Employees REST API (microservices)

Monorepo REST API built with microservices architecture.

Components

• Gateway
• Discovery server
• Config server
• Employee microservice
• Department microservice

Features

• Microservices architecture
• Spring cloud
• Zipkin support (can be run inside a container)

Architecture

Gateway

The gateway uses the following dependencies:

• Gateway (to route to API)
• Eureka Discovery Client (REST based service to read config)
• Config Client (Read from config server)
• Spring Boot Actuator (Operation and Expose metrics)
• Zipkin

Discovery Server

The discovery server needs:

• Eureka Server (for the discovery server)
• Config Client (for reading from config)
• Spring Boot Actuator

Config Server

The Config server needs the following dependencies

• Config Sever

Employee

The Employee microservice needs the following main dependencies:

• DB driver (MySQL, PostgreSQL, etc)
• Lombok
• Spring Data JPA
• Spring Web
• Config client
• Eureka Discovery Client
• Spring Boot Actuator
• Zipkin
• Spring REST Docs
• Spring Auto REST Docs

Department

The Department microservice needs the following dependencies:

• DB driver (MySQL, PostgreSQL, etc)
• Lombok
• Spring Data JPA
• Spring Web
• Config client
• Eureka Discovery Client
• Spring Boot Actuator
• OpenFeign (added after some coding)
• Zipkin
• Spring REST Docs
• Spring Auto REST Docs

Process of building

1. After creating the gateway, discovery server (Eureka) and config server, add them to the project via File/new/module from existing sources
2. Configure the application.properties or application.yml file.
3. Create and import the employee microservice
4. Config the employee microservice (including JDBC properties to connect to the DB)
   • Create entity inside employee class with the annotations:
     • @Entity (jpa)
     • @Getter (lombok)
     • @Setter (lombok)
     • @AllArgsConstructor (lombok)
     • @NoArgsConstructor (lombok)
     • @Builder (lombok)
     • @Id (jpa)
   • Create repository interface (dao) to extend JPA Repository
   • Create the service (interface and implementation)
   • Create the REST controller for employee
5. Create the department microservice (can use employee as a guide)
6. Establish the HTTP connection between both microservices by using the REST API of Employee in Department
7. Create the client connection in the Department microservice and establish the connection. Can edit the URL so, both microservices communicate using the gateway.
8. Move the config properties to the config server.
9. Use zipkin to track traces between microservices.
   • Use Docker compose yml file to describe the service Zipkin
   • Add the zipkin related dependencies to the microservices:
     • Discovery server
     • Employee
     • Department
   • Execute zipkin after docker desktop.
10. Add the dependencies needed for j-unit 5 and rest docs in microservices with endpoints
    • org.junit.jupiter
    • org.springframework.restdocs
11. Configure the test for each operation
12. Add Dependencies and plugins for spring auto rest docs.
13. Write the test for the full CRUD support