[Java知识库]Java实战：微服务多模块项目搭建（一）

入行7年，从Delphi到Java，再到前端，全栈，一路走来，磕磕碰碰。回顾一下过去，总结经验，继续学习、前进。

以一个全栈工程师的角度，记录下如何在一个传统公司或中小型公司独立快速开发系统，独当一面，包括前端、后端、数据库、小程序等，遇到的问难和解决方案也会分享在此，希望对有需要的朋友有所帮助（大佬们无视~）！

该系列文章适合有一定Java基础和SpringBoot开发经验的人。另外由于是以一个比较完整的项目作为例子，所以许多搭建细节不作描述。

开发环境：Idea2020、JDK11（Idea2017、JDK8也可以）

技术栈：SpringBoot、Alibaba Cloud、Nacos、Redis、Vue、ElementUI

数据库：PostgreSQL10

开始吧！

项目创建

一、创建Maven项目

1.pom文件中配置版本信息和依赖（是最顶层模块的pom）

<!-- ?般来说?级项?的packaging都为pom，packaging默认类型jar类型-->
    <packaging>pom</packaging>
    <version>1.0.0</version>
    <modules>
        <!-- 业务中心 -->
        <module>business-center</module>
        <!-- 公共模块 -->
        <module>common-center</module>
        <!-- api网关 -->
        <module>api-gateway</module>
    </modules>

    <properties>
        <java.version>11</java.version>
        <maven.compiler.source>11</maven.compiler.source>
        <maven.compiler.target>11</maven.compiler.target>
        <spring.boot.version>2.3.3.RELEASE</spring.boot.version>
        <spring.cloud.version>Hoxton.SR8</spring.cloud.version>
        <alibaba.cloud.version>2.2.1.RELEASE</alibaba.cloud.version>
        <mybatisplus.boot.starter.version>3.4.0</mybatisplus.boot.starter.version>
        <lombok.version>1.18.16</lombok.version>
        <commons.lang3.version>3.9</commons.lang3.version>
        <commons.codec.version>1.15</commons.codec.version>
        <springfox.boot.starter.version>3.0.0</springfox.boot.starter.version>
        <!--跳过单元测试-->
        <skipTests>true</skipTests>
    </properties>

    <!--锁定版本-->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring.boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

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

            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${alibaba.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <!--mybatis plus和springboot整合-->
            <dependency>
                <groupId>com.baomidou</groupId>
                <artifactId>mybatis-plus-boot-starter</artifactId>
                <version>${mybatisplus.boot.starter.version}</version>
            </dependency>

            <!--scope=provided，说明它只在编译阶段生效，不需要打入包中, Lombok在编译期将带Lombok注解的Java文件正确编译为完整的Class文件-->
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok.version}</version>
                <!--<scope>provided</scope>-->
            </dependency>

            <dependency>
                <groupId>org.apache.commons</groupId>
                <artifactId>commons-lang3</artifactId>
                <version>${commons.lang3.version}</version>
            </dependency>

            <!--接口文档依赖-->
            <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-boot-starter</artifactId>
                <version>${springfox.boot.starter.version}</version>
            </dependency>

            <!--aliyun oss-->
            <dependency>
                <groupId>com.aliyun.oss</groupId>
                <artifactId>aliyun-sdk-oss</artifactId>
                <version>3.10.2</version>
            </dependency>

            <!-- JWT相关 -->
            <dependency>
                <groupId>io.jsonwebtoken</groupId>
                <artifactId>jjwt</artifactId>
                <version>0.7.0</version>
            </dependency>

            <!--kaptcha依赖包-->
            <dependency>
                <groupId>com.baomidou</groupId>
                <artifactId>kaptcha-spring-boot-starter</artifactId>
                <version>1.1.0</version>
            </dependency>

            <!--用于加密-->
            <dependency>
                <groupId>commons-codec</groupId>
                <artifactId>commons-codec</artifactId>
                <version>${commons.codec.version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <!-- 代码库 -->
    <repositories>
        <repository>
            <id>maven-ali</id>
            <url>http://maven.aliyun.com/nexus/content/groups/public//</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>true</enabled>
                <updatePolicy>always</updatePolicy>
                <checksumPolicy>fail</checksumPolicy>
            </snapshots>
        </repository>
    </repositories>

    <pluginRepositories>
        <pluginRepository>
            <id>public</id>
            <name>aliyun nexus</name>
            <url>http://maven.aliyun.com/nexus/content/groups/public/</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </pluginRepository>
    </pluginRepositories>

    <!--module不用添加打包版本信息-->
    <build>
        <finalName>${artifactId}</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>${spring.boot.version}</version>
                <configuration>
                    <fork>true</fork>
                    <addResources>true</addResources>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>11</source>
                    <target>11</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

2.common-center配置

<properties>
        <maven.compiler.source>11</maven.compiler.source>
        <maven.compiler.target>11</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <!--lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!--mybatis-plus-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
        </dependency>
        <!--mysql-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--postgresql-->
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
        </dependency>
        <!-- 代码自动生成依赖 begin -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-generator</artifactId>
            <version>3.4.1</version>
        </dependency>
        <!-- velocity -->
        <dependency>
            <groupId>org.apache.velocity</groupId>
            <artifactId>velocity-engine-core</artifactId>
            <version>2.0</version>
        </dependency>
        <!-- 代码自动生成依赖 end-->
        <!--swagger ui接口文档依赖-->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-boot-starter</artifactId>
        </dependency>
        <!--redis客户端-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>io.lettuce</groupId>
                    <artifactId>lettuce-core</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.12.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>commons-collections</groupId>
            <artifactId>commons-collections</artifactId>
            <version>3.2.2</version>
        </dependency>
        <!--添加nacos客户端-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!--配置中心-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>
        <!--Feign远程调用-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.58</version>
        </dependency>
        <!--用于加密-->
        <dependency>
            <groupId>commons-codec</groupId>
            <artifactId>commons-codec</artifactId>
        </dependency>
        <!-- JWT相关 -->
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
        </dependency>
        <!--邮箱-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
    </dependencies>

3.api-gateway配置

    <properties>
        <maven.compiler.source>11</maven.compiler.source>
        <maven.compiler.target>11</maven.compiler.target>
    </properties>

    <dependencies>
        <!--网关依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>

        <!--添加nacos客户端-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>

        <!--配置中心-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>
    </dependencies>

4.business-center业务中心，创建一些业务服务模块，这里以user-center用户服务为例

    <artifactId>business-center</artifactId>
    <description>业务中心</description>
    <modules>
        <module>user-center</module>
    </modules>
    <packaging>pom</packaging>

    <properties>
        <maven.compiler.source>11</maven.compiler.source>
        <maven.compiler.target>11</maven.compiler.target>
    </properties>

5.user-center用户服务

    <dependencies>
        <dependency>
            <groupId>net.work</groupId>
            <artifactId>common-center</artifactId>
            <version>1.0.0</version>
        </dependency>

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>kaptcha-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>com.aliyun.oss</groupId>
            <artifactId>aliyun-sdk-oss</artifactId>
        </dependency>
    </dependencies>

二、创建基础的包和启动类

1.依赖包都下载好后，将基础的包和启动类创建出来

package net.work;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@SpringBootApplication
@EnableDiscoveryClient
@MapperScan("net.work.mapper")
@EnableTransactionManagement
public class UserCenterApp {
    public static void main(String[] args) {
        SpringApplication.run(UserCenterApp.class, args);
    }
}

package net.work;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@SpringBootApplication
@EnableDiscoveryClient
public class GatewayServerApp {
    public static void main(String[] args) {
        SpringApplication.run(GatewayServerApp.class, args);
    }
}

2.配置文件

application.yml不需要写任何内容，基本上没有特殊配置，bootstrap.yml中的配置都大同小异

（1）网关服务

spring:
  application:
    name: api-gateway-service
  cloud:
    nacos:
      config:
        server-addr: localhost:8848 #Nacos配置中心地址（本地）
        file-extension: yaml #文件拓展格式

#  profiles:
#    active: dev #本地开发环境
#    active: pro #线上生产环境

（2）用户服务

spring:
  application:
    name: user-service
  cloud:
    nacos:
      config:
        server-addr: localhost:8848 #Nacos配置中心地址（本地）
        file-extension: yaml #文件拓展格式

#  profiles:
#    active: dev #本地开发环境
#    active: pro #线上生产环境

下一次，整合Nacos，让项目跑起来！