springCloud学习四之通过Eureka实现服务调用

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原创最新推荐文章于 2026-08-06 14:13:28 发布 915 阅读 AI 写同款· GEO 优化 ›

sprinCloud学习之使用Eureka实现服务注册与调用一、配置Eureka-Server，作为服务的注册中心 1、新建一个maven工程，在pom文件中引入相关依赖 <dependency> <groupId>org.springframework.cloud</groupId>  <... 阅读详情

1.实现Eureke Server

查看：https://blog.youkuaiyun.com/codingToMaster/article/details/119082910

2.创建服务提供方

依赖：

POM配置：

<?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>2.5.3</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.learn.eureka-provider1</groupId>
	<artifactId>Eureka-provider1</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>Eureka-provider1</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>11</java.version>
		<spring-cloud.version>2020.0.3</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-netflix-eureka-client</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>

配置文件：

server.port=6060
spring.application.name=Provider1
#设置服务注册中心的URL，用于client和server端交流,这里是客户端，寻找主机
eureka.client.service-url.defaultZone=http://euk1.com:8081/eureka/

实现一个Controller:

package com.learn.eurekaprovider1.controller;

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

@RestController
public class MainController {

    @GetMapping("/getHi")
    public String getHi() {
        return "Hello";
    }
}

http://localhost:6060/getHi

查看eureka服务器：

Rest服务调用

官方文档

https://github.com/Netflix/eureka/wiki/Eureka-REST-operations

Operation	HTTP action	Description
Register new application instance	POST /eureka/v2/apps/appID	Input: JSON/XMLpayload HTTPCode: 204 on success
De-register application instance	DELETE /eureka/v2/apps/appID/instanceID	HTTP Code: 200 on success
Send application instance heartbeat	PUT /eureka/v2/apps/appID/instanceID	HTTP Code: * 200 on success * 404 if instanceIDdoesn’t exist
Query for all instances	GET /eureka/v2/apps	HTTP Code: 200 on success Output: JSON/XML
Query for all appID instances	GET /eureka/v2/apps/appID	HTTP Code: 200 on success Output: JSON/XML
Query for a specific appID/instanceID	GET /eureka/v2/apps/appID/instanceID	HTTP Code: 200 on success Output: JSON/XML
Query for a specific instanceID	GET /eureka/v2/instances/instanceID	HTTP Code: 200 on success Output: JSON/XML
Take instance out of service	PUT /eureka/v2/apps/appID/instanceID/status?value=OUT_OF_SERVICE	HTTP Code: * 200 on success * 500 on failure
Move instance back into service (remove override)	DELETE /eureka/v2/apps/appID/instanceID/status?value=UP (The value=UP is optional, it is used as a suggestion for the fallback status due to removal of the override)	HTTP Code: * 200 on success * 500 on failure
Update metadata	PUT /eureka/v2/apps/appID/instanceID/metadata?key=value	HTTP Code: * 200 on success * 500 on failure
Query for all instances under a particular vip address	GET /eureka/v2/vips/vipAddress	* HTTP Code: 200 on success Output: JSON/XML * 404 if the vipAddressdoes not exist.
Query for all instances under a particular secure vip address	GET /eureka/v2/svips/svipAddress	* HTTP Code: 200 on success Output: JSON/XML * 404 if the svipAddressdoes not exist.

查询所有的服务：

http://localhost:8081/eureka/apps

或者某个服务：

http://localhost:8081/eureka/instances/DESKTOP-GRIPBVL:Provider1:6060

http://localhost:8081/eureka/apps/PROVIDER1

服务状态

http://localhost:8081/eureka/status

如果需要json格式可以加个请求头Accept:application/json

{
    "generalStats": {
        "environment": "test",
        "num-of-cpus": "16",
        "total-avail-memory": "517mb",
        "current-memory-usage": "45mb (8%)",
        "server-uptime": "00:03"
    },
    "applicationStats": {
        "registered-replicas": "",
        "available-replicas": "",
        "unavailable-replicas": ""
    },
    "instanceInfo": {
        "instanceId": "localhost",
        "hostName": "localhost",
        "app": "UNKNOWN",
        "ipAddr": "192.168.29.1",
        "status": "UP",
        "overriddenStatus": "UNKNOWN",
        "port": {
            "$": 8080,
            "@enabled": "true"
        },
        "securePort": {
            "$": 443,
            "@enabled": "false"
        },
        "countryId": 1,
        "dataCenterInfo": {
            "@class": "com.netflix.appinfo.InstanceInfo$DefaultDataCenterInfo",
            "name": "MyOwn"
        },
        "leaseInfo": {
            "renewalIntervalInSecs": 30,
            "durationInSecs": 90,
            "registrationTimestamp": 0,
            "lastRenewalTimestamp": 0,
            "evictionTimestamp": 0,
            "serviceUpTimestamp": 0
        },
        "metadata": {
            "management.port": "8080",
            "jmx.port": "7649"
        },
        "homePageUrl": "http://localhost:8080/",
        "statusPageUrl": "http://localhost:8080/actuator/info",
        "healthCheckUrl": "http://localhost:8080/actuator/health",
        "vipAddress": "unknown",
        "secureVipAddress": "unknown",
        "isCoordinatingDiscoveryServer": "false",
        "lastUpdatedTimestamp": "1586328420409",
        "lastDirtyTimestamp": "1586328420519"
    }

注册到eureka的服务信息查看

get: {ip:port}/eureka/apps

注册到eureka的具体的服务查看

get: {ip:port}/eureka/apps/{appname}/{id}

服务续约

put：{ip:port}/eureka/apps/{appname}/{id}?lastDirtyTimestamp={}&status=up

更改服务状态

put：{ip:port}/eureka/apps/{appname}/{id}/status?lastDirtyTimestamp={}&value={UP/DOWN} 对应eureka源码的：InstanceResource.statusUpdate

删除状态更新

delete：{ip:port}/eureka/apps/{appname}/{id}/status?lastDirtyTimestamp={}&value={UP/DOWN}

删除服务

delete: {ip:port}/eureka/apps/{appname}/{id}

元数据

Eureka的元数据有两种：标准元数据和自定义元数据。标准元数据：主机名、IP地址、端口号、状态页和健康检查等信息，这些信息都会被发布在服务注册表中，用于服务之间的调用。

自定义元数据：可以使用eureka.instance.metadata-map配置，这些元数据可以在远程客户端中访问，但是一般不改变客户端行为，除非客户端知道该元数据的含义。

可以在配置文件中对当前服务设置自定义元数据，可后期用户个性化使用

元数据可以配置在eureka服务器和eureka的客户端上

eureka.instance.metadata-map.daniu=dalao

服务消费方：

POM依赖

<?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>2.5.3</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.learn</groupId>
	<artifactId>eureka-consumer1</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>eureka-consumer1</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>11</java.version>
		<spring-cloud.version>2020.0.3</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-netflix-eureka-client</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>

配置文件：

server.port=3030
spring.application.name=Consumer1
#设置服务注册中心的URL，用于client和server端交流,这里是客户端，寻找主机
eureka.client.service-url.defaultZone=http://euk1.com:8081/eureka/

启动类：

package com.learn.eurekaconsumer1;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class EurekaConsumer1Application {

	public static void main(String[] args) {
		SpringApplication.run(EurekaConsumer1Application.class, args);
	}

}

controller:

package com.learn.eurekaconsumer1.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import java.util.List;

@RestController
public class MainController {

    @Autowired
    DiscoveryClient client;

    @GetMapping("/client")
    public String getProvider() {
        List<ServiceInstance> instances = client.getInstances("Provider1");
        ServiceInstance serviceInstance = instances.get(0);
        System.out.println(serviceInstance);
        String url = "http://" + serviceInstance.getHost() + ":" + serviceInstance.getPort() + "/getHi";
        System.out.println(url);
        RestTemplate restTemplate = new RestTemplate();
        String queryResult = restTemplate.getForObject(url, String.class);
        return queryResult;
    }
}