Spring PetClinic Sample Application

Understanding the Spring Petclinic application with a few diagrams

See the presentation here

Run Petclinic locally

This is a modified version of Petclinic and includes two opentelemetry dependencies: opentelemetry-spring-boot-starter and opentelemetry-jdbc. To run this sample locally you must either: A) remove these dependencies B) include -Dotel.sdk.disabled=true as a JVM parameter or C) start up an opentelmetry collector locally. You may follow instructions from the dockerized-otel-agent branch for option C.

git clone https://github.com/spring-projects/spring-petclinic.git
cd spring-petclinic
./mvnw package
java -jar target/*.jar

You can then access the Petclinic at http://localhost:8080/.

Deploy to Azure Container Apps

Azure CLI setup

Check your Azure CLI version and upgrade to the required version if needed.

az --version
az upgrade

Install or update the Azure Application Insights and Azure Container Apps extensions.

az extension add -n application-insights --upgrade --allow-preview true
az extension add --name containerapp --upgrade --allow-preview true

Sign in to Azure CLI if you haven't already done so.

az login

Set the default subscription to use.

az account set --subscription "<subscription-id>"

Register the Microsoft.App and Microsoft.OperationalInsights namespaces if they're not already registered in your Azure subscription.

az provider register --namespace Microsoft.App
az provider register --namespace Microsoft.OperationalInsights

Define variables

Please replace placeholder values in <> with your own.

UNIQUE_VALUE=pc-$(date +%s)
LOCATION=eastus

RESOURCE_GROUP_NAME=${UNIQUE_VALUE}rg
ACA_ENV=${UNIQUE_VALUE}env
APP_INSIGHTS=${UNIQUE_VALUE}appinsights
CONFIG_SERVER=springconfigserver
CONFIG_SERVER_GIT_URI="https://github.com/seanli1988/petclinic.git"
ACA_AI_NAME=${UNIQUE_VALUE}ai
ACA_PETCLINIC_NAME=${UNIQUE_VALUE}petclinic
WORKING_DIR=$(pwd)

Create an Azure Container Apps Environment

Create a resource group and an Azure Container Apps environment.

az group create \
    -n $RESOURCE_GROUP_NAME \
    -l ${LOCATION}

az containerapp env create \
    --resource-group $RESOURCE_GROUP_NAME \
    --location $LOCATION \
    --name $ACA_ENV

Set up a managed Config Server for Spring microservices

Azure Container Apps provides a managed Config Server for Spring microservices. The Config Server is a centralized configuration service that serves configuration data to client applications.

Create a Config Server and configure it to use a Git repository as the backend.

az containerapp env java-component config-server-for-spring create \
  --environment $ACA_ENV \
  --resource-group $RESOURCE_GROUP_NAME \
  --name $CONFIG_SERVER \
  --configuration spring.cloud.config.server.git.uri=$CONFIG_SERVER_GIT_URI

Deploy PetClinic app

The PetClinic app talks to PetClinic AI service. Follow instructions below to deploy it on ACA.

First, prepare the source code for PetClinic app by cloning the repository.

cd $WORKING_DIR
git clone git@github.com:seanli1988/petclinic.git
cd petclinic

Next, build and deploy the PetClinic app to Azure Container Apps.

# Build the artifact
mvn clean package -DskipTests=true

# Deploy the artifact to ACA and bind to config server
az containerapp create \
    --resource-group $RESOURCE_GROUP_NAME \
    --name $ACA_PETCLINIC_NAME \
    --environment $ACA_ENV \
    --artifact ./target/spring-petclinic-3.2.0-SNAPSHOT.jar \
    --target-port 8080 \
    --ingress 'external' \
    --env-vars \
        PETCLINIC_AI_HOST=http://${ACA_AI_NAME} \
        SPRING_DATASOURCE_URL=jdbc:otel:h2:mem:db \
        SPRING_DATASOURCE_DRIVER_CLASS_NAME=io.opentelemetry.instrumentation.jdbc.OpenTelemetryDriver \
    --min-replicas 1 \
    --bind $CONFIG_SERVER

Spring Boot Admin

SBA_SERVER=sbaserver
ROLE_NAME=${UNIQUE_VALUE}role

Create Spring Boot Admin server

az containerapp env java-component admin-for-spring create \
    --environment $ACA_ENV \
    --resource-group $RESOURCE_GROUP_NAME \
    --name $SBA_SERVER

Bind the app to Spring Boot Admin

az containerapp update \
  --name $ACA_PETCLINIC_NAME \
  --resource-group $RESOURCE_GROUP_NAME \
  --bind $SBA_SERVER

View the dashboard

az role definition create --role-definition '{
    "Name": $ROLE_NAME,
    "IsCustom": true,
    "Description": "Can access managed Java Component dashboards in managed environments",
    "Actions": ["Microsoft.App/managedEnvironments/write"],
    "AssignableScopes": ["/subscriptions/<SUBSCRIPTION_ID>"]
}'

export ENVIRONMENT_ID=$(az containerapp env show --name $ACA_ENV --resource-group $RESOURCE_GROUP_NAME --query id -o tsv)
az role assignment create --assignee <USER_OR_SERVICE_PRINCIPAL_ID> --role $ROLE_NAME --scope $ENVIRONMENT_ID
az containerapp env java-component admin-for-spring show --environment $ACA_ENV --resource-group $RESOURCE_GROUP_NAME --name $SBA_SERVER --query properties.ingress.fqdn -o tsv

License

The Spring PetClinic sample application is released under version 2.0 of the Apache License.