Microservice Architecture with Multiple Languages

The idea for this project is to show a case for applying Microservice Architecture using multiple languages.

Most all services are built in Java with Spring Boot 2 + Webflux + MongoDB but there are other services using NodeJS, Kotlin and Python.

The web application is using React and also a beta version using JHipster.

Feel free to create a new microservice using a different language(Go?, Ruby?, C#?), just please following the minimal requirements:

Create a new folder on root and put your code
Add a minimal documentation
Add a Rest API
Add JWT Validation
Add Tests
Add Dockerfile
Add MongoDB or some other NoSql
Add Eureka Client(if possible)
Add Spring Cloud Config Client(if possible)

PS: A better approach would be a microservice per repository but for simplicity all microservices are in the same repo.

If you want to contribute please check TODO List.

Inspired by the book Microservices Patterns(Chris Richardson - @crichardson).

Microservice Patterns
Prerequisites
Microservice Diagram
Installing all services using Docker Compose
Docker Commands
Monitoring - Spring Boot Admin
Service Discovery - Eureka
Externalized Configuration - Spring Config
Prometheus and Grafana
Zipkin Request Tracing
Manual Installation - NOT RECOMMENDED
Accessing React Web App
List of default users
Kubernetes - Google Cloud Platform
~~Travis CI/CD~~
Github Actions CI/CD
TODO List
References
Postman Collection

Microservice Patterns

The following list of Microservice Patterns was applied so far.

Server-side service discovery - Used Spring Cloud Eureka Server on eureka-server project.
Client-side service discovery - Used Spring Cloud Eureka Client for all java microservices(admin-server, user-service, person-service, etc).
API Gateway - Used Spring Cloud Zuul on edge-server project.
Externalized configuration - Used Spring Cloud Config Server on config-server service. Yml files are in config-server/configuration.
Exception Tracking - Used Spring Boot Admin on admin-server project.
Access token - Used Spring Oauth2 with JWT on authentication-service project and client services(user-service, person-service, nodejs-service, kotin-service, etc) expect a valid JWT Token.
Health Check API - Used Spring Boot Actuator Starter For Java microservices and express-actuator for NodeJS.
Distributed tracing - Used Zipkin for viewing log traces and Spring Cloud Sleuth for Java microservices.
Application metrics - Used Spring Micrometer Prometheus for Java microservices and express-prom-bundle for NodeJS.
Database per service - Used MongoDB instance per service.
Shared database - Used Redis for sharing sessions for services that require login.

PS: Used <artifactId>eureka-consul-adapter</artifactId> on eureka-server for scraping data for Prometheus

To know more about each pattern look at Microservice Architecture

Prerequisites

JDK 1.8
Maven 3
Docker 17.05.0-ce+ - Not necessary but recommended otherwise the services should run by command
Docker Compose 1.23.2 - Not necessary but recommended otherwise the services should run by command

Microservice Diagram

Installing All Services using Docker Compose

The easiest way to run all microservices is using docker-compose, run the following commands:

On root folder first need to generate the docker images.

# at once for building the docker images
mvn clean install docker:build

Then on docker folder run all microservices using

docker-compose up -d

PS: Whenever change is made on the source code it is necessary to rebuild the image, you can use the following command:

docker-compose up --build week-menu-api react-webapp

Docker Commands

To see logs for a specific docker container:

docker logs -f SERVICE_NAME

PS: Service names are on docker-compose.yml -> container_name

To execute a command inside the container:

docker exec -it week-menu-api sh

To stop and remove all containers:

docker-compose down -v

To restart/start/stop/remove specific container:

docker-compose restart SERVICE_NAME
docker-compose up SERVICE_NAME
docker-compose stop SERVICE_NAME
docker-compose rm SERVICE_NAME

Monitoring - Spring Boot Admin

To see information(environment, instances, logs, etc) related to all microservices registered with Eureka use Spring Boot Admin - http://localhost:9000.

PS: Need login with a valid user and role ADMIN. See at Default Users

Service Discovery - Eureka

To see all microservices registered with Eureka use http://localhost:8761.

PS: Need login with a valid user and role ADMIN. See at Default Users

Externalized Configuration - Spring Cloud Config

To see configuration related to specific service use Spring Config http://localhost:8888/${SERVICE_NAME}/${SPRING_PROFILE}.

PS: Need login with a valid user and role ADMIN. See at Default Users

Prometheus and Grafana

Prometheus is a tool for generating metrics from the requests.

Grafana is a tool for communicate with Prometheus and display the data with dashboards.

Spring Boot 2 by default uses Micrometer for monitoring JVM/Microservices Applications.

To access Prometheus UI

To access Grafana Dashboard.

PS: It depends on docker.

Sleuth and Zipkin

Sleuth is used for creating a unique identifier(Span) and set to a request for all microservices calls.

Zipkin is used for request tracing through microservices.

To access Zipkin UI.

Manual Installation - NOT RECOMMENDED

If for some reason you cannot install docker/docker-compose you can run all services manually.

On root folder run the following command at once:

mvn clean install

Run Spring Boot

To run the services use the following command in each Microservices folders:

mvn spring-boot:run -Dspring-boot.run.arguments="--server.port={PORT}"

eureka-server - PORT=8761
config-server - PORT=8888
edge-server - PORT=9006
admin-server - PORT=9000
authentication-service - PORT=9999
person-service - PORT=8082
user-service - PORT=8083

PS: To login at Eureka/Config/Edge/Admin need a user with role ADMIN. See at Default Users

Run Node.js service

On nodejs-service folder run the following commands:

sudo npm install

sudo npm start

Run React Web app

On react-webapp folder run the following commands:

sudo npm install

sudo npm start

Accessing React App

To access React Web App.

Default Users

Following the list of default users:

[email protected]/password - ROLE_ADMIN

[email protected]/password123 - ROLE_PERSON_CREATE, ROLE_PERSON_READ, ROLE_PERSON_SAVE

[email protected]/test - ROLE_PERSON_READ

Kubernetes - Google Cloud Platform

The code is deployed at Google Cloud Platform, to access it go through https://spendingbetter.com.

Following useful commands for kubernetes

Installation

#helm create ingress - RBAC enabled
kubectl create serviceaccount --namespace kube-system tiller
kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller
helm init --service-account tiller
helm list
helm init --tiller-tls-verify
helm init
kubectl get deployments -n kube-system
helm install --name nginx-ingress stable/nginx-ingress --set rbac.create=true --set controller.publishService.enabled=true

#helm list
helm list

#create tls
kubectl create secret tls ingress-tls --cert /etc/sslmate/www.spendingbetter.com.chained.crt --key /etc/sslmate/www.spendingbetter.com.key

#create generic certs
kubectl create secret generic spendingbetter-p12 --from-file=/etc/sslmate/www.spendingbetter.com.p12
kubectl create secret generic spendingbetter-crt --from-file=/etc/sslmate/www.spendingbetter.com.crt

#list certs
kubectl get secrets

#list specific cert
kubectl describe secret ingress-tls

#show ingress
kubectl get ing
kubectl describe ingress


# Istio
# Get Grafana Configuration
kubectl get service grafana --namespace istio-system -o yaml

# Update Grafana Configuration
kubectl edit service grafana --namespace istio-system

Deployment

cd kubernetes

#create docker image
docker tag eureka-server:latest eu.gcr.io/spring-boot-gke-243520/eureka-server:4.0
docker tag docker_react-webapp:latest eu.gcr.io/spring-boot-gke-243520/react-webapp:6.0

#push docker image
docker push eu.gcr.io/spring-boot-gke-243520/eureka-server:4.0
docker push eu.gcr.io/spring-boot-gke-243520/react-webapp:6.0

#Deploy
kubectl apply -f deployment-admin-server.yml

#Undeploy
kubectl delete -f deployment-admin-server.yml

#see logs
kubectl logs admin-server-XXXXX -f

#exec command
kubectl exec -it redis-5b4699dd74-qckm9 -- sh

#show all pods
kubectl get pods --show-labels

#create config map
kubectl create configmap prometheus --from-file=../docker/prometheus-prod.yml

kubectl create configmap grafana-dashboard --from-file=../docker/create-datasource-and-dashboard.sh

kubectl create configmap grafana-datasource --from-file=../docker/grafana-datasource.yaml

#port forward
kubectl port-forward $(kubectl get pod --selector="app=eureka-server" --output jsonpath='{.items[0].metadata.name}') 8761:8761

#delete specific ingress
kubectl delete ingress ingress-gateway-forward-https

#cpu usage
kubectl get nodes --show-labels
kubectl describe nodes gke-your-first-cluster
kubectl top nodes

Enable Ingress

Example Ingress Configuration

Install Helm

Kubernetes + Zuul

Example Spring Boot 2 + Kubernetes + Zuul

Secure Discovery Example