This microservices branch was initially derived from AngularJS version to demonstrate how to split sample Spring application into microservices. To achieve that goal we use Spring Cloud Gateway, Spring Cloud Circuit Breaker, Spring Cloud Config, Spring Cloud Sleuth, Resilience4j, Micrometer and the Eureka Service Discovery from the Spring Cloud Netflix technology stack.
Every microservice is a Spring Boot application and can be started locally using IDE (Lombok plugin has to be set up) or ../mvnw spring-boot:run
command. Please note that supporting services (Config and Discovery Server) must be started before any other application (Customers, Vets, Visits and API).
Startup of Tracing server, Admin server, Grafana and Prometheus is optional.
If everything goes well, you can access the following services at given location:
- Discovery Server - http://localhost:8761
- Config Server - http://localhost:8888
- AngularJS frontend (API Gateway) - http://localhost:8080
- Customers, Vets and Visits Services - random port, check Eureka Dashboard
- Tracing Server (Zipkin) - http://localhost:9411/zipkin/ (we use openzipkin)
- Admin Server (Spring Boot Admin) - http://localhost:9090
- Grafana Dashboards - http://localhost:3000
- Prometheus - http://localhost:9091
You can tell Config Server to use your local Git repository by using native
Spring profile and setting
GIT_REPO
environment variable, for example:
-Dspring.profiles.active=native -DGIT_REPO=/projects/spring-petclinic-microservices-config
This will setup a Kubernetes IN Docker cluster named petclinic by default.
First, install Kind.
next we will create the Petclinic Kind cluster. Run make kind-test-cluster
to create the petclinic
Kubernetes cluster.
This will also setup helm and a kubeconfig, the kubeconfig location can be found using the following command kind get kubeconfig-path --name=petclinic
assuming you're using the default KIND_PROFILE
.
You can verify your new cluster information by running: KUBECONFIG=$(kind get kubeconfig-path --name=petclinic) kubectl cluster-info
Enter kubectl get pods
and press enter. You should see that you have no resources currently, but otherwise see no errors.
See the presentation of the Spring Petclinic Framework version
A blog bost introducing the Spring Petclinic Microsevices (french language)
You can then access petclinic here: http://localhost:8080/
Architecture diagram of the Spring Petclinic Microservices
Our issue tracker is available here: https://github.com/spring-petclinic/spring-petclinic-microservices/issues
In its default configuration, Petclinic uses an in-memory database (HSQLDB) which gets populated at startup with data.
A similar setup is provided for MySql in case a persistent database configuration is needed.
Dependency for Connector/J, the MySQL JDBC driver is already included in the pom.xml
files.
You may start a MySql database with docker:
docker run -e MYSQL_ROOT_PASSWORD=petclinic -e MYSQL_DATABASE=petclinic -p 3306:3306 mysql:5.7.8
or download and install the MySQL database (e.g., MySQL Community Server 5.7 GA), which can be found here: https://dev.mysql.com/downloads/
To use a MySQL database, you have to start 3 microservices (visits-service
, customers-service
and vets-services
)
with the mysql
Spring profile. Add the --spring.profiles.active=mysql
as programm argument.
By default, at startup, database schema will be created and data will be populated.
You may also manually create the PetClinic database and data by executing the "db/mysql/{schema,data}.sql"
scripts of each 3 microservices.
In the application.yml
of the [Configuration repository], set the initialization-mode
to never
.
If you are running the microservices with Docker, you have to add the mysql
profile into the (Dockerfile)[docker/Dockerfile]:
ENV SPRING_PROFILES_ACTIVE docker,mysql
In the mysql section
of the application.yml
from the [Configuration repository], you have to change
the host and port of your MySQL JDBC connection string.
Grafana and Prometheus are included in the docker-compose.yml
configuration, and the public facing applications
have been instrumented with MicroMeter to collect JVM and custom business metrics.
A JMeter load testing script is available to stress the application and generate metrics: petclinic_test_plan.jmx
- Prometheus can be accessed from your local machine at http://localhost:9091
- An anonymous access and a Prometheus datasource are setup.
- A
Spring Petclinic Metrics
Dashboard is available at the URL http://localhost:3000/d/69JXeR0iw/spring-petclinic-metrics. You will find the JSON configuration file here: docker/grafana/dashboards/grafana-petclinic-dashboard.json. - You may create your own dashboard or import the Micrometer/SpringBoot dashboard via the Import Dashboard menu item.
The id for this dashboard is
4701
.
Spring Boot registers a lot number of core metrics: JVM, CPU, Tomcat, Logback...
The Spring Boot auto-configuration enables the instrumentation of requests handled by Spring MVC.
All those three REST controllers OwnerResource
, PetResource
and VisitResource
have been instrumented by the @Timed
Micrometer annotation at class level.
customers-service
application has the following custom metrics enabled:- @Timed:
petclinic.owner
- @Timed:
petclinic.pet
- @Timed:
visits-service
application has the following custom metrics enabled:- @Timed:
petclinic.visit
- @Timed:
Spring Cloud components | Resources |
---|---|
API Gateway | Spring Cloud Gateway starter and Routing configuration |
Circuit Breaker | Resilience4j fallback method |
Grafana / Prometheus Monitoring | Micrometer implementation, Spring Boot Actuator Production Ready Metrics |
The Spring Petclinic main
branch in the main spring-projects
GitHub org is the "canonical" implementation, currently based on Spring Boot and Thymeleaf.
This spring-petclinic-cloud project is one of the several forks hosted in a special GitHub org: spring-petclinic. If you have a special interest in a different technology stack that could be used to implement the Pet Clinic then please join the community there.
The issue tracker is the preferred channel for bug reports, features requests and submitting pull requests.
For pull requests, editor preferences are available in the editor config for easy use in common text editors. Read more and download plugins at http://editorconfig.org.