Cloud-Eureka服务治理-Ribbon负载均衡

构建Cloud父工程

父工程只做依赖版本管理不引入依赖

pom.xml

 <packaging>pom</packaging>


    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.9.RELEASE</version>
        <relativePath/>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR10</spring-cloud.version>
        <mysql.version>5.1.47</mysql.version>
        <mybatis.version>2.1.1</mybatis.version>
        <junit.version>4.12</junit.version>
        <log4j.version>1.2.17</log4j.version>
        <lombok.version>1.16.18</lombok.version>

    </properties>

    <dependencyManagement>
        <dependencies>
            <!-- springCloud -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <!-- mysql驱动 -->
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>${mysql.version}</version>
            </dependency>
            <!--mybatis-->
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>${mybatis.version}</version>
            </dependency>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit.version}</version>
            </dependency>
            <dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>${log4j.version}</version>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok.version}</version>
                <optional>true</optional>
            </dependency>
        </dependencies>

    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
    </dependencies>

构建用户模块

CREATE TABLE `tb_user` (
`id` bigint NOT NULL AUTO_INCREMENT,
`username` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '收件人',
`address` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '地址',
PRIMARY KEY (`id`) USING BTREE,
UNIQUE KEY `username` (`username`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=109 DEFAULT CHARSET=utf8mb3 ROW_FORMAT=COMPACT;

INSERT INTO `tb_user`(`id`, `username`, `address`) VALUES (1, '柳岩', '湖南省衡阳市');
INSERT INTO `tb_user`(`id`, `username`, `address`) VALUES (2, '文二狗', '陕西省西安市');
INSERT INTO `tb_user`(`id`, `username`, `address`) VALUES (3, '华沉鱼', '湖北省十堰市');
INSERT INTO `tb_user`(`id`, `username`, `address`) VALUES (4, '张必沉', '天津市');
INSERT INTO `tb_user`(`id`, `username`, `address`) VALUES (5, '郑爽爽', '辽宁省沈阳市大东区');
INSERT INTO `tb_user`(`id`, `username`, `address`) VALUES (6, '范兵兵', '山东省青岛市');

pom.xml

 <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
    </dependencies>
    <build>
        <finalName>app</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

application.yml

server:
  port: 8081
spring:
  application:
    name: user-service
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/cloud-user?useSSL=false&useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&serverTimezone=GMT%2B8&useCursorFetch=true
    username: root
    password: 123456
  #redis:
    #port: 6379
    #database: 0
      #password: 1111111111111
      #ssl: false
      ###################################################
      ##redis 集群环境配置
      #cluster:
      #  nodes: 127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003
      #  commandTimeout: 5000
mybatis:
  type-aliases-package: com.example.userservice.pojo
  configuration:
    map-underscore-to-camel-case: true
logging:
  level:
    com.example.userservice.mapper: debug

pojo

@Data
public class User {
    private Long id;
    private String username;
    private String address;
}

mapper

public interface UserMapper {
    
    @Select("select * from tb_user where id = #{id}")
    User findById(@Param("id") Long id);
}

service

public interface UserService {
    User queryById(Long id);
}

impl

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapper userMapper;

    public User queryById(Long id) {
        return userMapper.findById(id);
    }
}

controller

@RestController
@RequestMapping("/user")
@Slf4j
public class UserController {

    @Autowired
    private UserService userService;

    @Value("${server.port}")
    private String serverPort;

    @GetMapping("/serverport")
    public String serverport(){
        return serverPort;
    }


    @GetMapping("/{id}")
    public User queryById(@PathVariable("id") Long id) {
        return userService.queryById(id);
    }
}

这样你可以开多个

构建订单模块

CREATE TABLE `tb_order` (
`id` bigint NOT NULL AUTO_INCREMENT COMMENT '订单id',
`user_id` bigint NOT NULL COMMENT '用户id',
`name` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '商品名称',
`price` bigint NOT NULL COMMENT '商品价格',
`num` int DEFAULT '0' COMMENT '商品数量',
PRIMARY KEY (`id`) USING BTREE,
UNIQUE KEY `username` (`name`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=109 DEFAULT CHARSET=utf8mb3 ROW_FORMAT=COMPACT;

INSERT INTO `tb_order` VALUES (101, 1, 'Apple 苹果 iPhone 12 ', 699900, 1);
INSERT INTO `tb_order` VALUES (102, 2, '雅迪 yadea 新国标电动车', 209900, 1);
INSERT INTO `tb_order` VALUES (103, 3, '骆驼（CAMEL）休闲运动鞋女', 43900, 1);
INSERT INTO `tb_order` VALUES (104, 4, '小米10 双模5G 骁龙865', 359900, 1);
INSERT INTO `tb_order` VALUES (105, 5, 'OPPO Reno3 Pro 双模5G 视频双防抖', 299900, 1);
INSERT INTO `tb_order` VALUES (106, 6, '美的（Midea) 新能效冷静星II ', 544900, 1);
INSERT INTO `tb_order` VALUES (107, 2, '西昊/SIHOO 人体工学电脑椅子', 79900, 1);
INSERT INTO `tb_order` VALUES (108, 3, '梵班（FAMDBANN）休闲男鞋', 31900, 1);

pom.xml

 <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
 <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
    </dependencies>
    <build>
        <finalName>orderserver</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

pojo

@Data
public class Order {
    private Long id;
    private Long price;
    private String name;
    private Integer num;
    private Long userId;
    private User user;
}

@Data
public class User {
    private Long id;
    private String username;
    private String address;
}

mapper

public interface OrderMapper {

    @Select("select * from tb_order where id = #{id}")
    Order findById(Long id);
}

service

public interface OrderService {
    Order queryOrderById(Long orderId);
}

impl

@Service
public class OrderServiceImpl implements OrderService {

    @Autowired
    private OrderMapper orderMapper;


    @Override
    public Order queryOrderById(Long orderId) {
        return orderMapper.findById(orderId);
    }
}

controller

@RestController
@RequestMapping("/order")
public class OrderController {


    @Autowired
    private OrderService orderService;

    @GetMapping("{orderId}")
    public Order queryOrderByUserId(@PathVariable("orderId") Long orderId) {
        // 根据id查询订单并返回
        return orderService.queryOrderById(orderId);
    }
}

合并公共代码

像pojo可以放在common-api里

构建基础公用模块

使用RestTemplate进行服务间调用

服务调用出现的问题

通过硬编码的方式调用,那么当服务多了又该如何应对

搭建单机Eureka服务

服务既可以是生产者,也可是是消费者也可以同时扮演生产者和消费者两个角色

Eureka分服务端和客户端

我们要注册进去的OrderServer和UserServer都是客户端

所有注册到Eureka的服务每30秒都会给注册中心发送心跳检测,证明我活着

server:
  port: 7001
spring:
  application:
    name: eureka-server
eureka:
  instance:
    hostname: eurekaserver  # eureka服务端的实例名称  集群的时候配置
  client:
    # 表示不向注册中心注册自己  集群必须为true
    register-with-eureka: true
    # 表示自己就是注册中心，职责是维护服务实例，并不需要去检索服务  单
    fetch-registry: true
    service-url:
      # 设置与eureka server交互的地址查询服务和注册服务都需要依赖这个地址  ${}是上面定义的
      defaultZone: http://127.0.0.1:${server.port}/eureka/