservice application.
If not set, it will default to the artifact id. |
2 | Enable the OpenTelemetry metrics. Must be set at build time. |
3 | gRPC endpoint to send the metrics.
If not set, it will default to http://localhost:4317 . |
4 | Optional gRPC headers commonly used for authentication. |
To configure the connection using the same properties for all signals, please check the base configuration section of the OpenTelemetry guide.
To disable particular parts of OpenTelemetry, you can set the properties listed in this section of the OpenTelemetry guide.
Executar o aplicativo
First we need to start a system to visualise the OpenTelemetry data.
See the data
Grafana-OTel-LGTM Dev Service
You can use the Grafana-OTel-LGTM devservice.
This Dev service includes a Grafana for visualizing data, Loki to store logs, Tempo to store traces and Prometheus to store metrics. Also provides and OTel collector to receive the data.
Logging exporter
You can output all metrics to the console by setting the exporter to logging
in the application.properties
file:
quarkus.otel.metrics.exporter=logging (1)
quarkus.otel.metric.export.interval=10000ms (2)
1 | Set the exporter to logging .
Normally you don’t need to set this.
The default is cdi . |
2 | Set the interval to export the metrics.
The default is 1m , which is too long for debugging. |
Also add this dependency to your project:
<dependency>
<groupId>io.opentelemetry</groupId>
<artifactId>opentelemetry-exporter-logging</artifactId>
</dependency>
Start the application
Now we are ready to run our application.
If using application.properties
to configure the tracer:
quarkus dev
./mvnw quarkus:dev
./gradlew --console=plain quarkusDev
or if configuring the OTLP gRPC endpoint via JVM arguments:
quarkus dev -Djvm.args="-Dquarkus.otel.exporter.otlp.endpoint=http://localhost:4317"
./mvnw quarkus:dev -Djvm.args="-Dquarkus.otel.exporter.otlp.endpoint=http://localhost:4317"
./gradlew --console=plain quarkusDev -Djvm.args="-Dquarkus.otel.exporter.otlp.endpoint=http://localhost:4317"
With the OpenTelemetry Collector, the Jaeger system and the application running, you can make a request to the provided endpoint:
$ curl http://localhost:8080/hello-metrics
hello-metrics
When using the logger exporter, metrics will be printed to the console. This is a pretty printed example:
{
"metric": "ImmutableMetricData",
"resource": {
"Resource": {
"schemaUrl": null,
"attributes": { (1)
"host.name": "myhost",
"service.name": "myservice ",
"service.version": "1.0.0-SNAPSHOT",
"telemetry.sdk.language": "java",
"telemetry.sdk.name": "opentelemetry",
"telemetry.sdk.version": "1.32.0",
"webengine.name": "Quarkus",
"webengine.version": "999-SNAPSHOT"
}
},
"instrumentationScopeInfo": {
"InstrumentationScopeInfo": { (2)
"name": "io.quarkus.opentelemetry",
"version": null,
"schemaUrl": null,
"attributes": {}
}
},
"name": "hello-metrics", (3)
"description": "hello-metrics",
"unit": "invocations",
"type": "LONG_SUM",
"data": {
"ImmutableSumData": {
"points": [
{
"ImmutableLongPointData": {
"startEpochNanos": 1720622136612378000,
"epochNanos": 1720622246618331000,
"attributes": {},
"value": 3, (4)
"exemplars": [ (5)
{
"ImmutableLongExemplarData": {
"filteredAttributes": {},
"epochNanos": 1720622239362357000,
"spanContext": {
"ImmutableSpanContext": {
"traceId": "d91951e50b0641552a76889c5356467c",
"spanId": "168af8b7102d0556",
"traceFlags": "01",
"traceState": "ArrayBasedTraceState",
"entries": [],
"remote": false,
"valid": true
},
"value": 1
}
}
}
]
}
}
],
"monotonic": true,
"aggregationTemporality": "CUMULATIVE"
}
}
}
}
1 | Resource attributes common to all telemetry data. |
2 | Instrumentation scope is allways io.quarkus.opentelemetry |
3 | The name, description and unit of the metric you defined in the constructor of the MetricResource class. |
4 | The value of the metric. 3 invocations were made until now. |
5 | Exemplars additional tracing information about the metric. In this case, the traceId and spanId of one os the request that triggered the metric, since it was last sent. |
Hit CTRL+C
or type q
to stop the application.
Create your own metrics
OpenTelemetry Metrics vs Micrometer Metrics
Metrics are single numerical measurements, often have additional data captured with them. This ancillary data is used to group or aggregate metrics for analysis.
Pretty much like in the Quarkus Micrometer extension, you can create your own metrics using the OpenTelemetry API and the concepts are analogous.
The OpenTelemetry API provides a Meter
interface to create metrics instead of a Registry.
The Meter
interface is the entry point for creating metrics.
It provides methods to create counters, gauges, and histograms.
Attributes can be added to metrics to add dimensions, pretty much like tags in Micrometer.
Obtain a reference to the Meter
Use one of the following methods to obtain a reference to a Meter:
Use CDI Constructor injection
@Path("/hello-metrics")
public class MetricResource {
private final Meter meter;
public MetricResource(Meter meter) {
this.meter = meter;
}
}
Pretty much like in the example above.
Counters
Counters can be used to measure non-negative, increasing values.
LongCounter counter = meter.counterBuilder("hello-metrics") (1)
.setDescription("hello-metrics") // optional
.setUnit("invocations") // optional
.build();
counter.add(1, (2)
Attributes.of(AttributeKey.stringKey("attribute.name"), "attribute value")); // optional (3)
1 | Create a LongCounter named hello-metrics with a description and unit. |
2 | Increment the counter by one. |
3 | Add an attribute to the counter.
This will create a dimension called attribute.name with value attribute value . |
Each unique combination of metric name and dimension produces a unique time series. Using an unbounded set of dimensional data (many different values like a userId) can lead to a "cardinality explosion", an exponential increase in the creation of new time series. Avoid! |
OpenTelemetry provides many other types of Counters: LongUpDownCounter
, DoubleCounter
, DoubleUpDownCounter
and also Observable, async counters like ObservableLongCounter
, ObservableDoubleCounter
, ObservableLongUpDownCounter
and ObservableDoubleUpDownCounter
.
For more details please refer to the OpenTelemetry Java documentation about Counters.
Gauges
Observable Gauges should be used to measure non-additive values. A value that can increase or decrease over time, like the speedometer on a car. Gauges can be useful when monitoring the statistics for a cache or collection.
With this metric you provide a function to be periodically probed by a callback. The value returned by the function is the value of the gauge.
The default gauge records Double
values, but if you want to record Long
values, you can use
meter.gaugeBuilder("jvm.memory.total") (1)
.setDescription("Reports JVM memory usage.")
.setUnit("byte")
.ofLongs() (2)
.buildWithCallback( (3)
result -> result.record(
Runtime.getRuntime().totalMemory(), (4)
Attributes.empty())); // optional (5)
1 | Create a Gauge named jvm.memory.total with a description and unit. |
2 | If you want to record Long values you need this builder method because the default gauge records Double values. |
3 | Build the gauge with a callback. An imperative builder is also available. |
4 | Register the function to call to get the value of the gauge. |
5 | No added attributes, this time. |
Histograms
Histograms are synchronous instruments used to measure a distribution of values over time. It is intended for statistics such as histograms, summaries, and percentile. The request duration and response payload size are good uses for a histogram.
On this section we have a new class, the HistogramResource
that will create a LongHistogram
.
package org.acme;
import io.opentelemetry.api.common.AttributeKey;
import io.opentelemetry.api.common.Attributes;
import io.opentelemetry.api.metrics.LongHistogram;
import io.opentelemetry.api.metrics.Meter;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
import org.jboss.logging.Logger;
import java.util.Arrays;
@Path("/roll-dice")
public class HistogramResource {
private static final Logger LOG = Logger.getLogger(HistogramResource.class);
private final LongHistogram rolls;
public HistogramResource(Meter meter) {
rolls = meter.histogramBuilder("hello.roll.dice") (1)
.ofLongs() (2)
.setDescription("A distribution of the value of the rolls.")
.setExplicitBucketBoundariesAdvice(Arrays.asList(1L, 2L, 3L, 4L, 5L, 6L, 7L)) (3)
.setUnit("points")
.build();
}
@GET
@Produces(MediaType.TEXT_PLAIN)
public String helloGauge() {
var roll = roll();
rolls.record(roll, (4)
Attributes.of(AttributeKey.stringKey("attribute.name"), "value")); (5)
LOG.info("roll-dice: " + roll);
return "" + roll;
}
public long roll() {
return (long) (Math.random() * 6) + 1;
}
}
1 | Create a LongHistogram named hello.roll.dice with a description and unit. |
2 | If you want to record Long values you need this builder method because the default histogram records Double values. |
3 | Set the explicit bucket boundaries for the histogram. The boundaries are inclusive. |
4 | Record the value of the roll. |
5 | Add an attribute to the histogram.
This will create a dimension called attribute.name with value value . |
Beware of cardinality explosion. |
We can invoke the endpoint with a curl command.
$ curl http://localhost:8080/roll-dice
2
If we execute 4 consecutive requests, with results 2,2,3 and 4 this will produce the following output.
The Resource
and InstrumentationScopeInfo
data are ignored for brevity.
//...
name=hello.roll.dice,
description=A distribution of the value of the rolls., (1)
unit=points,
type=HISTOGRAM,
data=ImmutableHistogramData{
aggregationTemporality=CUMULATIVE, (2)
points=[
ImmutableHistogramPointData{
getStartEpochNanos=1720632058272341000,
getEpochNanos=1720632068279567000,
getAttributes={attribute.name="value"}, (3)
getSum=11.0, (4)
getCount=4, (5)
hasMin=true,
getMin=2.0, (6)
hasMax=true,
getMax=4.0, (7)
getBoundaries=[1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0], (8)
getCounts=[0, 2, 1, 1, 0, 0, 0, 0], (9)
getExemplars=[ (10)
ImmutableDoubleExemplarData{
filteredAttributes={},
epochNanos=1720632063049392000,
spanContext=ImmutableSpanContext{
traceId=a22b43a600682ca7320516081eca998b,
spanId=645aa49f219181d0,
traceFlags=01,
traceState=ArrayBasedTraceState{entries=[]},
remote=false,
valid=true
},
value=2.0 (11)
},
//... exemplars for values 3 and 4 omitted for brevity
]
}
]
}
1 | The name, description and unit of the metric you defined in the constructor of the HistogramResource class. |
2 | The aggregation temporality of the histogram. |
3 | The attribute added to the histogram when the values were recorded. |
4 | The sum of the values recorded. |
5 | The number of values recorded. |
6 | The minimum value recorded. |
7 | The maximum value recorded. |
8 | The explicit bucket boundaries for the histogram. |
9 | The number of values recorded in each bucket. |
10 | The list of exemplars with tracing data for the values recorded. We only show 1 of 3 exemplars for brevity. |
11 | One of the 2 calls made with the value 2. |
Differences with the Micrometer API
-
Timers and Distribution Summaries are not available in the OpenTelemetry API. Instead, use Histograms.
-
The OpenTelemetry API does not define annotations for metrics like Micrometer’s
@Counted
,@Timed
or@MeterTag
. You need to manually create the metrics. -
OpenTelemetry uses their own Semantic Conventions to name metrics and attributes.
Resource
See the main OpenTelemetry Guide resources section.
Additional instrumentation
Automatic metrics are not yet provided by the Quarkus OpenTelemetry extension. We plan to bridge the existing Quarkus Micrometer extension metrics to OpenTelemetry in the future.
Exporters
See the main OpenTelemetry Guide exporters section.
OpenTelemetry Configuration Reference
See the main OpenTelemetry Guide configuration reference.