Spring Boot Microservices — Part2— config-server and RefreshScope

Please starting this tutorial, please go through: https://prateek-ashtikar512.medium.com/spring-boot-microservices-part1-eureka-discivery-service-48d6e00258a

In this tutorial, I will setup the config-server and will help you to fetch the configurations from the github. This way we can avoid having an applications details into application itself, we can have a one place where we can store all these details and fetch as when needed.

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
>
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.7</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>config-server</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>config-server</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>11</java.version>
<spring-cloud.version>2021.0.2</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-config-server</artifactId>
</dependency>

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

</project>

application.properties

spring.application.name=configuration-server
server.port
=8888
spring.cloud.config.server.git.uri
=https://github.com/javaHelper/microservices-config-server
spring.cloud.config.server.git.username
=
spring.cloud.config.server.git.password=
spring.cloud.config.server.git.clone-on-start=true
spring.cloud.config.server.git.default-label
=master

ConfigServerApplication.java

package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.config.server.EnableConfigServer;

@SpringBootApplication
@EnableConfigServer
public class ConfigServerApplication {

public static void main(String[] args) {
SpringApplication.run(ConfigServerApplication.class, args);
}
}

GET — http://localhost:8888/order-service/default

{
"name": "order-service",
"profiles": [
"default"
],
"label": null,
"version": "4d75497e9a9983bb237e66996676637e3cfe3522",
"state": null,
"propertySources": [
{
"name": "https://github.com/javaHelper/microservices-config-server/order-service.properties",
"source": {
"spring.datasource.url": "jdbc:mysql://localhost:3306/order-service",
"spring.datasource.driver-class-name": "com.mysql.cj.jdbc.Driver",
"spring.jpa.properties.hibernate.dialect": "org.hibernate.dialect.MySQL8Dialect",
"spring.jpa.hibernate.ddl-auto": "update",
"spring.datasource.initialization-mode": "always",
"spring.jpa.show-sql": "true"
}
}
]
}

GET — http://localhost:8888/product-service/default

{
"name": "product-service",
"profiles": [
"default"
],
"label": null,
"version": "4d75497e9a9983bb237e66996676637e3cfe3522",
"state": null,
"propertySources": [
{
"name": "https://github.com/javaHelper/microservices-config-server/product-service.properties",
"source": {
"test.name": "Spring Developer"
}
}
]
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
>
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.7</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</description>

<properties>
<java.version>11</java.version>
<spring-cloud.version>2021.0.2</spring-cloud.version>
</properties>

<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>

<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>

</project>

application.properties

spring.application.name=product-service
server.port
=0
eureka.instance.instance-id
=${spring.application.name}:${random.uuid}

#https://docs.spring.io/spring-cloud-config/docs/current/reference/html/
spring.config.import=optional:configserver:http://localhost:8888?fail-fast=true&max-attempts=10&max-interval=1500
management.endpoints.web.exposure.include
=*

TestController.java

package com.example.controller;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api/test")
@RefreshScope
public class TestController {

@Value("${test.name}")
private String name;

@GetMapping
public String test() {
return name;
}
}

No changes in ProductController, ProductRepository and Product model class.

ProductController.java

package com.example.controller;

import com.example.model.Product;
import com.example.repository.ProductRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/api/product")
@RequiredArgsConstructor
public class ProductController {
private final ProductRepository productRepository;

@GetMapping
@ResponseStatus(HttpStatus.OK)
public List<Product> findAll() {
return productRepository.findAll();
}

@PostMapping
@ResponseStatus(HttpStatus.CREATED)
public void createProduct(@RequestBody Product product) {
productRepository.save(product);
}
}

Product.java

package com.example.model;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;

import java.math.BigDecimal;

@AllArgsConstructor
@NoArgsConstructor
@Data
@Builder
@Document(value = "product")
public class Product {
@Id
private String id;
private String name;
private String description;
private BigDecimal price;
}

ProductRepository.java

package com.example.repository;

import com.example.model.Product;
import org.springframework.data.mongodb.repository.MongoRepository;

public interface ProductRepository extends MongoRepository<Product, String> {
}

ProductServiceApplication.java

package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

@SpringBootApplication
@EnableEurekaClient
public class ProductServiceApplication {

public static void main(String[] args) {
SpringApplication.run(ProductServiceApplication.class, args);
}
}

As you can see application started on Port 55862 port!

Currently value stored in git repository is —

Now, go ahead and change the value of test.name in github , now without restarting the config-server, you can read the value!

Now make the POST request to dynamically load the configurations.

As you can see above latest value coming from the github in the above Screen shot.

order-service

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
>
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.7</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>order-service</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>order-service</name>
<description>Demo project for Spring Boot</description>

<properties>
<java.version>11</java.version>
<spring-cloud.version>2021.0.2</spring-cloud.version>
</properties>


<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>

<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>

</project>

application.properties

#MySQL DB
spring.datasource.username=root
spring.datasource.password
=password

spring.application.name
=order-service
server.port
=0
eureka.instance.instance-id
=${spring.application.name}:${random.uuid}
spring.config.import
=optional:configserver:http://localhost:8888?fail-fast=true&max-attempts=10&max-interval=1500

management.endpoints.web.exposure.include
=*

And the other details will remain unchanged.

--

--

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store