Spring Cloud Config Server and client

Creating Config Server

➤ create a new spring boot application with name lab1-server. 
      select spring boot starter project dependencies

• under spring cloud select cloud bootstrap
• under spring cloud config select config server

 make packaging as jar

➤

it automatically add dependency management section to identify spring could parent pom .

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>2.1.8.RELEASE</version>
  <relativePath/> <!-- lookup parent from repository -->
 </parent>
 <groupId>com.demo</groupId>
 <artifactId>lab1-server-2</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <name>lab1-server-2</name>
 <description>spring config server</description>

 <properties>
  <java.version>1.8</java.version>
  <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
 </properties>

 <dependencies>
  <dependency>
   <groupId>org.springframework.cloud</groupId>
   <artifactId>spring-cloud-config-server</artifactId>
  </dependency>
  <dependency>
   <groupId>org.springframework.cloud</groupId>
   <artifactId>spring-cloud-starter</artifactId>
  </dependency>

  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-test</artifactId>
   <scope>test</scope>
  </dependency>
  
  <!-- Spring Team seems to have forgotten about this dependency, needed to run test: -->
  <dependency>
   <groupId>com.jcraft</groupId>
   <artifactId>jsch</artifactId>
  </dependency>
  <!-- Allow for automatic restarts when classpath contents change. -->
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-devtools</artifactId>
         <optional>true</optional>
     </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>

➤in Application class add @EnableConfigServer

@SpringBootApplication

@EnableConfigServer

public class Lab1Server2Application {

public static void main(String[] args) {

SpringApplication.run(Lab1Server2Application.class, args);

}

}

➤Create a new repository on GitHub to hold your application configuration data. Call the repository "ConfigData" . Note the full URI of the repository, you will need this in a following step.

➤Add a new file to your GitHub repository called "lab-3-client.yml” (or lab-3-client.properties). Add a key called "lucky-word" and a value of "Irish", "Rabbit's Foot", "Serendipity", or any other value of your choosing.

➤Back in your project, create an application.yml (or application.properties) file in the root of your classpath (src/main/resources recommended). Add the key "spring.cloud.config.server.git.uri" and the value "https://github.com/"YOUR-GITHUB-ID"/ConfigData", substituting the value for Github ID and repository name as needed.

➤Also within application.yml (or application.properties), set the “server.port” to 8001.

application.yml

---

spring:

  cloud:

    config:

      server:

        git:

          uri: https://github.com/cscdev

          searchPaths: ConfigData

        # "native" is used when the native profile is active, for local tests with a classpath repo:

        native:

          searchLocations: classpath:offline-repository/

server:

  port: 8001

➤Run the application. Open the URL http://localhost:8001/lab-3-client/default/. You should see the JSON result that will actually be used by Spring. 

{

"name": "lab-3-client",

"profiles": ["default"],

"label": null,

"version": "74baf0b6c7a8d55c0dc3635cd13772422489451b",

"state": null,

"propertySources": [{

"name": "https://github.com/cscdev/ConfigData/lab-3-client.yml",

"source": {

"lucky-word": "Irish"

}

}

]

}

Part 2 - Configuring config client

➤Create a new, separate Spring Boot application. 

 select spring boot starter project dependencies

• under spring cloud select cloud bootstrap
• under spring cloud config select config server

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>2.1.8.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.demo</groupId>
<artifactId>lab1-client-2</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>lab1-client-2</name>
<description>spring config server</description>

<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Greenwich.SR3</spring-cloud.version>
</properties>

<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</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-test</artifactId>
<scope>test</scope>
</dependency>

<!-- Allow for automatic restarts when classpath contents change. -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <optional>true</optional>
    </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>

➤Add a bootstrap.yml (or bootstrap.yml) file in the root of your classpath (src/main/resources recommended). Add the following key/values using the appropriate format:

---
spring:
  application:
    name: lab-3-client
  cloud:
    config:
      uri: http://localhost:8001
    
server:
  port: 8002

this file must be "bootstrap" -- not "application" -- so that it is read early in the application startup process

➤Add a REST controller to obtain and display the key

package com.demo;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class MyController {
@Value("${lucky-word}") String luckyWord;

  @GetMapping("/lucky-word")
  public String showLuckyWord() {
    return "The lucky word is: " + luckyWord;
  }
}

➤ go to browser click on below link

http://localhost:8002/lucky-word

you will found

O/P

The lucky word is: Irish