关于SpringCloud的中的Eureka使用方法

首先创建一个空项目：

创建父工程shop_parent 在IDEA中创建父工程 shop_parent 并引入坐标 ：

  org.springframework.boot
  spring-boot-starter-parent
  2.3.9.RELEASE

  
    org.springframework.boot
    spring-boot-starter-web
  
  
    org.springframework.boot
    spring-boot-starter-logging
  
  
    org.springframework.boot
    spring-boot-starter-test
    test
  
  
    org.projectlombok
    lombok
    1.18.4
    provided
  



  
    
      org.springframework.cloud
      spring-cloud-dependencies
      Hoxton.SR10
      pom
      import
    
  

继续创建微服务模块也就是子模块：product_service 、order_service

搭建maven项目：

    
        org.springframework.boot
        spring-boot-starter-web
    
    
        mysql
        mysql-connector-java
        8.0.28
    
    
        com.baomidou
        mybatis-plus-boot-starter
        3.4.2
    
    
    
        org.springframework.cloud
        spring-cloud-starter-netflix-eureka-client
    

要注意一定要指向父模块：没有的需要自己配置

 实现代码中的实体类：

@Data
public class Product {
    private Long id;
    private String productName;
    private Integer status;
    private BigDecimal price;
    private String productDesc;
    private String caption;
    private Integer inventory;
}

编写dao：采用的是SpringBoot和MybatisPlus

public interface ProductMapper extends BaseMapper {
}

编写service：

public interface ProductService extends IService {
}

@Service
public class ProductServiceImpl extends ServiceImpl implements ProductService {
}

编写web：

@RestController
@RequestMapping("/product")
public class ProductController {
    @Autowired
    private ProductService productService;
    @GetMapping("/{id}")
    public Product findById(@PathVariable Long id){
        Product product = productService.getById(id);
        return product;
    }
}

创建配置类：application.yml

server:
  port: 9010 #端口
spring:
  application:
    name: productservice #服务名称
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/shop?useUnicode=true&characterEncoding=utf8
    username: root
    password: root
#mp日志
mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
  global-config:
    db-config: #设置表名前缀
      table-prefix: tb_
      id-type: assign_uuid
#配置Eureka
eureka:
  client:
    service-url:
      defaultZone: http://localhost:9000/eureka

 创建启动类：

@SpringBootApplication
@MapperScan("com.dao") // 指定扫描的 Mapper 接口所在的包
public class ProductApp {
    public static void main( String[] args ) {
        SpringApplication.run(ProductApp.class);
    }

    @Bean
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }
}

搭建order与上一个模块一样不一一叙述了：

@Data
public class Order {
    private Long id;
    private Long userId;
    private Long productId;
    private Long number;
    private String productName;
    private String username;
    private BigDecimal price;
    private BigDecimal amount;
}

public interface OrderMapper extends BaseMapper {

}

public interface OrderService extends IService {
}

@Service
public class OrderServiceImpl extends ServiceImpl implements OrderService {

}

@RestController
@RequestMapping("/order")
public class OrderController {
    @Autowired
    private OrderService orderService;

    @Autowired
    private RestTemplate restTemplate;

    @GetMapping("/{id}")
    public Product findById(@PathVariable Long id){
        Product product = restTemplate.getForObject("http://productservice/product/1", Product.class);
//Order order = orderService.getById(id);
        return product;
//        Order order = orderService.getById(id);
//        return order;
    }
}

server:
  port: 9020 #端口
spring:
  application:
    name: orderservice #服务名称
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/shop?useUnicode=true&characterEncoding=utf8
    username: root
    password: root
#mp日志
mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
  global-config:
    db-config: #设置表名前缀
      table-prefix: tb_
      id-type: assign_uuid
eureka:
  client:
    service-url:
      defaultZone: http://127.0.0.1:9000/eureka/

@SpringBootApplication
@MapperScan("com.dao") // 指定扫描的 Mapper 接口所在的包
public class SpringOrderApp{
    public static void main( String[] args ) {
        SpringApplication.run(SpringOrderApp.class);
    }

    @Bean
    @LoadBalanced
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }
}

 通过RestTemplate调用微服务：

@Bean
@LoadBalanced
public RestTemplate restTemplate(){
    return new RestTemplate();
}

@Autowired

private RestTemplate restTemplate ;

@GetMapping ( "/{id}" )

public Product findById ( @PathVariable Long id ){

Product product =

restTemplate . getForObject ( "http://localhost:9010/product/1" , Product . class );

//Order order = orderService.getById(id);

return product ;

}

IDEA 开启并配置 services 窗口 ：

搭建Eureka注册中心：

创建 eureka_server 子模块：

同上

引入maven坐标：

  
    org.springframework.cloud
    spring-cloud-starter-netflix-eureka-server
  

配置application.yml：

server:
  port: 9000
spring:
  application:
    name: eurekaserver #eureka的服务名称
eureka:
  client:
    service-url: #eureka的地址信息
      defaultZone: http://127.0.0.1:9000/eureka

配置启动类：

@SpringBootApplication
@EnableEurekaServer //激活Eureka Server端配置
public class EurekaServerApp
{
    public static void main( String[] args )
    {
        SpringApplication.run(EurekaServerApp.class);
    }
}

启动两个实例：

-Dserver.port=9011

服务拉取 ： String url = "http://productservice/product/" + id ;

在order-service项目的启动类中的RestTemplate添加负载均衡注解：

@Bean

@LoadBalanced

public RestTemplate restTemplate (){

return new RestTemplate ();

} }

负载均衡策略修改 ：

在启动类加上新的规则

@Bean

public IRule randomRule (){

return new RandomRule ();

}

在服务消费者【service-order】的application.yml配置文件中修改负载均衡策略：

## 需要调用的微服务名称

productservice :

ribbon :

NFLoadBalancerRuleClassName : com.netflix.loadbalancer.RandomRule

最后附上数据库：

/*

 Navicat Premium Data Transfer

 Source Server         : localhost_3306

 Source Server Type    : MySQL

 Source Server Version : 80023

 Source Host           : localhost:3306

 Source Schema         : security

 Target Server Type    : MySQL

 Target Server Version : 80023

 File Encoding         : 65001

 Date: 07/01/2024 09:49:45

*/

SET NAMES utf8mb4;

SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------

-- Table structure for tb_permission

-- ----------------------------

DROP TABLE IF EXISTS `tb_permission`;

CREATE TABLE `tb_permission`  (

  `id` int NOT NULL AUTO_INCREMENT,

  `name` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '权限名称',

  `url` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '请求地址',

  `parent_id` int NULL DEFAULT NULL COMMENT '父权限主键',

  `type` varchar(24) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '权限类型，M-菜单。A-子菜单，U-普通请求',

  `permit` varchar(128) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '权限字符串描述，如user:list 用户查看权限',

  `remark` text CHARACTER SET utf8 COLLATE utf8_general_ci NULL COMMENT '描述',

  PRIMARY KEY (`id`) USING BTREE

) ENGINE = InnoDB AUTO_INCREMENT = 13 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of tb_permission

-- ----------------------------

INSERT INTO `tb_permission` VALUES (1, '登录', '/login', 0, 'U', 'login:login', '登录权限');

INSERT INTO `tb_permission` VALUES (2, '进入登录页面', '/login', 0, 'U', 'login:tologin', '进入登录权限');

INSERT INTO `tb_permission` VALUES (3, '退出', '/logout', 0, 'U', 'logout', '退出权限');

INSERT INTO `tb_permission` VALUES (4, '注册', '/register', 0, 'U', 'reg:register', '注册权限');

INSERT INTO `tb_permission` VALUES (5, '进入注册页面', '/toRegister', 0, 'U', 'reg:toregister', '进入注册权限');

INSERT INTO `tb_permission` VALUES (6, '用户管理', '', 0, 'M', '用户:经理', '用户管理权限');

INSERT INTO `tb_permission` VALUES (7, '用户查询', '/user/list', 6, 'A', 'user:list', '用户查询权限');

INSERT INTO `tb_permission` VALUES (8, '用户新增', '/user/add', 6, 'U', 'user:add', '用户新增权限');

INSERT INTO `tb_permission` VALUES (9, '进入用户新增页面', '/user/toAdd', 6, 'U', 'user:toAdd', '进入用户新增页面权限');

INSERT INTO `tb_permission` VALUES (10, '用户修改', '/user/modify', 6, 'U', 'user:modify', '用户修改权限');

INSERT INTO `tb_permission` VALUES (11, '进入用户修改页面', '/user/tomodify', 6, 'U', 'user:toModify', '进入用户修改页面权限');

INSERT INTO `tb_permission` VALUES (12, '用户删除', '/user/remove', 6, 'U', 'user:remove', '用户删除权限');

-- ----------------------------

-- Table structure for tb_role

-- ----------------------------

DROP TABLE IF EXISTS `tb_role`;

CREATE TABLE `tb_role`  (

  `id` int NOT NULL AUTO_INCREMENT,

  `name` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '角色名称',

  `remark` text CHARACTER SET utf8 COLLATE utf8_general_ci NULL COMMENT '角色描述',

  PRIMARY KEY (`id`) USING BTREE

) ENGINE = InnoDB AUTO_INCREMENT = 3 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of tb_role

-- ----------------------------

INSERT INTO `tb_role` VALUES (1, '超级管理员', '全部权限');

INSERT INTO `tb_role` VALUES (2, '普通用户', '基础权限');

-- ----------------------------

-- Table structure for tb_role_permission

-- ----------------------------

DROP TABLE IF EXISTS `tb_role_permission`;

CREATE TABLE `tb_role_permission`  (

  `role_id` int NULL DEFAULT NULL COMMENT '角色ID',

  `permission_id` int NULL DEFAULT NULL COMMENT '权限ID'

) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of tb_role_permission

-- ----------------------------

INSERT INTO `tb_role_permission` VALUES (1, 1);

INSERT INTO `tb_role_permission` VALUES (1, 2);

INSERT INTO `tb_role_permission` VALUES (1, 3);

INSERT INTO `tb_role_permission` VALUES (1, 4);

INSERT INTO `tb_role_permission` VALUES (1, 5);

INSERT INTO `tb_role_permission` VALUES (1, 6);

INSERT INTO `tb_role_permission` VALUES (1, 7);

INSERT INTO `tb_role_permission` VALUES (1, 8);

INSERT INTO `tb_role_permission` VALUES (1, 9);

INSERT INTO `tb_role_permission` VALUES (1, 10);

INSERT INTO `tb_role_permission` VALUES (1, 11);

INSERT INTO `tb_role_permission` VALUES (1, 12);

INSERT INTO `tb_role_permission` VALUES (1, 13);

INSERT INTO `tb_role_permission` VALUES (2, 1);

INSERT INTO `tb_role_permission` VALUES (2, 2);

INSERT INTO `tb_role_permission` VALUES (2, 3);

INSERT INTO `tb_role_permission` VALUES (2, 4);

INSERT INTO `tb_role_permission` VALUES (2, 5);

INSERT INTO `tb_role_permission` VALUES (2, 6);

-- ----------------------------

-- Table structure for tb_user

-- ----------------------------

DROP TABLE IF EXISTS `tb_user`;

CREATE TABLE `tb_user`  (

  `id` int NOT NULL AUTO_INCREMENT,

  `name` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '姓名',

  `username` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户名',

  `password` varchar(128) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '密码',

  `remark` text CHARACTER SET utf8 COLLATE utf8_general_ci NULL COMMENT '描述',

  PRIMARY KEY (`id`) USING BTREE

) ENGINE = InnoDB AUTO_INCREMENT = 3 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of tb_user

-- ----------------------------

INSERT INTO `tb_user` VALUES (1, '超级管理员', 'admin', '123', '超级管理员');

INSERT INTO `tb_user` VALUES (2, '普通用户', 'guest', 'guest', '普通用户');

-- ----------------------------

-- Table structure for tb_user_role

-- ----------------------------

DROP TABLE IF EXISTS `tb_user_role`;

CREATE TABLE `tb_user_role`  (

  `user_id` int NULL DEFAULT NULL COMMENT '用户ID',

  `role_id` int NULL DEFAULT NULL COMMENT '角色ID'

) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of tb_user_role

-- ----------------------------

INSERT INTO `tb_user_role` VALUES (1, 1);

INSERT INTO `tb_user_role` VALUES (2, 2);

SET FOREIGN_KEY_CHECKS = 1;