入門案例
1、創建Maven聚合項目
- Feign-Demo:父項目
- eureka-server:Eureka註冊中心
- eureka-server02:Eureka註冊中心
- service-provider:服務提供者
- service-consumer:服務消費者
父項目: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>cn.yanghuisen</groupId>
<artifactId>Feign-Demo</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>eureka-server</module>
<module>service-provider</module>
<module>service-consumer</module>
</modules>
<!-- 繼承 spring-boot-starter-parent 依賴 -->
<!-- 使用繼承方式,實現複用,符合繼承的都可以被使用 -->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.0.RELEASE</version>
</parent>
<!--
集中定義依賴組件版本號,但不引入,
在子工程中用到聲明的依賴時,可以不加依賴的版本號,
這樣可以統一管理工程中用到的依賴版本
-->
<properties>
<!-- Spring Cloud Hoxton.SR5 依賴 -->
<spring-cloud.version>Hoxton.SR5</spring-cloud.version>
</properties>
<!-- 項目依賴管理 父項目只是聲明依賴,子項目需要寫明需要的依賴(可以省略版本信息) -->
<dependencyManagement>
<dependencies>
<!-- spring cloud 依賴 -->
<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>
</project>
2、eureka註冊中心
2.1、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">
<parent>
<artifactId>Feign-Demo</artifactId>
<groupId>cn.yanghuisen</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka-server</artifactId>
<name>eureka-server</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<!-- 項目依賴 -->
<dependencies>
<!-- netflix eureka server 依賴 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
<!-- spring boot web 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- spring boot test 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</project>
application.yml
server:
port: 8761 # 端口
spring:
application:
name: eureka-server # 應用名稱(集羣下相同)
# 配置 Eureka Server 註冊中心
eureka:
instance:
hostname: eureka01 # 主機名,不配置的時候將根據操作系統的主機名來獲取
prefer-ip-address: true # 是否使用 ip 地址註冊
instance-id: ${spring.cloud.client.ip-address}:${server.port} # ip:port
client:
# 設置服務註冊中心地址,指向另一個註冊中心
service-url: # 註冊中心對外暴露的註冊地址
defaultZone: http://localhost:8762/eureka/
啓動類
package cn.yanghuisen;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@SpringBootApplication
// 開啓 EurekaServer 註解
@EnableEurekaServer
public class EurekaServerApplication {
public static void main(String[] args) {
SpringApplication.run(EurekaServerApplication.class, args);
}
}
2.2、eureka-server02
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">
<parent>
<artifactId>Feign-Demo</artifactId>
<groupId>cn.yanghuisen</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka-server02</artifactId>
<name>eureka-server02</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<!-- 項目依賴 -->
<dependencies>
<!-- netflix eureka server 依賴 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
<!-- spring boot web 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- spring boot test 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</project>
application.yml
spring:
application:
name: eureka-server # 應用名稱(集羣下相同)
# 端口
server:
port: 8762
# 配置 Eureka Server 註冊中心
eureka:
instance:
hostname: eureka02 # 主機名,不配置的時候將根據操作系統的主機名來獲取
prefer-ip-address: true # 是否使用 ip 地址註冊
instance-id: ${spring.cloud.client.ip-address}:${server.port} # ip:port
client:
# 設置服務註冊中心地址,指向另一個註冊中心
service-url: # 註冊中心對外暴露的註冊地址
defaultZone: http://localhost:8761/eureka/
啓動類
package cn.yanghuisen;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@SpringBootApplication
// 開啓 EurekaServer 註解
@EnableEurekaServer
public class EurekaServer02Application {
public static void main(String[] args) {
SpringApplication.run(EurekaServer02Application.class, args);
}
}
3、provider服務提供者
3.1、service-provider
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">
<parent>
<artifactId>Feign-Demo</artifactId>
<groupId>cn.yanghuisen</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>service-provider</artifactId>
<name>service-provider</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<!-- 項目依賴 -->
<dependencies>
<!-- netflix eureka client 依賴 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<!-- spring boot web 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- lombok 依賴 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<scope>provided</scope>
</dependency>
<!-- spring boot test 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</project>
實體類
package cn.yanghuisen.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Product implements Serializable {
private Integer id;
private String productName;
private Integer productNum;
private Double productPrice;
}
服務類接口
package cn.yanghuisen.service;
import cn.yanghuisen.pojo.Product;
import java.util.List;
/**
* 商品服務
*/
public interface ProductService {
/**
* 查詢商品列表
*
* @return
*/
List<Product> selectProductList();
}
服務類接口實現類
package cn.yanghuisen.service.impl;
import cn.yanghuisen.pojo.Product;
import cn.yanghuisen.service.ProductService;
import org.springframework.stereotype.Service;
import java.util.Arrays;
import java.util.List;
/**
* 商品服務
*/
@Service
public class ProductServiceImpl implements ProductService {
/**
* 查詢商品列表
*
* @return
*/
@Override
public List<Product> selectProductList() {
return Arrays.asList(
new Product(1, "華爲手機", 1, 5800D),
new Product(2, "聯想筆記本", 1, 6888D),
new Product(3, "小米平板", 5, 2020D)
);
}
}
控制層
package cn.yanghuisen.controller;
import cn.yanghuisen.pojo.Product;
import cn.yanghuisen.service.ProductService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
@RequestMapping("/product")
public class ProductController {
@Autowired
private ProductService productService;
/**
* 查詢商品列表
*
* @return
*/
@GetMapping("/list")
public List<Product> selectProductList() {
return productService.selectProductList();
}
}
啓動類
package cn.yanghuisen;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
// 開啓 EurekaClient 註解,目前版本如果配置了 Eureka 註冊中心,默認會開啓該註解
//@EnableEurekaClient
public class ServiceProviderApplication {
public static void main(String[] args) {
SpringApplication.run(ServiceProviderApplication.class, args);
}
}
3.2、service-provider02
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">
<parent>
<artifactId>Feign-Demo</artifactId>
<groupId>cn.yanghuisen</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>service-provider02</artifactId>
<name>service-provider02</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<!-- 項目依賴 -->
<dependencies>
<!-- netflix eureka client 依賴 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<!-- spring boot web 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- lombok 依賴 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<scope>provided</scope>
</dependency>
<!-- spring boot test 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</project>
實體類
package cn.yanghuisen.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Product implements Serializable {
private Integer id;
private String productName;
private Integer productNum;
private Double productPrice;
}
服務類接口
package cn.yanghuisen.service;
import cn.yanghuisen.pojo.Product;
import java.util.List;
/**
* 商品服務
*/
public interface ProductService {
/**
* 查詢商品列表
*
* @return
*/
List<Product> selectProductList();
}
服務類接口實現類
package cn.yanghuisen.service.impl;
import cn.yanghuisen.pojo.Product;
import cn.yanghuisen.service.ProductService;
import org.springframework.stereotype.Service;
import java.util.Arrays;
import java.util.List;
/**
* 商品服務
*/
@Service
public class ProductServiceImpl implements ProductService {
/**
* 查詢商品列表
*
* @return
*/
@Override
public List<Product> selectProductList() {
return Arrays.asList(
new Product(1, "華爲手機", 1, 5800D),
new Product(2, "聯想筆記本", 1, 6888D),
new Product(3, "小米平板", 5, 2020D)
);
}
}
控制層
package cn.yanghuisen.controller;
import cn.yanghuisen.pojo.Product;
import cn.yanghuisen.service.ProductService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
@RestController
@RequestMapping("/product")
public class ProductController {
@Autowired
private ProductService productService;
/**
* 查詢商品列表
*
* @return
*/
@GetMapping("/list")
public List<Product> selectProductList() {
return productService.selectProductList();
}
}
啓動類
package cn.yanghuisen;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
// 開啓 EurekaClient 註解,目前版本如果配置了 Eureka 註冊中心,默認會開啓該註解
//@EnableEurekaClient
public class ServiceProviderApplication {
public static void main(String[] args) {
SpringApplication.run(ServiceProviderApplication.class, args);
}
}
4、consumer服務消費者
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">
<parent>
<artifactId>Feign-Demo</artifactId>
<groupId>cn.yanghuisen</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>service-consumer</artifactId>
<name>service-consumer</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<!-- 項目依賴 -->
<dependencies>
<!-- netflix eureka client 依賴 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<!--去除jackson-dataformat-xml,否則會返回xml文件,而不是JSON-->
<exclusions>
<exclusion>
<groupId>com.fasterxml.jackson.dataformat</groupId>
<artifactId>jackson-dataformat-xml</artifactId>
</exclusion>
</exclusions>
</dependency>
<!-- spring cloud openfeign 依賴 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<!-- spring boot web 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- lombok 依賴 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<scope>provided</scope>
</dependency>
<!-- spring boot test 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</project>
eureka中默認集成com.fasterxml.jackson.dataformat
,用於返回xml格式的數據,但是由於xml的等級比JSON高,所以在要返回JSON的時候,將會被替換爲XML,剔除com.fasterxml.jackson.dataformat
後就可以正常返回JSON數據。
application.yml
server:
port: 9090 # 端口
spring:
application:
name: service-consumer # 應用名稱
# 配置 Eureka Server 註冊中心
eureka:
client:
register-with-eureka: false # 是否將自己註冊到註冊中心,默認爲 true
registry-fetch-interval-seconds: 10 # 表示 Eureka Client 間隔多久去服務器拉取註冊信息,默認爲 30 秒
service-url: # 設置服務註冊中心地址
defaultZone: http://localhost:8761/eureka/,http://localhost:8762/eureka/
實體類
package cn.yanghuisen.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Product implements Serializable {
private Integer id;
private String productName;
private Integer productNum;
private Double productPrice;
}
package cn.yanghuisen.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
import java.util.List;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Order implements Serializable {
private Integer id;
private String orderNo;
private String orderAddress;
private Double totalPrice;
private List<Product> productList;
}
服務類接口
package cn.yanghuisen.service;
import cn.yanghuisen.pojo.Product;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import java.util.List;
// 聲明需要調用的服務
@FeignClient("service-provider")
public interface ProductService {
/**
* 查詢商品列表
*
* @return
*/
// 配置需要調用的服務地址及參數
@GetMapping("/product/list")
List<Product> selectProductList();
}
package cn.yanghuisen.service;
import cn.yanghuisen.pojo.Order;
public interface OrderService {
/**
* 根據主鍵查詢訂單
*
* @param id
* @return
*/
Order selectOrderById(Integer id);
}
服務接口實現類
package cn.yanghuisen.service.impl;
import cn.yanghuisen.pojo.Order;
import cn.yanghuisen.service.OrderService;
import cn.yanghuisen.service.ProductService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class OrderServiceImpl implements OrderService {
@Autowired
private ProductService productService;
/**
* 根據主鍵查詢訂單
*
* @param id
* @return
*/
@Override
public Order selectOrderById(Integer id) {
return new Order(id, "order-001", "中國", 22788D,
productService.selectProductList());
}
}
控制層
package cn.yanghuisen.controller;
import cn.yanghuisen.pojo.Order;
import cn.yanghuisen.service.OrderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@RequestMapping("/order")
public class OrderController {
@Autowired
private OrderService orderService;
/**
* 根據主鍵查詢訂單
*
* @param id
* @return
*/
@GetMapping("/{id}")
public Order selectOrderById(@PathVariable("id") Integer id) {
return orderService.selectOrderById(id);
}
}
啓動類
package cn.yanghuisen;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.openfeign.EnableFeignClients;
@SpringBootApplication
// 開啓 EurekaClient 註解,目前版本如果配置了 Eureka 註冊中心,默認會開啓該註解
//@EnableEurekaClient
// 開啓 FeignClients 註解
@EnableFeignClients
public class ServiceConsumerApplication {
public static void main(String[] args) {
SpringApplication.run(ServiceConsumerApplication.class, args);
}
}
啓動項目,先啓動兩個註冊中心,再啓動兩個服務提供者,最後啓動服務消費者
訪問:http://localhost:9090/order/1
負載均衡
1、全局
@Bean
public RandomRule randomRule() {
return new RandomRule();
}
2、局部
# 負載均衡策略
# service-provider 爲調用的服務的名稱
service-provider:
ribbon:
NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule