Quarkus - Using OpenTracing
This guide explains how your Quarkus application can utilize OpenTracing to provide distributed tracing for interactive web applications.
Prerequisites
To complete this guide, you need:
-
less than 15 minutes
-
an IDE
-
JDK 1.8+ installed with
JAVA_HOME
configured appropriately -
Apache Maven 3.6.2+
-
Docker
Architecture
In this guide, we create a straightforward REST application to demonstrate distributed tracing.
Solution
We recommend that you follow the instructions in the next sections and create the application step by step. However, you can skip right to the completed example.
Clone the Git repository: git clone https://github.com/quarkusio/quarkus-quickstarts.git
, or download an archive.
The solution is located in the opentracing-quickstart
directory.
Creating the Maven project
First, we need a new project. Create a new project with the following command:
mvn io.quarkus:quarkus-maven-plugin:1.12.0.Final:create \
-DprojectGroupId=org.acme \
-DprojectArtifactId=opentracing-quickstart \
-DclassName="org.acme.opentracing.TracedResource" \
-Dpath="/hello" \
-Dextensions="resteasy,quarkus-smallrye-opentracing"
cd opentracing-quickstart
This command generates the Maven project with a REST endpoint and imports the smallrye-opentracing
extension, which
includes the OpenTracing support and the default Jaeger tracer.
If you already have your Quarkus project configured, you can add the smallrye-opentracing
extension
to your project by running the following command in your project base directory:
./mvnw quarkus:add-extension -Dextensions="smallrye-opentracing"
This will add the following to your pom.xml
:
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-smallrye-opentracing</artifactId>
</dependency>
Examine the JAX-RS resource
Open the src/main/java/org/acme/opentracing/TracedResource.java
file and see the following content:
package org.acme.opentracing;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import org.jboss.logging.Logger;
@Path("/hello")
public class TracedResource {
private static final Logger LOG = Logger.getLogger(TracedResource.class);
@GET
@Produces(MediaType.TEXT_PLAIN)
public String hello() {
LOG.info("hello");
return "hello";
}
}
Notice that there is no tracing specific code included in the application. By default, requests sent to this endpoint will be traced without any code changes being required. It is also possible to enhance the tracing information. For more information on this, please see the MicroProfile OpenTracing specification.
Create the configuration
There are two ways to configure the Jaeger tracer within the application.
The first approach is by providing the properties within the src/main/resources/application.properties
file:
quarkus.jaeger.service-name=myservice (1)
quarkus.jaeger.sampler-type=const (2)
quarkus.jaeger.sampler-param=1 (3)
quarkus.log.console.format=%d{HH:mm:ss} %-5p traceId=%X{traceId}, parentId=%X{parentId}, spanId=%X{spanId}, sampled=%X{sampled} [%c{2.}] (%t) %s%e%n (4)
1 | If the quarkus.jaeger.service-name property (or JAEGER_SERVICE_NAME environment variable) is not provided then a "no-op" tracer will be configured, resulting in no tracing data being reported to the backend. |
2 | Setup a sampler, that uses a constant sampling strategy. |
3 | Sample all requests. Set sampler-param to somewhere between 0 and 1, e.g. 0.50, if you do not wish to sample all requests. |
4 | Add trace IDs into log message. |
The second approach is to supply the properties as environment variables. These can be specified as jvm.args
as shown in the following section.
Run the application
The first step is to start the tracing system to collect and display the captured traces:
docker run -p 5775:5775/udp -p 6831:6831/udp -p 6832:6832/udp -p 5778:5778 -p 16686:16686 -p 14268:14268 jaegertracing/all-in-one:latest
Now we are ready to run our application. If using application.properties
to configure the tracer:
./mvnw compile quarkus:dev
or if configuring the tracer via environment variables:
./mvnw compile quarkus:dev -Djvm.args="-DJAEGER_SERVICE_NAME=myservice -DJAEGER_SAMPLER_TYPE=const -DJAEGER_SAMPLER_PARAM=1"
Once both the application and tracing system are started, you can make a request to the provided endpoint:
$ curl http://localhost:8080/hello
hello
When the first request has been submitted, the Jaeger tracer within the app will be initialized:
2019-10-16 09:35:23,464 INFO [io.jae.Configuration] (executor-thread-1) Initialized tracer=JaegerTracer(version=Java-0.34.0, serviceName=myservice, reporter=RemoteReporter(sender=UdpSender(), closeEnqueueTimeout=1000), sampler=ConstSampler(decision=true, tags={sampler.type=const, sampler.param=true}), tags={hostname=localhost.localdomain, jaeger.version=Java-0.34.0, ip=127.0.0.1}, zipkinSharedRpcSpan=false, expandExceptionLogs=false, useTraceId128Bit=false)
13:20:11 INFO traceId=1336b2b0a76a96a3, parentId=0, spanId=1336b2b0a76a96a3, sampled=true [or.ac.qu.TracedResource] (executor-thread-63) hello
Then visit the Jaeger UI to see the tracing information.
Hit CTRL+C
to stop the application.
Tracing additional methods
REST endpoints are automatically traced.
If you need to trace additional methods, you can use the org.eclipse.microprofile.opentracing.Traced
annotation at class or method level.
This can be useful to trace incoming requests from non-REST calls (like request coming from a message) or to create spans inside a trace.
Here is an example of a FrancophoneService
which methods are traced.
import javax.enterprise.context.ApplicationScoped;
import org.eclipse.microprofile.opentracing.Traced;
@Traced
@ApplicationScoped
public class FrancophoneService {
public String bonjour() {
return "bonjour";
}
}
the best way to add OpenTracing capability to reactive messaging based applications is by adding the Traced annotation to all incoming methods.
|
Additional instrumentation
The OpenTracing API Contributions project offers additional instrumentation that can be used to add tracing to a large variety of technologies/components.
The instrumentation documented in this section has been tested with Quarkus and works in both standard and native mode.
JDBC
The JDBC instrumentation will add a span for each JDBC queries done by your application, to enable it, add the following dependency to your pom.xml:
<dependency>
<groupId>io.opentracing.contrib</groupId>
<artifactId>opentracing-jdbc</artifactId>
</dependency>
As it uses a dedicated JDBC driver, you must configure your datasource and Hibernate to use it.
quarkus.datasource.db-kind=postgresql
# add ':tracing' to your database URL
quarkus.datasource.jdbc.url=jdbc:tracing:postgresql://localhost:5432/mydatabase
# use the 'TracingDriver' instead of the one for your database
quarkus.datasource.jdbc.driver=io.opentracing.contrib.jdbc.TracingDriver
# configure Hibernate dialect
quarkus.hibernate-orm.dialect=org.hibernate.dialect.PostgreSQLDialect
Kafka
The Kafka instrumentation will add a span for each message sent to or received from a Kafka topic. To enable it, add the following dependency to your pom.xml:
<dependency>
<groupId>io.opentracing.contrib</groupId>
<artifactId>opentracing-kafka-client</artifactId>
<version>${opentracing-kafka.version}</version>
</dependency>
It contains OpenTracing interceptors that must be registered on Kafka producers and consumers.
If you followed the Kafka guide, the interceptors can be added on the generated-price
and the prices
channels as follows:
# Configure the Kafka sink (we write to it)
mp.messaging.outgoing.generated-price.connector=smallrye-kafka
mp.messaging.outgoing.generated-price.topic=prices
mp.messaging.outgoing.generated-price.value.serializer=org.apache.kafka.common.serialization.IntegerSerializer
mp.messaging.outgoing.generated-price.interceptor.classes=io.opentracing.contrib.kafka.TracingProducerInterceptor
# Configure the Kafka source (we read from it)
mp.messaging.incoming.prices.connector=smallrye-kafka
mp.messaging.incoming.prices.value.deserializer=org.apache.kafka.common.serialization.IntegerDeserializer
mp.messaging.incoming.prices.interceptor.classes=io.opentracing.contrib.kafka.TracingConsumerInterceptor
interceptor.classes accept a list of classes separated by a comma.
|
Jaeger Configuration Reference
Configuration property fixed at build time - All other configuration properties are overridable at runtime
Type |
Default |
|
---|---|---|
Defines if the Jaeger extension is enabled. |
boolean |
|
Whether or not metrics are published in case a metrics extension is present. |
boolean |
|
The traces endpoint, in case the client should connect directly to the Collector, like http://jaeger-collector:14268/api/traces |
||
Authentication Token to send as "Bearer" to the endpoint |
string |
|
Username to send as part of "Basic" authentication to the endpoint |
string |
|
Password to send as part of "Basic" authentication to the endpoint |
string |
|
The hostname and port for communicating with agent via UDP |
host:port |
|
Whether the reporter should also log the spans |
boolean |
|
The reporter’s maximum queue size |
int |
|
The reporter’s flush interval |
||
The sampler type (const, probabilistic, ratelimiting or remote) |
string |
|
The sampler parameter (number) |
||
The host name and port when using the remote controlled sampler |
host:port |
|
The service name |
string |
|
A comma separated list of name = value tracer level tags, which get added to all reported spans. The value can also refer to an environment variable using the format ${envVarName:default}, where the :default is optional, and identifies a value to be used if the environment variable cannot be found |
string |
|
Comma separated list of formats to use for propagating the trace context. Defaults to the standard Jaeger format. Valid values are jaeger and b3 |
string |
|
The sender factory class name |
string |
|
Whether the trace context should be logged. |
boolean |
|
About the Duration format
The format for durations uses the standard You can also provide duration values starting with a number.
In this case, if the value consists only of a number, the converter treats the value as seconds.
Otherwise, |