Demo for a typical Modern App Architecture with Spring Cloud

Presentation slides

Deployment

Docker Compose

Build container images with Cloud Native Buildpacks and start containers.

./mvnw spring-boot:build-image
docker compose up

Set environment variables in different terminal session for API usage.

GATEWAY_URL="http://0.0.0.0:$(docker compose port gateway 8080 | awk -F ':' '{print $2}')"
ACCESS_TOKEN=$(curl --location "http://0.0.0.0:$(docker compose port auth-server 9000 | awk -F ':' '{print $2}')/oauth2/token" \
--header 'Content-Type: application/x-www-form-urlencoded' \
--header "Authorization: Basic $(echo -n "default-client-id:default-client-secret" | base64)" \
--data-urlencode 'grant_type=client_credentials' \
--data-urlencode 'scope=openid profile' | jq -r .access_token)

To stop the containers, press CTRL+C to interrupt the process and run docker compose down.

API usage

• Fetch products:

  curl $GATEWAY_URL/services/product-service/api/v1/products --header "Authorization: Bearer $ACCESS_TOKEN"
  

• Fetch orders:

  curl $GATEWAY_URL/services/order-service/api/v1/orders --header "Authorization: Bearer $ACCESS_TOKEN"
  

• Create order (After 10 seconds the status of the order should be DELIVERED)

  curl -XPOST "$GATEWAY_URL/services/order-service/api/v1/orders" --header "Authorization: Bearer $ACCESS_TOKEN" --header "Content-Type: application/json" --data '{"productId":1,"shippingAddress":"Stuttgart"}'
  

• Update externalized application configuration Fork the repository and adjust the spring.cloud.config.server.git.uri configuration in config-server/src/main/resources/application.yaml. Change the product-service.product-names configuration property in externalized-configuration/product-service.yaml and run the following command to refresh the bean with the new configuration.

  curl -XPOST $GATEWAY_URL/services/product-service/actuator/refresh --header "Authorization: Bearer $ACCESS_TOKEN"
  

• Call custom actuator endpoint to clear caches

  curl -XPOST "$GATEWAY_URL/services/order-service/actuator/cache" --header "Authorization: Bearer $ACCESS_TOKEN"