updated helm chart to use version 6.1.0 of the image

charts/hapi-fhir-jpaserver/README.md.gotmpl

@@ -18,8 +18,8 @@ helm install --render-subchart-notes hapi-fhir-jpaserver hapifhir/hapi-fhir-jpas
 
 ## Development
 
-To update the Helm chart when a new version of the `hapiproject/hapi` image is released, the [Chart.yaml](Chart.yaml)'s
-`appVersion` and `version` fields need to be updated accordingly. Afterwards, re-generate the [README.md](README.md)
+To update the Helm chart when a new version of the `hapiproject/hapi` image is released, [values.yaml](values.yaml) `image.tag` and the [Chart.yaml](Chart.yaml)'s
+`version` and optionally the `appVersion` field on major releases need to be updated. Afterwards, re-generate the [README.md](README.md)
 by running:
 
 ```sh
@@ -28,4 +28,53 @@ INFO[2021-11-20T12:38:04Z] Found Chart directories [charts/hapi-fhir-jpaserver]
 INFO[2021-11-20T12:38:04Z] Generating README Documentation for chart /usr/src/app/charts/hapi-fhir-jpaserver
 ```
 
+## Enable Distributed Tracing based on the OpenTelemtry Java Agent
+
+The container image includes the [OpenTelemetry Java agent JAR](https://github.com/open-telemetry/opentelemetry-java-instrumentation)
+which can be used to enable distributed tracing. It can be configured entirely using environment variables,
+see <https://opentelemetry.io/docs/instrumentation/java/automatic/agent-config/> for details.
+
+Here's an example setup deploying [Jaeger](https://www.jaegertracing.io/) as a tracing backend:
+
+```sh
+# required by the Jaeger Operator
+kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.9.1/cert-manager.yaml
+kubectl create namespace observability
+kubectl create -f https://github.com/jaegertracing/jaeger-operator/releases/download/v1.37.0/jaeger-operator.yaml -n observability
+
+cat <<EOF | kubectl apply -n observability -f -
+# simple, all-in-one Jaeger installation. Not suitable for production use.
+apiVersion: jaegertracing.io/v1
+kind: Jaeger
+metadata:
+  name: simplest
+EOF
+```
+
+Use this chart's `extraEnv` value to set the required environment variables:
+
+```yaml
+extraEnv:
+  - name: JAVA_TOOL_OPTIONS
+    value: "-javaagent:/app/opentelemetry-javaagent.jar"
+  - name: OTEL_METRICS_EXPORTER
+    value: "none"
+  - name: OTEL_LOGS_EXPORTER
+    value: "none"
+  - name: OTEL_TRACES_EXPORTER
+    value: "jaeger"
+  - name: OTEL_SERVICE_NAME
+    value: "hapi-fhir-jpaserver"
+  - name: OTEL_EXPORTER_JAEGER_ENDPOINT
+    value: "http://simplest-collector.observability.svc:14250"
+```
+
+Finally, you can open the Jaeger query UI by running:
+
+```sh
+kubectl port-forward -n observability service/simplest-query 16686:16686
+```
+
+and opening <http://localhost:16686/> in your browser.
+
 {{ template "helm-docs.versionFooter" . }}