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https://github.com/spring-petclinic/spring-petclinic-cloud

Fork of the Spring Cloud Microservices project packaged to be deployed on several Cloud platforms: Kubernetes and Cloud Foundry
https://github.com/spring-petclinic/spring-petclinic-cloud

cloud-foundry docker kubernetes spring-cloud tanzu wavefront

Last synced: about 1 year ago
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Fork of the Spring Cloud Microservices project packaged to be deployed on several Cloud platforms: Kubernetes and Cloud Foundry

Awesome Lists containing this project

README 

          
# Distributed version of the Spring PetClinic - adapted for Cloud Foundry and Kubernetes 



[![Build Status](https://travis-ci.org/spring-petclinic/spring-petclinic-cloud.svg?branch=master)](https://travis-ci.org/spring-petclinic/spring-petclinic-cloud/) [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)



This microservices branch was initially derived from the [microservices version](https://github.com/spring-petclinic/spring-petclinic-microservices) to demonstrate how to split sample Spring application into [microservices](http://www.martinfowler.com/articles/microservices.html).

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](https://github.com/spring-cloud/spring-cloud-netflix) technology stack. While running on Kubernetes, some components (such as Spring Cloud Config and Eureka Service Discovery) are replaced with Kubernetes-native features such as config maps and Kubernetes DNS resolution.



This fork also demostrates the use of free distributed tracing with Tanzu Observability by Wavefront, which provides cloud-based monitoring of  Spring Boot applications with 5 days of history.



  * [Understanding the Spring Petclinic application](#understanding-the-spring-petclinic-application)

  * [Compiling and pushing to Cloud Foundry:](#compiling-and-pushing-to-cloud-foundry)

  * [Compiling and pushing to Kubernetes](#compiling-and-pushing-to-kubernetes)

    + [Choose your Docker registry](#choose-your-docker-registry)

    + [Setting things up in Kubernetes](#setting-things-up-in-kubernetes)

    + [Settings up databases with helm](#settings-up-databases-with-helm)

    + [Deploying the application](#deploying-the-application)

  * [Starting services locally without Docker](#starting-services-locally-without-docker)

  * [Starting services locally with docker-compose](#starting-services-locally-with-docker-compose)

  * [In case you find a bug/suggested improvement for Spring Petclinic Microservices](#in-case-you-find-a-bug-suggested-improvement-for-spring-petclinic-microservices)

  * [Database configuration](#database-configuration)

    + [Start a MySql database](#start-a-mysql-database)

    + [Use the Spring 'mysql' profile](#use-the-spring--mysql--profile)

  * [Custom metrics monitoring](#custom-metrics-monitoring)

    + [Using Prometheus](#using-prometheus)

    + [Using Grafana with Prometheus](#using-grafana-with-prometheus)

    + [Custom metrics](#custom-metrics)

  * [Looking for something in particular?](#looking-for-something-in-particular-)

  * [Interesting Spring Petclinic forks](#interesting-spring-petclinic-forks)

- [Contributing](#contributing)



## Understanding the Spring Petclinic application



[See the presentation of the Spring Petclinic Framework version](http://fr.slideshare.net/AntoineRey/spring-framework-petclinic-sample-application)



[A blog bost introducing the Spring Petclinic Microsevices](http://javaetmoi.com/2018/10/architecture-microservices-avec-spring-cloud/) (french language)



You can then access petclinic here: http://localhost:8080/



![Spring Petclinic Microservices screenshot](./docs/application-screenshot.png?lastModify=1596391473)



## Compiling and pushing to Cloud Foundry:



The samples below are using Tanzu Application Service (previously Pivotal Cloud Foundry) as the target Cloud Foundry deployment, some adjustments may be needed for other Cloud Foundry distributions.



Please make sure you have the latest `cf` cli installed: https://docs.cloudfoundry.org/cf-cli/install-go-cli.html  

For more information on Tanzu Application Service, see: https://docs.pivotal.io/application-service/2-10/overview/dev.html  

For a list of available Cloud Foundry distributions, see: https://www.cloudfoundry.org/certified-platforms/  

For local testing and development, you can use PCF Dev: https://docs.pivotal.io/pcf-dev/  



This application uses Wavefront as a SaaS that can provide free Spring Boot monitoring and Open Tracing for your application. If you'd like to remove the Wavefront integration, please remove the `wavefront` user-provided service reference from [manifest.yml](./manifest.yml). 



Otherwise, generate a free wavefront token by running one of the apps, for example:



```bash

cd spring-petclinic-api-gateway

mvn spring-boot:run

```



You will see something like this in the logs:



```

A Wavefront account has been provisioned successfully and the API token has been saved to disk.



To share this account, make sure the following is added to your configuration:



	management.metrics.export.wavefront.api-token=2e41f7cf-1111-2222-3333-7397a56113ca

	management.metrics.export.wavefront.uri=https://wavefront.surf



Connect to your Wavefront dashboard using this one-time use link:

https://wavefront.surf/us/AAA4s5f8xJ9yD



```



You free account has now been created.



Create a user-provided service for Wavefront using the data above. For example:



```

cf cups -p '{"uri": "https://wavefront.surf", "api-token": "2e41f7cf-1111-2222-3333-7397a56113ca", "application-name": "spring-petclinic-cloudfoundry", "fremium": "true"}' wavefront

```

If your operator deployed the wavefront proxy in your Cloud Foundry environment, point the URI to the proxy instead. You can obtain the value of the IP and port by creating a service key of the wavefront proxy and viewing the resulting JSON file. 



Contine with creating the services and deploying the application's microservices. A sample is available at `scripts/deployToCloudFoundry.sh`. Note that some of the services' plans may be different in your environment, so please review before executing. For example, you want want to fork the [spring-petclinic-cloud-config](https://github.com/spring-petclinic/spring-petclinic-cloud-config.git) repository if you want to make changes to the configuration.



```

echo "Creating Required Services..."

{

  cf create-service -c '{ "git": { "uri": "https://github.com/spring-petclinic/spring-petclinic-cloud-config.git", "periodic": true }, "count": 3 }' p.config-server standard config &

  cf create-service p.service-registry standard registry & 

  cf create-service p.mysql db-small customers-db &

  cf create-service p.mysql db-small vets-db &

  cf create-service p.mysql db-small visits-db &

  sleep 5

} &> /dev/null

until [ `cf service config | grep -c "succeeded"` -ge 1  ] && [ `cf service registry | grep -c "succeeded"` -ge 1  ] && [ `cf service customers-db | grep -c "succeeded"` -ge 1  ] && [ `cf service vets-db | grep -c "succeeded"` -ge 1  ] && [ `cf service visits-db | grep -c "succeeded"` -ge 1  ]

do

  echo -n "."

done



mvn clean package -Pcloud

cf push --no-start



cf add-network-policy api-gateway --destination-app vets-service --protocol tcp --port 8080

cf add-network-policy api-gateway --destination-app customers-service --protocol tcp --port 8080

cf add-network-policy api-gateway --destination-app visits-service --protocol tcp --port 8080



cf start vets-service & cf start visits-service & cf start customers-service & cf start api-gateway &

```



You can now access your application by querying the route for the `api-gateway`:



```

✗ cf apps

Getting apps in org pet-clinic / space pet-clinic as user@email.com...

OK



name                requested state   instances   memory   disk   urls

api-gateway         started           1/1         1G       1G     api-gateway.apps.mysite.com

customers-service   started           1/1         1G       1G     customers-service.apps.internal

vets-service        started           1/1         1G       1G     vets-service.apps.internal

visits-service      started           1/1         1G       1G     visits-service.apps.internal



```



Access your route (like `api-gateway.apps.mysite.com` above) to see the application.



Access the one-time URL you received when bootstraping Wavefront to see Zipkin traces and other monitoring of your microservices:



![Wavefront dashboard screen](./docs/wavefront-summary.png)



Since we've included `brave.mysql8` in our `pom.xml`, the traces even show the various DB queries traces:



![Wavefront dashboard screen](./docs/wavefront-traces.png)



## Compiling and pushing to Kubernetes



This get a little bit more complicated when deploying to Kubernetes, since we need to manage Docker images, exposing services and more yaml. But we can pull through!



### Choose your Docker registry



You need to define your target Docker registry. Make sure you're already logged in by running `docker login ` or `docker login` if you're just targeting Docker hub.



Setup an env variable to target your Docker registry. If you're targeting Docker hub, simple provide your username, for example:



```bash

export REPOSITORY_PREFIX=odedia

```



For other Docker registries, provide the full URL to your repository, for example:



```bash

export REPOSITORY_PREFIX=harbor.myregistry.com/demo

```



One of the neat features in Spring Boot 2.3 is that it can leverage [Cloud Native Buildpacks](https://buildpacks.io) and [Paketo Buildpacks](https://paketo.io) to build production-ready images for us. Since we also configured the `spring-boot-maven-plugin` to use `layers`, we'll get optimized layering of the various components that build our Spring Boot app for optimal image caching. What this means in practice is that if we simple change a line of code in our app, it would only require us to push the layer containing our code and not the entire uber jar. To build all images and pushing them to your registry, run:



```bash

mvn spring-boot:build-image -Pk8s -DREPOSITORY_PREFIX=${REPOSITORY_PREFIX} && ./scripts/pushImages.sh

```



Since these are standalone microservices, you can also `cd` into any of the project folders and build it indivitually (as well as push it to the registry).



You should now have all your images in your Docker registry. It might be good to make sure you can see them available.



Make sure you're targeting your Kubernetes cluster.



Docker images for kubernetes have been published into DockerHub in the [springcommunity](https://hub.docker.com/u/springcommunity)

organization. You can pull an image:

```

docker pull springcommunity/spring-petclinic-cloud-discovery-service

```



### Setting things up in Kubernetes



Create the `spring-petclinic` namespace for Spring petclinic:



```bash

kubectl apply -f k8s/init-namespace/ 

```



Create a Kubernetes secret to store the URL and API Token of Wavefront (replace values with your own real ones):



```bash

kubectl create secret generic wavefront -n spring-petclinic --from-literal=wavefront-url=https://wavefront.surf --from-literal=wavefront-api-token=2e41f7cf-1111-2222-3333-7397a56113ca

```



Create the Wavefront proxy pod, and the various Kubernetes services that will be used later on by our deployments:



```bash

kubectl apply -f k8s/init-services

```



Verify the services are available:



```bash

✗ kubectl get svc -n spring-petclinic

NAME                TYPE           CLUSTER-IP     EXTERNAL-IP   PORT(S)             AGE

api-gateway         LoadBalancer   10.7.250.24         80:32675/TCP        36s

customers-service   ClusterIP      10.7.245.64            8080/TCP            36s

vets-service        ClusterIP      10.7.245.150           8080/TCP            36s

visits-service      ClusterIP      10.7.251.227           8080/TCP            35s

wavefront-proxy     ClusterIP      10.7.253.85            2878/TCP,9411/TCP   37s

```



Verify the wavefront proxy is running:



```bash

✗ kubectl get pods -n spring-petclinic

NAME                              READY   STATUS    RESTARTS   AGE

wavefront-proxy-dfbd4b695-fdd6t   1/1     Running   0          36s



```



### Settings up databases with helm



We'll now need to deploy our databases. For that, we'll use helm. You'll need helm 3 and above since we're not using Tiller in this deployment.



Make sure you have a single `default` StorageClass in your Kubernetes cluster:



```bash

✗ kubectl get sc

NAME                 PROVISIONER            AGE

standard (default)   kubernetes.io/gce-pd   6h11m



```



Deploy the databases:



```bash

helm repo add bitnami https://charts.bitnami.com/bitnami

helm repo update

helm install vets-db-mysql bitnami/mysql --namespace spring-petclinic --version 8.8.8 --set auth.database=service_instance_db

helm install visits-db-mysql bitnami/mysql --namespace spring-petclinic  --version 8.8.8 --set auth.database=service_instance_db

helm install customers-db-mysql bitnami/mysql --namespace spring-petclinic  --version 8.8.8 --set auth.database=service_instance_db

```



### Deploying the application



Our deployment YAMLs have a placeholder called `REPOSITORY_PREFIX` so we'll be able to deploy the images from any Docker registry. Sadly, Kubernetes doesn't support environment variables in the YAML descriptors. We have a small script to do it for us and run our deployments:



```bash

./scripts/deployToKubernetes.sh

```



Verify the pods are deployed:



```bash

✗ kubectl get pods -n spring-petclinic 

NAME                                 READY   STATUS    RESTARTS   AGE

api-gateway-585fff448f-q45jc         1/1     Running   0          4m20s

customers-db-mysql-0                 1/1     Running   0          11m

customers-service-5d7d686654-kpcmx   1/1     Running   0          4m19s

vets-db-mysql-0                      1/1     Running   0          11m

vets-service-85cb8677df-l5xpj        1/1     Running   0          4m2s

visits-db-mysql-0                    1/1     Running   0          11m

visits-service-654fffbcc7-zj2jw      1/1     Running   0          4m2s

wavefront-proxy-dfbd4b695-fdd6t      1/1     Running   0          14m

```



Get the `EXTERNAL-IP` of the API Gateway:



```bash

✗ kubectl get svc -n spring-petclinic api-gateway 

NAME          TYPE           CLUSTER-IP    EXTERNAL-IP      PORT(S)        AGE

api-gateway   LoadBalancer   10.7.250.24   34.1.2.22   80:32675/TCP   18m

```



You can now browse to that IP in your browser and see the application running.



You should also see monitoring and traces from Wavefront under the application name `spring-petclinic-k8s`:



![Wavefront dashboard screen](./docs/wavefront-k8s.png)



## Starting services locally without Docker



Every microservice is a Spring Boot application and can be started locally using IDE 

or `../mvnw spring-boot:run -Plocal` command.

Remember to enable the `local` Maven profile.



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](https://github.com/openzipkin/zipkin/tree/master/zipkin-server))

* 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`



## Starting services locally with docker-compose



In order to start entire infrastructure using Docker, you have to build images by executing `./mvnw clean install -P buildDocker` 

from a project root. Once images are ready, you can start them with a single command

`docker-compose up`. Containers startup order is coordinated with [`dockerize` script](https://github.com/jwilder/dockerize). 

After starting services it takes a while for API Gateway to be in sync with service registry,

so don't be scared of initial Spring Cloud Gateway timeouts. You can track services availability using Eureka dashboard

available by default at http://localhost:8761.



The `master` branch uses an  Alpine linux  with JRE 8 as Docker base. You will find a Java 11 version in the `release/java11` branch.



*NOTE: Under MacOSX or Windows, make sure that the Docker VM has enough memory to run the microservices. The default settings

are usually not enough and make the `docker-compose up` painfully slow.*



## In case you find a bug/suggested improvement for Spring Petclinic Microservices



Our issue tracker is available here: https://github.com/spring-petclinic/spring-petclinic-cloud/issues



## Database configuration



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.



### Start a MySql database



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/



### Use the Spring 'mysql' profile



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. 



## Custom metrics monitoring



Grafana and Prometheus are included in the `docker-compose.yml` configuration, and the public facing applications

have been instrumented with [MicroMeter](https://micrometer.io) 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](spring-petclinic-api-gateway/src/test/jmeter/petclinic_test_plan.jmx)



![Grafana metrics dashboard](docs/grafana-custom-metrics-dashboard.png)



### Using Prometheus



* Prometheus can be accessed from your local machine at http://localhost:9091



### Using Grafana with Prometheus



* 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](https://grafana.com/dashboards/4701) via the Import Dashboard menu item.

The id for this dashboard is `4701`.



### Custom metrics

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`

* `visits-service` application has the following custom metrics enabled:

  * @Timed: `petclinic.visit`



## Looking for something in particular?



| Spring Cloud components         | Resources  |

|---------------------------------|------------|

| Configuration server            | [Config server properties](spring-petclinic-config-server/src/main/resources/application.yml) and [Configuration repository] |

| Service Discovery               | [Eureka server](spring-petclinic-discovery-server) and [Service discovery client](spring-petclinic-vets-service/src/main/java/org/springframework/samples/petclinic/vets/VetsServiceApplication.java) |

| API Gateway                     | [Spring Cloud Gateway starter](spring-petclinic-api-gateway/pom.xml) and [Routing configuration](/spring-petclinic-api-gateway/src/main/resources/application.yml) |

| Docker Compose                  | [Spring Boot with Docker guide](https://spring.io/guides/gs/spring-boot-docker/) and [docker-compose file](docker-compose.yml) |

| Circuit Breaker                 | [Resilience4j fallback method](spring-petclinic-api-gateway/src/main/java/org/springframework/samples/petclinic/api/boundary/web/ApiGatewayController.java)  |

| Grafana / Prometheus Monitoring | [Micrometer implementation](https://micrometer.io/), [Spring Boot Actuator Production Ready Metrics] |



 Front-end module  | Files |

|-------------------|-------|

| Node and NPM      | [The frontend-maven-plugin plugin downloads/installs Node and NPM locally then runs Bower and Gulp](spring-petclinic-ui/pom.xml)  |

| Bower             | [JavaScript libraries are defined by the manifest file bower.json](spring-petclinic-ui/bower.json)  |

| Gulp              | [Tasks automated by Gulp: minify CSS and JS, generate CSS from LESS, copy other static resources](spring-petclinic-ui/gulpfile.js)  |

| Angular JS        | [app.js, controllers and templates](spring-petclinic-ui/src/scripts/)  |



## Interesting Spring Petclinic forks



The Spring Petclinic master branch in the main [spring-projects](https://github.com/spring-projects/spring-petclinic)

GitHub org is the "canonical" implementation, currently based on Spring Boot and Thymeleaf.



This [spring-petclinic-cloud](https://github.com/spring-petclinic/spring-petclinic-cloud/) project is one of the [several forks](https://spring-petclinic.github.io/docs/forks.html) 

hosted in a special GitHub org: [spring-petclinic](https://github.com/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.



# Contributing



The [issue tracker](https://github.com/spring-petclinic/spring-petclinic-microservices/issues) is the preferred channel for bug reports, features requests and submitting pull requests.



For pull requests, editor preferences are available in the [editor config](.editorconfig) for easy use in common text editors. Read more and download plugins at .



[Configuration repository]: https://github.com/spring-petclinic/spring-petclinic-microservices-config

[Spring Boot Actuator Production Ready Metrics]: https://docs.spring.io/spring-boot/docs/current/reference/html/production-ready-metrics.html