Add opentelemetry dependency and configuration

README.md

@@ -13,6 +13,62 @@ You can run your application in dev mode that enables live coding using:
 
 > **_NOTE:_**  Quarkus now ships with a Dev UI, which is available in dev mode only at http://localhost:8080/q/dev/.
 
+## OpenTelemetry and Metrics
+
+This application is instrumented with OpenTelemetry and exposes metrics in Prometheus format.
+
+### Metrics Endpoint
+
+Once the application is running, metrics are available at:
+```
+http://localhost:8080/q/metrics
+```
+
+This endpoint provides:
+- **HTTP metrics**: Request count, duration, and status codes
+- **JVM metrics**: Memory usage, thread count, garbage collection statistics
+- **Application metrics**: Custom LRA coordinator metrics
+
+### Example Usage
+
+To view metrics in your browser or with curl:
+```shell script
+curl http://localhost:8080/q/metrics
+```
+
+### Integration with Prometheus
+
+To scrape metrics with Prometheus, add the following job to your `prometheus.yml`:
+```yaml
+scrape_configs:
+  - job_name: 'lra-coordinator'
+    metrics_path: '/q/metrics'
+    static_configs:
+      - targets: ['localhost:8080']
+```
+
+### OpenTelemetry Configuration
+
+The application is configured with:
+- Service name: `lra-coordinator`
+- Traces enabled: Yes
+- Metrics enabled: Yes
+
+Additional OpenTelemetry configuration can be modified in `src/main/resources/application.properties`.
+
+### Grafana Dev Service (Optional)
+
+For a fully integrated observability stack in dev mode (Grafana, Loki, Tempo, Prometheus), you can add the following dependency to your `pom.xml`:
+```xml
+<dependency>
+    <groupId>io.quarkus</groupId>
+    <artifactId>quarkus-observability-devservices-lgtm</artifactId>
+    <scope>provided</scope>
+</dependency>
+```
+
+This will automatically start a Grafana LGTM container when running in dev mode, giving you access to a pre-configured Grafana dashboard to visualize metrics, logs, and traces.
+
 ## Packaging and running the application
 
 The application can be packaged using:

pom.xml

@@ -62,6 +62,24 @@
       <groupId>io.quarkus</groupId>
       <artifactId>quarkus-container-image-docker</artifactId>
     </dependency>
+    <dependency>
+      <groupId>io.quarkus</groupId>
+      <artifactId>quarkus-opentelemetry</artifactId>
+    </dependency>
+	<dependency>
+	    <groupId>io.quarkus</groupId>
+	    <artifactId>quarkus-micrometer-registry-prometheus</artifactId>
+	</dependency>
+    <dependency>
+      <groupId>io.quarkus</groupId>
+      <artifactId>quarkus-junit5</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>io.rest-assured</groupId>
+      <artifactId>rest-assured</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
   <build>
     <plugins>

src/main/resources/application.properties

@@ -20,3 +20,14 @@ quarkus.index-dependency.microprofile-lra-api.artifact-id=microprofile-lra-api
 
 quarkus.index-dependency.lra-service-base.group-id=org.jboss.narayana.lra
 quarkus.index-dependency.lra-service-base.artifact-id=lra-service-base
+
+# OpenTelemetry
+quarkus.otel.service.name=lra-coordinator
+quarkus.otel.traces.enabled=true
+quarkus.otel.metrics.enabled=true
+quarkus.otel.logs.enabled=true
+
+# Metrics endpoint
+quarkus.micrometer.export.prometheus.enabled=true
+quarkus.micrometer.binder.http-server.enabled=true
+quarkus.micrometer.binder.jvm.enabled=true

src/test/java/org/jboss/narayana/rts/OpenTelemetryEndpointTest.java

@@ -0,0 +1,30 @@
+package org.jboss.narayana.rts;
+
+import io.quarkus.test.junit.QuarkusTest;
+import org.junit.jupiter.api.Test;
+
+import static io.restassured.RestAssured.given;
+import static org.hamcrest.Matchers.containsString;
+
+@QuarkusTest
+class OpenTelemetryEndpointTest {
+
+    @Test
+    void metricsEndpointReturnsPrometheusData() {
+        given()
+            .when().get("/q/metrics")
+            .then()
+            .statusCode(200)
+            .contentType(containsString("openmetrics-text"))
+            .body(containsString("jvm_memory"));
+    }
+
+    @Test
+    void metricsEndpointContainsHttpServerMetrics() {
+        given()
+            .when().get("/q/metrics")
+            .then()
+            .statusCode(200)
+            .body(containsString("http_server"));
+    }
+}

src/test/resources/application.properties

@@ -0,0 +1,3 @@
+# Disable OTLP exporter in tests (no collector available)
+quarkus.otel.exporter.otlp.traces.endpoint=http://localhost:4317
+quarkus.otel.sdk.disabled=true