Eureka Registry - Ribbon Load balancer - Application Producer - Application Consumer

Eureka: Expose Service API, it have own Server
Ribbon : load balancer at client side
Histrix : circut breaking, exception hander at application server side

bootstrap.yml:
eureka:
  client:
    registerWithEureka: false
    fetchRegistry: false
  server:
      waitTimeInMsWhenSyncEmpty: 0
  instance:
    hostname: localhost

Eureka 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 http://maven.apache.org/xsd/maven-4.0.0.xsd")
(modelVersion)4.0.0(/modelVersion)

(groupId)com.example(/groupId)
(artifactId)EurekaServer(/artifactId)
(version)0.0.1-SNAPSHOT(/version)
(packaging)jar(/packaging)

(name)EurekaServer(/name)
(description)Demo project for Spring Boot(/description)

(parent)
(groupId)org.springframework.boot(/groupId)
(artifactId)spring-boot-starter-parent(/artifactId)
(version)1.5.6.RELEASE(/version)
(relativePath/) (!-- lookup parent from repository --)
(/parent)

(properties)
(project.build.sourceEncoding)UTF-8(/project.build.sourceEncoding)
(project.reporting.outputEncoding)UTF-8(/project.reporting.outputEncoding)
(java.version)1.8(/java.version)
(/properties)

(dependencies)
(dependency)
(groupId)org.springframework.boot(/groupId)
(artifactId)spring-boot-starter(/artifactId)
(/dependency)

(dependency)
(groupId)org.springframework.cloud(/groupId)
(artifactId)spring-cloud-starter-eureka-server(/artifactId)
(/dependency)
(/dependencies)
(dependencyManagement)
(dependencies)
(dependency)
(groupId)org.springframework.cloud(/groupId)
(artifactId)spring-cloud-dependencies(/artifactId)
(version)Camden.SR6(/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:
server.port=8090

EurekaServerApplication.java
package com.example.demo;

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

@SpringBootApplication
@EnableEurekaServer
public class EurekaServerApplication {

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

========================================================================

Application Producer:
(?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 http://maven.apache.org/xsd/maven-4.0.0.xsd")
(modelVersion)4.0.0(/modelVersion)

(groupId)com.example(/groupId)
(artifactId)EurekaProducer(/artifactId)
(version)0.0.1-SNAPSHOT(/version)
(packaging)jar(/packaging)

(name)EurekaProducer(/name)
(description)Demo project for Spring Boot(/description)

(parent)
(groupId)org.springframework.boot(/groupId)
(artifactId)spring-boot-starter-parent(/artifactId)
(version)1.5.6.RELEASE(/version)
(relativePath/) (!-- lookup parent from repository --)
(/parent)

(properties)
(project.build.sourceEncoding)UTF-8(/project.build.sourceEncoding)
(project.reporting.outputEncoding)UTF-8(/project.reporting.outputEncoding)
(java.version)1.8(/java.version)
(/properties)

(dependencies)
(dependency)
(groupId)org.springframework.boot(/groupId)
(artifactId)spring-boot-starter(/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-eureka(/artifactId)
(/dependency)


(/dependencies)

(dependencyManagement)
(dependencies)
(dependency)
(groupId)org.springframework.cloud(/groupId)
(artifactId)spring-cloud-dependencies(/artifactId)
(version)Camden.SR6(/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:
eureka.client.serviceUrl.defaultZone=http://localhost:8090/eureka
eureka.instance.instanceId=${spring.application.name}:${random.value}

bootstrap.properties:
spring.application.name=employee-producer

Employee.java
package com.javainuse.model;

public class Employee {
private String empId;
private String name;
private String designation;
private double salary;

public Employee() {
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getDesignation() {
return designation;
}

public void setDesignation(String designation) {
this.designation = designation;
}

public double getSalary() {
return salary;
}

public void setSalary(double salary) {
this.salary = salary;
}

public String getEmpId() {
return empId;
}

public void setEmpId(String empId) {
this.empId = empId;
}

}

Controller Class

package com.javainuse.controllers;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RestController;

import com.javainuse.model.Employee;

@RestController

public class TestController {

@RequestMapping(value = "/employee", method = RequestMethod.GET)

public Employee firstPage() {

Employee emp = new Employee();

emp.setName("emp1");

emp.setDesignation("manager");

emp.setEmpId("1");

emp.setSalary(3000);

return emp;

}

}

package com.javainuse;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@SpringBootApplication

@EnableDiscoveryClient

public class SpringBootHelloWorldApplication {

public static void main(String[] args) {

SpringApplication.run(SpringBootHelloWorldApplication.class, args);

}

}

========================================================================

Application Consumer

(?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 http://maven.apache.org/xsd/maven-4.0.0.xsd")

(modelVersion)4.0.0(/modelVersion)

(groupId)com.example(/groupId)

(artifactId)EurekaConsumer(/artifactId)

(version)0.0.1-SNAPSHOT(/version)

(packaging)jar(/packaging)

(name)EurekaConsumer(/name)

(description)Demo project for Spring Boot(/description)

(parent)

(groupId)org.springframework.boot(/groupId)

(artifactId)spring-boot-starter-parent(/artifactId)

(version)1.5.6.RELEASE(/version)

(relativePath/) (!-- lookup parent from repository --)

(/parent)

(properties)

(project.build.sourceEncoding)UTF-8(/project.build.sourceEncoding)

(project.reporting.outputEncoding)UTF-8(/project.reporting.outputEncoding)

(java.version)1.8(/java.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-eureka(/artifactId)

(/dependency)

(dependency)

(groupId)org.springframework.cloud(/groupId)

(artifactId)spring-cloud-starter-ribbon(/artifactId)

(/dependency)

(/dependencies)

(dependencyManagement)

(dependencies)

(dependency)

(groupId)org.springframework.cloud(/groupId)

(artifactId)spring-cloud-dependencies(/artifactId)

(version)Camden.SR6(/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)

package com.javainuse;

import java.io.IOException;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.context.ApplicationContext;

import org.springframework.context.annotation.Bean;

import org.springframework.web.client.RestClientException;

import com.javainuse.controllers.ConsumerControllerClient;

@SpringBootApplication

public class SpringBootHelloWorldApplication {

public static void main(String[] args) throws RestClientException, IOException {

ApplicationContext ctx = SpringApplication.run(

SpringBootHelloWorldApplication.class, args);

ConsumerControllerClient consumerControllerClient=ctx.getBean(ConsumerControllerClient.class);

System.out.println(consumerControllerClient);

consumerControllerClient.getEmployee();

}

@Bean

public  ConsumerControllerClient  consumerControllerClient()

{

return  new ConsumerControllerClient();

}

}

package com.javainuse.controllers;

import java.io.IOException;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.cloud.client.ServiceInstance;

import org.springframework.cloud.client.discovery.DiscoveryClient;

import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;

import org.springframework.http.HttpEntity;

import org.springframework.http.HttpHeaders;

import org.springframework.http.HttpMethod;

import org.springframework.http.MediaType;

import org.springframework.http.ResponseEntity;

import org.springframework.stereotype.Controller;

import org.springframework.web.client.RestClientException;

import org.springframework.web.client.RestTemplate;

@Controller

public class ConsumerControllerClient {

@Autowired

private LoadBalancerClient loadBalancer;

public void getEmployee() throws RestClientException, IOException {

ServiceInstance serviceInstance=loadBalancer.choose("employee-producer");

System.out.println(serviceInstance.getUri());

String baseUrl=serviceInstance.getUri().toString();

baseUrl=baseUrl+"/employee";

RestTemplate restTemplate = new RestTemplate();

ResponseEntity response=null;

try{

response=restTemplate.exchange(baseUrl,

HttpMethod.GET, getHeaders(),String.class);

}catch (Exception ex)

{

System.out.println(ex);

}

System.out.println(response.getBody());

}

private static HttpEntity getHeaders() throws IOException {

HttpHeaders headers = new HttpHeaders();

headers.set("Accept", MediaType.APPLICATION_JSON_VALUE);

return new HttpEntity<>(headers);

}

}

application.properties:
server.port=8091
eureka.client.serviceUrl.defaultZone=http://localhost:8090/eureka

bootstrap.properties:
spring.application.name=employee-consumer