Sample application MicroProfile-Opentracing

This repository holds the sample application for illustrating the usage of MicroProfile-Opentracing with Thorntail, Quarkus and Wildfly, and is part of an article you find at https://www.gepardec.com/blog/ among other interesting articles.

Description

This sample application implements a simple JEE application which uses MicroProfile-Opentracing to trace its rest resources as well as rest clients and runs as a microservice with Thorntail, Quarkus and as a WAR deployment in Wildfly.

Technologies

• Java JDK 11

• wildfly-maven-plugin

• thorntail-maven-plugin

• MicroProfile-Config

• MicroProfile-Rest-Client

• MicroProfile-Opentracing

• Thorntail

• Quarkus

• Wildfly 18.0.0.Final

Resources

• ./thorntail-props.yaml
  The Thorntail configuration file which defines the rest client configuration properties

• ./src/main/resources/application.properties
  The Quarkus configuration file which defines the jaeger and rest client configuration properties

• ./src/main/resources/project-defaults.yaml
  The Thorntail configuration file which defines the jaeger and rest client configuration properties

• ./wildfly.properties
  The properties file which defines the jaeger and rest client configuration properties

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/ExternalRestResource.java
  The type safe rest client interface for the external rest resources

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/RestResource.java
  The rest resource which uses the injectable ExternalResource instance which uses the ClientTracingFeature without modifications

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/CustomRestResource.java
  The rest resource which builds the ExternalResource instance via the builder and which uses a custom built ClientTracingFeature which uses the ClientSpanDecorator

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/ClientSpanDecorator.java
  The client side span decorator which adds additional information on the span

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/ServerSpanDecorator.java
  The server side span decorator which adds additional information on the span

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/TracerFactory.java
  The tracer factory which creates the tracer and registers it on the GlobalTracer

• ./src/main/resources/io.opentracing.contrib.tracerresolver.TracerFactory
  The file discovered by SPI which registers the TracerFactory

• ./src/main/java/com/gepardec/samples/microprofile/opentracing/TracingInitializerFeature.java
  The JAX-RS dynamic feature which uses the ServerSpanDecorator

• ./pom.xml
  The pom.xml defining the Thorntail, Quarkus and Wildfly configurations separated by profiles

How to build

Thorntail microservice

mvn clean install -Pthorntail

Quarkus microservice

mvn clean install -Pquarkus

Wildfly WAR deployment

mvn clean install -Pwildfly

How to run

Start Thorntail microservice

mvn thorntail:run -Pthorntail

Start Quarkus microservice

java "-Djava.net.preferIPv4Stack=true" -jar target\microprofile-opentracing-0.0.1-SNAPSHOT-runner.jar

Tip	Normally the maven goal quarkus:dev should start the application as well but it fails with ClassNotFoundException (org/jboss/logging/Logger). I’m not familiar with Qurakus yet, so we run the jar instead.

Start/Configure/Deploy Wildfly

mvn wildfly:run -Pwildfly

Prepare test

This sample application requires a Jaeger instance running on localhost:6831 where the traces are sent.

Start Jaeger with docker

docker run -p 6831:6831/udp -p 16686:16686 --name jaeger-local jaegertracing/all-in-one:latest

How to test

If you use Intellij then you can use the test.http file for testing the rest endpoints.
Otherwise see the following available endpoints and use the tool of your choice.

With injectable rest client

GET call to external resource

GET http://127.0.0.1:8080/get

POST call to external resource

POST http://127.0.0.1:8080/post

PATCH call to external resource

PATCH http://127.0.0.1:8080/patch

DELETE call to external resource

DELETE http://127.0.0.1:8080/delete

With custom built rest client

GET call to external resource

GET http://127.0.0.1:8080/custom/get

POST call to external resource

POST http://127.0.0.1:8080/custom/post

PATCH call to external resource

PATCH http://127.0.0.1:8080/custom/patch

DELETE call to external resource

DELETE http://127.0.0.1:8080/custom/delete