初识SpringCloud

Spring Cloud 是一套残缺的微服务解决方案,基于 Spring Boot 框架,精确的说,它不是一个框架,而是一个大的容器,它将市面上较好的微服务框架集成进来,从而简化了开发者的代码量。

Spring Cloud 是什么?

Spring Cloud 是一系列框架的有序汇合,它利用 Spring Boot 的开发便利性简化了分布式系统的开发,比方服务发现、服务网关、服务路由、链路追踪等。Spring Cloud 并不反复造轮子,而是将市面上开发得比拟好的模块集成进去,进行封装,从而缩小了各模块的开发成本。换句话说:Spring Cloud 提供了构建分布式系统所需的“全家桶”。

Spring Cloud 现状

目前,国内应用 Spring Cloud 技术的公司并不多见,不是因为 Spring Cloud 不好,次要起因有以下几点:

  • Spring Cloud 中文文档较少,呈现问题网上没有太多的解决方案。
  • 国内守业型公司技术老大大多是阿里系员工,而阿里系多采纳 Dubbo 来构建微服务架构。
  • 大型公司根本都有本人的分布式解决方案,而中小型公司的架构很多用不上微服务,所以没有采纳 Spring Cloud 的必要性。

然而,微服务架构是一个趋势,而 Spring Cloud 是微服务解决方案的佼佼者.

Spring Cloud 优缺点

长处

  • 集大成者,Spring Cloud 蕴含了微服务架构的方方面面。
  • 约定优于配置,基于注解,没有配置文件。
  • 轻量级组件,Spring Cloud 整合的组件大多比拟轻量级,且都是各自畛域的佼佼者。
  • 开发简便,Spring Cloud 对各个组件进行了大量的封装,从而简化了开发。
  • 开发灵便,Spring Cloud 的组件都是解耦的,开发人员能够灵便按需抉择组件。

毛病

  • 我的项目结构复杂,每一个组件或者每一个服务都须要创立一个我的项目。
  • 部署门槛高,我的项目部署须要配合 Docker 等容器技术进行集群部署,而要想深刻理解 Docker,学习老本高。

Spring Cloud 的劣势是不言而喻的。学习 Spring Cloud 是一个不错的抉择。

Spring Cloud 和 Dubbo 比照

Dubbo 只是实现了服务治理,而 Spring Cloud 实现了微服务架构的方方面面,服务治理只是其中的一个方面。上面通过一张图对其进行比拟:

能够看出,Spring Cloud 比拟全面,而 Dubbo 因为只实现了服务治理,须要集成其余模块,须要独自引入,减少了学习老本和集成老本。

我的项目构造

父我的项目pom

<?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>    <parent>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-parent</artifactId>        <version>2.1.4.RELEASE</version>        <relativePath/> <!-- lookup parent from repository -->    </parent>    <groupId>cn.com.codingce</groupId>    <artifactId>springcloud</artifactId>    <version>1.0-SNAPSHOT</version>    <modules>        <module>springcloud-api</module>        <module>springcloud-provider-dept</module>        <module>springcloud-consumer-dept</module>    </modules>    <!--打包形式-->    <packaging>pom</packaging>    <!--对立配置 版本号-->    <properties>        <junit.version>4.12</junit.version>        <lombok.version>1.16.10</lombok.version>        <mysql.version>8.0.11</mysql.version>        <druid.version>1.1.10</druid.version>        <logbackcore.version>1.2.3</logbackcore.version>    </properties>    <dependencyManagement>        <dependencies>            <!-- springcloud的依赖 -->            <dependency>                <groupId>org.springframework.cloud</groupId>                <artifactId>spring-cloud-dependencies</artifactId>                <version>Greenwich.SR1</version>                <type>pom</type>                <scope>import</scope>            </dependency>            <!--springboot依赖-->            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-dependencies</artifactId>                <scope>2.1.4.RELEASE</scope>            </dependency>            <!--连贯数据库-->            <dependency>                <groupId>mysql</groupId>                <artifactId>mysql-connector-java</artifactId>                <version>${mysql.version}</version>            </dependency>            <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->            <dependency>                <groupId>com.alibaba</groupId>                <artifactId>druid</artifactId>                <version>${druid.version}</version>            </dependency>            <!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->            <dependency>                <groupId>org.mybatis.spring.boot</groupId>                <artifactId>mybatis-spring-boot-starter</artifactId>                <version>1.3.2</version>            </dependency>            <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-core -->            <dependency>                <groupId>ch.qos.logback</groupId>                <artifactId>logback-core</artifactId>                <version>1.2.3</version>            </dependency>            <!-- https://mvnrepository.com/artifact/junit/junit -->            <dependency>                <groupId>junit</groupId>                <artifactId>junit</artifactId>                <version>${junit.version}</version>            </dependency>            <dependency>                <groupId>org.projectlombok</groupId>                <artifactId>lombok</artifactId>                <version>${lombok.version}</version>            </dependency>            <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-devtools -->            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-devtools</artifactId>                <version>2.2.2.RELEASE</version>            </dependency>            <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-jetty -->            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-starter-jetty</artifactId>                <version>2.0.1.RELEASE</version>            </dependency>            <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-starter-web</artifactId>                <version>2.0.1.RELEASE</version>            </dependency>            <dependency>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-devtools</artifactId>                <version>2.1.4.RELEASE</version>            </dependency>        </dependencies>    </dependencyManagement></project>

实体类

pom

<?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>springcloud</artifactId>        <groupId>cn.com.codingce</groupId>        <version>1.0-SNAPSHOT</version>    </parent>    <modelVersion>4.0.0</modelVersion>    <artifactId>springcloud-api</artifactId>    <dependencies>        <!--以后module本人须要的依赖, 如果父依赖中曾经配置了版本-->        <dependency>            <groupId>org.projectlombok</groupId>            <artifactId>lombok</artifactId>        </dependency>        <!--junit--><!--        <dependency>--><!--            <groupId>junit</groupId>--><!--            <artifactId>junit</artifactId>--><!--        </dependency>-->        <dependency>            <groupId>mysql</groupId>            <artifactId>mysql-connector-java</artifactId>        </dependency>        <dependency>            <groupId>com.alibaba</groupId>            <artifactId>druid</artifactId>        </dependency>    </dependencies></project>

Dept

package cn.com.codingce.pojo;import lombok.experimental.Accessors;import java.io.Serializable;/** * @author xzMa * Dept实体类 orm  类表关系映射 */@Accessors  //链式写法public class Dept implements Serializable {    private Long deptno;    private String dname;    private String db_source;    /**     * Dept dept = new Dept();     * dept.setDeptNo("").setDeptyName().....  都行     */    public Dept() {    }    public Dept(Long deptno, String dname, String db_source) {        this.deptno = deptno;        this.dname = dname;        this.db_source = db_source;    }    public Long getDeptno() {        return deptno;    }    public void setDeptno(Long deptno) {        this.deptno = deptno;    }    public String getDname() {        return dname;    }    public void setDname(String dname) {        this.dname = dname;    }    public String getDb_source() {        return db_source;    }    public void setDb_source(String db_source) {        this.db_source = db_source;    }    @Override    public String toString() {        return "Dept{" +                "deptno=" + deptno +                ", dname='" + dname + '\'' +                ", db_source='" + db_source + '\'' +                '}';    }}

服务端

pom

<?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>springcloud</artifactId>        <groupId>cn.com.codingce</groupId>        <version>1.0-SNAPSHOT</version>    </parent>    <modelVersion>4.0.0</modelVersion>    <artifactId>springcloud-provider-dept</artifactId>    <dependencies>        <!--咱们须要拿到实体类, 所以要配置api -module-->        <dependency>            <groupId>cn.com.codingce</groupId>            <artifactId>springcloud-api</artifactId>            <version>1.0-SNAPSHOT</version>        </dependency>        <!--junit-->        <dependency>            <groupId>junit</groupId>            <artifactId>junit</artifactId>        </dependency>        <dependency>            <groupId>mysql</groupId>            <artifactId>mysql-connector-java</artifactId>        </dependency>        <dependency>            <groupId>com.alibaba</groupId>            <artifactId>druid</artifactId>        </dependency>        <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-core -->        <dependency>            <groupId>ch.qos.logback</groupId>            <artifactId>logback-core</artifactId>        </dependency>        <dependency>            <groupId>org.mybatis.spring.boot</groupId>            <artifactId>mybatis-spring-boot-starter</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-test</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency><!--        &lt;!&ndash;jetty&ndash;&gt;--><!--        &lt;!&ndash; https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-jetty &ndash;&gt;-->        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-jetty</artifactId>        </dependency>        <!--热部署工具-->        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-devtools</artifactId>        </dependency>    </dependencies></project>

Controller

package cn.com.codingce.controller;import cn.com.codingce.pojo.Dept;import cn.com.codingce.service.DeptService;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.PostMapping;import org.springframework.web.bind.annotation.RestController;import javax.annotation.Resource;import java.util.List;/** * @author xzMa * * 提供RestFul服务 */@RestControllerpublic class DeptController {    @Resource    private DeptService deptService;    @PostMapping("/dept/add")    public boolean addDept(Dept dept) {        return deptService.addDept(dept);    }    @GetMapping("/dept/get/{id}")    public Dept queryBuId(@PathVariable("id") Long id) {        return deptService.queryById(id);    }    @GetMapping("/dept/list")    public List<Dept> queryAll() {        return deptService.queryAll();    }}

DAO (mapper)

package cn.com.codingce.dao;import cn.com.codingce.pojo.Dept;import org.apache.ibatis.annotations.Mapper;import org.springframework.stereotype.Repository;import java.util.List;@Mapper@Repositorypublic interface DeptDao {    public boolean addDept(Dept dept);    public Dept queryById(Long id);    public List<Dept> queryAll();}

Mapper.xml

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE mapper        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mapper namespace="cn.com.codingce.dao.DeptDao">    <insert id="addDept" parameterType="Dept">        insert into dept(dname, db_source) values (#{dname}, DATABASE())    </insert>        <select id="queryById" parameterType="Long" resultType="Dept">        select * from dept where deptno = #{deptno}    </select>    <select id="queryAll" resultType="Dept">        select * from dept    </select></mapper>

Service接口

package cn.com.codingce.service;import cn.com.codingce.pojo.Dept;import java.util.List;public interface DeptService {    public boolean addDept(Dept dept);    public Dept queryById(Long id);    public List<Dept> queryAll();}

Service实现类

package cn.com.codingce.service;import cn.com.codingce.dao.DeptDao;import cn.com.codingce.pojo.Dept;import org.springframework.stereotype.Service;import javax.annotation.Resource;import java.util.List;@Servicepublic class DeptServiceImpl implements DeptService {    @Resource    private DeptDao deptDao;    @Override    public boolean addDept(Dept dept) {        return deptDao.addDept(dept);    }    @Override    public Dept queryById(Long id) {        return deptDao.queryById(id);    }    @Override    public List<Dept> queryAll() {        return deptDao.queryAll();    }}

mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE configuration        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-config.dtd"><!--外围配置文件--><configuration>    <!--开启二级缓存-->    <settings>        <setting name="cacheEnabled" value="true"/>        <setting name="logImpl" value="STDOUT_LOGGING"/>    </settings></configuration>

application.yml

server:  port: 8001#mybatis配置mybatis:  type-aliases-package: cn.com.codingce.pojo  config-location: classpath:mybatis/mybatis-config.xml  mapper-locations: classpath:mybatis/mapper/*.xml#  configuration:#    map-underscore-to-camel-case: true# spring配置spring:  application:    name: springcloud-provider-dept  datasource:    type: com.alibaba.druid.pool.DruidDataSource # 数据源 德鲁伊    driver-class-name: com.mysql.jdbc.Driver    url: jdbc:mysql://cdb-q9atzwrq.bj.tencentcdb.com:10167/db01?useSSL=true    username: root    password: 123456

客户端

pom

<?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>springcloud</artifactId>        <groupId>cn.com.codingce</groupId>        <version>1.0-SNAPSHOT</version>    </parent>    <modelVersion>4.0.0</modelVersion>    <artifactId>springcloud-consumer-dept</artifactId>    <dependencies>        <!--咱们须要拿到实体类, 所以要配置api -module-->        <dependency>            <groupId>cn.com.codingce</groupId>            <artifactId>springcloud-api</artifactId>            <version>1.0-SNAPSHOT</version>        </dependency>        <!--热部署工具-->        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-devtools</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency>    </dependencies></project>

配置文件

package cn.com.codingce.config;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.web.client.RestTemplate;@Configurationpublic class ConfigBean {   //configuration -- spring applicationContext.xml    @Bean    public RestTemplate getRestTemplate() {        return new RestTemplate();    }}

Controller

package cn.com.codingce.controller;import cn.com.codingce.pojo.Dept;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import org.springframework.web.client.RestTemplate;import java.util.List;@RestControllerpublic class DeptConsumerController {    // 了解消费者, 不应该有service层    //RestFul格调    //(url, 实体: Map classs<T> responseType)    @Autowired    private RestTemplate restTemplate;  //提供多种便捷拜访近程http服务的办法    private static final String REST_URL_PREFIX = "http://localhost:8001";    @RequestMapping("/consumer/dept/add")    public boolean add(Dept dept) {        return restTemplate.postForObject(REST_URL_PREFIX + "/dept/add", dept, Boolean.class);    }    //http://localhost:8001/dept/list    @RequestMapping("/consumer/dept/get/{id}")    public Dept get(@PathVariable("id") Long id) {        return restTemplate.getForObject(REST_URL_PREFIX + "/dept/get/" + id, Dept.class );    }    @RequestMapping("/consumer/dept/list")    public List<Dept> list() {        return restTemplate.getForObject(REST_URL_PREFIX + "/dept/list" , List.class );    }}

application.yml

server:  port: 80