简单Spring cloud微服务项目搭建

IDE开发工具：IntelliJ IDEA 14.0.2

版本管理：Maven

技术栈：SpringCloud

环境：JDK 1.8

一、创建Maven项目

1、File——>New Project ——>Maven 如图所示：

2、填写模块名称和项目路径

 

按照以上步骤，就简单的创建了一个Maven项目。

此时项目还不是SpringBoot项目

二、创建子项目

按同样方法创建子项目，注意组名后面需要在pom中声明。一个最简单的微服务项目结构如下。其中common为实体等单独抽离，其他项目将其作为以来引入的模块。eureka-server为eureka服务端，其他业务模块要作为客户端进行注册。system-management为一个业务模块的样例，其中实现了一个登录接口。

三、配置各模块pom

1、总项目

主要管理各模块和依赖的版本

groupId要改为自己创建项目时的groupId

<?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>com.cloud</groupId>
    <artifactId>cloud-demo</artifactId>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>eureka</module>
        <module>web-server</module>
        <module>common</module>
        <module>system-management</module>
    </modules>
    <packaging>pom</packaging>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <!--<version>1.5.6.RELEASE</version>-->
        <version>1.5.22.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>


    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>com.spotify</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>0.4.3</version>
                <configuration>
                    <skipDockerBuild>true</skipDockerBuild>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

2.common模块

需要指定parent为总项目的artifactId

groupId要改为自己创建项目时的groupId

<?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>cloud-demo</artifactId>
        <groupId>com.cloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>common</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>
</project>

3.eureka-server

工件和组名同理

核心依赖是

eureka-server

其他依赖根据代码需要引入

<?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>cloud-demo</artifactId>
        <groupId>com.cloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>eureka</artifactId>

    <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>Edgware.SR6</spring-cloud.version>

    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka-server</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </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>



</project>

4.微服务模块

工件和组名同理

核心依赖是eureka客户端、Feign客户端、Springboot

和公共模块

<?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>
        <artifactId>cloud-demo</artifactId>
        <groupId>com.cloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <artifactId>system-management</artifactId>
    <name>system-management</name>

    <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>Edgware.SR6</spring-cloud.version>
    </properties>


    <dependencies>
        <!--eureka客户端-->

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>

        <!--数据库配置-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.6</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.4</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.35</version>
        </dependency>

        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>




        <!--springboot配置-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>


        <!--Feign-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-feign</artifactId>
        </dependency>
        <!--公共模块-->
        <dependency>
            <groupId>com.cloud</groupId>
            <artifactId>common</artifactId>
            <version>1.0-SNAPSHOT</version>
            <scope>compile</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>

</project>

5.Feign

核心依赖是

Eureka客户端、Feign服务端、Springboot、公共模块

<?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>cloud-demo</artifactId>
        <groupId>com.cloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>web-server</artifactId>
    <packaging>jar</packaging>
    <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>Edgware.SR6</spring-cloud.version>
    </properties>
    <dependencies>



        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-feign</artifactId>
        </dependency>
        <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>


        <dependency>
            <groupId>com.cloud</groupId>
            <artifactId>common</artifactId>
            <version>1.0-SNAPSHOT</version>
            <scope>compile</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>
</project>

四、配置yml

1.eureka-server

主要作用是配置端口号

server:
  port: 7001
eureka:
  instance:
    hostname: eureka7001.com #eureka服务端的实例名称
  client:
    register-with-eureka: false     #false表示不向注册中心注册自己。
    fetch-registry: false     #false表示自己端就是注册中心，我的职责就是维护服务实例，并不需要去检索服务
    service-url:
      #设置与eureka  server交互的地址和注册服务都需要依赖这个地址
      defaultZone: http://eureka7001.com:7001/eureka/  #单机就是指向自己

2.微服务模块

主要作用是配置端口号和mybatis和数据库

server.port=8099
#server.servlet.context-path=/disk
#spring.web.resources.static-locations=classpath:/templates/, classpath:/static/

spring.application.name=system-management

# MyBatis Configuration
mybatis.mapper-locations=classpath:mapper/*Mapper.xml
mybatis.type-aliases-package=import com.cloud.pojo


# Database Configuration
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=123456

3.Feign

配置端口号即可

各配置文件位置如下

其中system-management是一个微服务模块，web-server为Feign

yml在各模块resources目录下，pom在各模块根目录下

各依赖和配置项最好能了解理解其作用，如果出现问题有助于解决。

版本最好统一管理。

五、业务代码编写

1.eureka启动器

package com.buba.springcloud.eureka;
 
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
 
 
@SpringBootApplication
@EnableEurekaServer
public class EurekaMain {
    public static void main(String[] args) {
        SpringApplication.run(EurekaMain.class,args);
    }
}

2.微服务启动器

package com.study.springcloud.systemmanagement;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;


@SpringBootApplication
@EnableEurekaClient


public class SystemManagementApplication {

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

}

3.Feign启动器

package com.cloud;


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

import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.feign.EnableFeignClients;
import org.springframework.context.annotation.ComponentScan;

//@ComponentScan(basePackages = {"com.study.springcloud.feign"})
//@EnableDiscoveryClient
@SpringBootApplication
@EnableEurekaClient
@EnableFeignClients

//@EnableFeignClients(basePackages = "com.cloud.client")
//@EnableFeignClients(basePackages = {"com.cloud"})

public class WebServerApplication {
    public static void main(String[] args) {

        SpringApplication.run(WebServerApplication.class, args);
    }
}

4.公共类

package com.cloud.pojo;

public class User {
    private int id;
    private String username;
    private String password;

    public User() {
    }
    public User(String username, String password){
        this.username=username;
        this.password=password;
    }


    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

}

5.Feign

5.1FeignClient

package com.cloud.client;


import com.cloud.pojo.User;
import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Controller;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;


@FeignClient(name="system-management",url = "http://localhost:8099")
public interface LoginClient {

    @RequestMapping(value = "/login",method = RequestMethod.GET)
    boolean Login(@RequestParam("username") String username, @RequestParam("password") String password);
}

5.2 Controller 

package com.cloud.controller;



import com.cloud.pojo.User;
import com.cloud.client.LoginClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;

@RestController
@RequestMapping("/webs")

public class LoginController {

    @Autowired
    private LoginClient loginClient;

    @RequestMapping(value = "/login", method = RequestMethod.POST)
    public String Login(HttpServletRequest request){
        //System.out.println("ok");
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        System.out.println("请求中username=："+username);
        User user=new User(username,password);
        System.out.println("读取请求参数构造的user对象："+user);
        System.out.println("读取请求参数构造的user对象的username："+user.getUsername());
        if(loginClient.Login(user.getUsername(),user.getPassword())){
            return "success";
        }
        return "failed";
    }


}

6.微服务

6.1Controller

package com.study.springcloud.systemmanagement.controller;

import com.cloud.pojo.User;
import com.study.springcloud.systemmanagement.service.LoginService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;

@RestController
@RequestMapping
public class LoginController {

    @Autowired
    private LoginService loginService;

    //@RequestMapping(value = "/login", method = RequestMethod.GET)
    @RequestMapping(value = "/login",method = RequestMethod.GET)
    @ResponseBody
    public boolean login(String username,String password) {
//        System.out.println("传给微服务的user："+user);
//        System.out.println("传给微服务的user的username："+user.getUsername());
        System.out.println("传给微服务的username："+username);
        User user_result = this.loginService.login(username, password);
        //System.out.println(user_result);
        return user_result != null;

    }
}

6.2Service

package com.study.springcloud.systemmanagement.service;

import com.cloud.pojo.User;

public interface LoginService {
    User login(String username, String password);
}

6.3Service实例化

package com.study.springcloud.systemmanagement.controller;

import com.cloud.pojo.User;
import com.study.springcloud.systemmanagement.service.LoginService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;

@RestController
@RequestMapping
public class LoginController {

    @Autowired
    private LoginService loginService;

    //@RequestMapping(value = "/login", method = RequestMethod.GET)
    @RequestMapping(value = "/login",method = RequestMethod.GET)
    @ResponseBody
    public boolean login(String username,String password) {
//        System.out.println("传给微服务的user："+user);
//        System.out.println("传给微服务的user的username："+user.getUsername());
        System.out.println("传给微服务的username："+username);
        User user_result = this.loginService.login(username, password);
        //System.out.println(user_result);
        return user_result != null;

    }
}

6.4Dao

package com.study.springcloud.systemmanagement.dao;

import com.cloud.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;

@Mapper
public interface UserDao {

    User login(@Param("username") String username, @Param("password") String password);
}

6.5 mapper.XML 

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.study.springcloud.systemmanagement.dao.UserDao">

    <resultMap id="userMap" type="User">
        <result property="username" column="username"/>
        <result property="password" column="password"/>
    </resultMap>

    <select id="login" resultMap="userMap">
        select username,password
        from user
        where username =#{username} and password =#{password}
    </select>


</mapper>

六、项目运行和使用postman验证

三个服务均能启动

通过postman测试

控制台打印的信息也正常

 

 七、总结

最好初步理解springboot、springcloud架构，以及各组件功能，了解常见依赖后再尝试搭建。

以下为作者个人理解，敬请指正。

搭建时注意各配置文件参数改成自己的。

版本最好使用管理工具统一版本，避免因此出错。

 要有耐心，完事开头难。

作者搭建时遇到过诸多错误，都是一步一步解决的。

譬如mapper.xml配置dao路径错误（不会报错，难以发现）；

EnableFeignClients注解无法扫描到FeignClient，原因是版本不兼容，项目整体重构、各模块统一版本后才得以解决（Springboot和Springcloud组件也有兼容性问题）；

Feign传参给微服务时传不过去值，原因是FeignClient的method参数缺省，底层原理还尚未知晓。