Spring Cloud Starter Eureka Server Jar Download: Best Practices and Tips
Spring Cloud Starter Eureka Server Jar Download
If you are developing microservices with Spring Boot and Spring Cloud, you might have heard of Spring Cloud Netflix Eureka. It is a service discovery solution that allows you to register and discover your microservices without hard-coding their locations. In this article, we will show you how to download and install the spring-cloud-starter-eureka-server jar file, which is the dependency you need to set up a Eureka Server in your project. We will also show you how to register and discover services with Eureka Server, and how to access and monitor its dashboard.
Spring Cloud Netflix Eureka is a part of the Spring Cloud Netflix project, which provides integrations with Netflix OSS (Open Source Software) components. Eureka is one of these components, and it is responsible for service discovery.
spring-cloud-starter-eureka-server jar download
Service discovery is a key feature in a microservices architecture, where you have multiple independent services that need to communicate with each other. Instead of hard-coding the hostnames and ports of these services, you can use a service registry, where each service can register itself with its location and metadata. Then, other services can query the registry to find and consume the registered services.
Eureka Server is the service registry component that you can set up in your project. It has the following features and benefits:
It is easy to use and configure with Spring Boot and Spring Cloud annotations and properties.
It supports both client-side and server-side load balancing, which means that each client can cache the registry information locally and use a load-balancing algorithm to choose the best service instance.
It is resilient to failures, as it can handle network errors, service outages, and registry replication issues.
It provides a web interface where you can view the registered services and their instances, as well as their health and status.
It integrates well with other Spring Cloud Netflix components, such as Zuul (a routing and filtering proxy), Hystrix (a circuit breaker and fallback mechanism), Ribbon (a client-side load balancer), and Feign (a declarative REST client).
How to Download and Install Eureka Server Jar
To set up a Eureka Server in your project, you need to download and install the spring-cloud-starter-eureka-server jar file, which is the dependency that contains all the required libraries and configurations. Here are the steps you need to follow:
Prerequisites and Dependencies
To use Eureka Server, you need to have the following prerequisites:
Java 8 or later
Maven or Gradle as your build tool
Spring Boot 2.x as your application frameworkTo use Eureka Server, you also need to add the following dependency to your pom.xml file if you are using Maven, or to your build.gradle file if you are using Gradle:
spring-cloud-starter-eureka-server maven dependency
spring-cloud-starter-eureka-server gradle dependency
spring-cloud-starter-eureka-server enable self preservation
spring-cloud-starter-eureka-server peer awareness
spring-cloud-starter-eureka-server health check
spring-cloud-starter-eureka-server load balancing
spring-cloud-starter-eureka-server retry mechanism
spring-cloud-starter-eureka-server fallback strategy
spring-cloud-starter-eureka-server circuit breaker
spring-cloud-starter-eureka-server cache refresh interval
spring-cloud-starter-eureka-server heartbeat interval
spring-cloud-starter-eureka-server registration interval
spring-cloud-starter-eureka-server eviction interval
spring-cloud-starter-eureka-server lease duration
spring-cloud-starter-eureka-server lease renewal interval
spring-cloud-starter-eureka-server lease expiration duration ratio
spring-cloud-starter-eureka-server prefer ip address over hostname
spring-cloud-starter-eureka-server prefer same zone eureka servers
spring-cloud-starter-eureka-server use dns for fetching service urls
spring-cloud-starter-eureka-server service url zone mapping
spring-cloud-starter-eureka-server default zone
spring-cloud-starter-eureka-server client region
spring-cloud-starter-eureka-server client filter only up instances
spring-cloud-starter-eureka-server client fetch registry
spring-cloud-starter-eureka-server client register with eureka
``` ```gradle implementation 'org.springframework.cloud:spring-cloud-starter-eureka-server:3.0.4' ``` You can find the latest version of the dependency on the .
A convenient way to generate a project template with the Eureka Server dependency is to use , which is a web-based tool that allows you to create and configure Spring Boot applications. You can follow these steps to use Spring Initializr:
Go to the and fill in the basic information, such as the project name, group ID, artifact ID, packaging, and Java version.
Select Spring Boot 2.x as the Spring Boot version.
Under the dependencies section, search for and select Eureka Server.
Click on the Generate button to download a zip file containing the project template.
Extract the zip file and open the project in your preferred IDE (Integrated Development Environment).
Eureka Server Configuration
After you have created and opened the project, you need to enable and configure Eureka Server in your Spring Boot application. You can do this by following these steps:
In the main class of your application, add the @EnableEurekaServer annotation above the class declaration. This annotation tells Spring Boot that this application is a Eureka Server and should start as one.
```java 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); ``` In the application.properties file (or application.yml if you prefer YAML format), add some properties to configure Eureka Server. For example, you can set the server port, the application name, and whether to register itself with other Eureka Servers (if you have more than one). Here is an example of some basic properties:
```properties server.port=8761 spring.application.name=eureka-server eureka.client.register-with-eureka=false eureka.client.fetch-registry=false ``` You can find more properties and their descriptions on the .
Save and run your application. You should see some logs indicating that Eureka Server is up and running on port 8761.
How to Register and Discover Services with Eureka Server
Now that you have set up a Eureka Server in your project, you can use it to register and discover your microservices. To do this, you need to add the Eureka Client dependency to your microservice applications, and configure them to register with and query from Eureka Server. Here are the steps you need to follow:
Eureka Client Dependency and Annotation
To use Eureka Client in your microservice applications, you need to add the following dependency to your pom.xml file if you are using Maven, or to your build.gradle file if you are using Gradle:
``` ```gradle implementation 'org.springframework.cloud:spring-cloud-starter-eureka-client:3.0.4' ``` You can find the latest version of the dependency on the .
In addition, you need to add the @EnableEurekaClient annotation above the main class of your microservice application. This annotation tells Spring Boot that this application is a Eureka Client and should communicate with Eureka Server.
```java import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.netflix.eureka.EnableEurekaClient; @SpringBootApplicat