Spring Cloud + Vue前后端分离-第2章使用Maven搭建SpringCloud项目

Maven两大核心功能：

依赖管理（Jar包管理）

构建项目（项目打包）

使用Eureka搭建注册中心

使用spring initializr创建spring cloud项目

SpringCloud和Maven简介

SpringBoot和SpringCloud：SpringBoot是单应用开发框架，SpringCloud是管理多个SpringBoot应用的微服务框架

GENERATE下载就可以了

下载完成后是个压缩包，解压后，打开idea，点击filer>open就可以导入项目了

项目初始化，要把代码管理优先做后，不管是学习还是工作，养成阶段性提交代码的习惯。代码管理选择git

一个项目里不是所有的文件都需要提交到git，比如.iml这个是idea本地项目文件，比如maven的target文件夹。所以用.gitignore帮我们自动排除

1.增加eureka子模块作为注册服务端

2.将单maven项目改造成maven父子项目

pom.xml(course)

<?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><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.2.2.RELEASE</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.course</groupId><artifactId>course</artifactId><version>0.0.1-SNAPSHOT</version><packaging>pom</packaging><name>course</name><description>Demo project for Spring Boot</description><modules><module>eureka</module></modules><properties><java.version>1.8</java.version><spring-cloud.version>Hoxton.RELEASE</spring-cloud.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</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><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build><repositories><repository><id>spring-milestones</id><name>Spring Milestones</name><url>https://repo.spring.io/milestone</url><snapshots><enabled>false</enabled></snapshots></repository></repositories></project>

pom.xml(eureka)

<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>com.course</groupId><artifactId>course</artifactId><version>0.0.1-SNAPSHOT</version></parent><artifactId>eureka</artifactId><packaging>jar</packaging><name>eureka</name><url>http://maven.apache.org</url><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-server</artifactId></dependency></dependencies>
</project>

搭建业务模块-system

1.解决注册中心服务启动失败的问题

支持application.properties或application.yml文件，默认会读取resources目录下或resources/config目录下，后续会有读/config目录的示例

spring.application.name=eureka
server.port=8761
eureka.client.fetch-registry=false
eureka.client.register-with-eureka=false

springboot默认集成slf4j框架，它定义了一些日志接口，规范日志输出，真正的实现是logback或log4j，我们代码中写的都是slf4j的代码

2.优化启动日志显示

启动日志可以按需扩展，甚至可以打印一些有趣的字符图

package com.course;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.env.Environment;/*** Hello world!**/
@SpringBootApplication
@EnableEurekaServer
public class EurekaApplication {private static final Logger logger = LoggerFactory.getLogger(EurekaApplication.class);//    public static void main(String[] args) {
//        SpringApplication.run(EurekaApplication.class, args);
//    }public static void main(String[] args) {SpringApplication app = new SpringApplication(EurekaApplication.class);Environment env = app.run(args).getEnvironment();logger.info("启动成功！！");logger.info("Eureka地址: \thttp://127.0.0.1:{}", env.getProperty("server.port"));}}

logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration><!-- 修改一下路径--><property name="PATH" value="/log/imooc/course/eureka"></property><appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"><encoder>
<!--            <Pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %highlight(%-5level) %blue(%-50logger{50}:%-4line) %msg%n</Pattern>--><Pattern>%d{ss.SSS} %highlight(%-5level) %blue(%-30logger{30}:%-4line) %msg%n</Pattern></encoder></appender><appender name="TRACE_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender"><file>${PATH}/trace.log</file><rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy"><FileNamePattern>${PATH}/trace.%d{yyyy-MM-dd}.%i.log</FileNamePattern><timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP"><maxFileSize>10MB</maxFileSize></timeBasedFileNamingAndTriggeringPolicy></rollingPolicy><layout><pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %-50logger{50}:%-4line %green(%-8X{UUID}) %msg%n</pattern></layout></appender><appender name="ERROR_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender"><file>${PATH}/error.log</file><rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy"><FileNamePattern>${PATH}/error.%d{yyyy-MM-dd}.%i.log</FileNamePattern><timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP"><maxFileSize>10MB</maxFileSize></timeBasedFileNamingAndTriggeringPolicy></rollingPolicy><layout><pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %-50logger{50}:%-4line %green(%-8X{UUID}) %msg%n</pattern></layout><filter class="ch.qos.logback.classic.filter.LevelFilter"><level>ERROR</level><onMatch>ACCEPT</onMatch><onMismatch>DENY</onMismatch></filter></appender><root level="ERROR"><appender-ref ref="ERROR_FILE" /></root><root level="TRACE"><appender-ref ref="TRACE_FILE" /></root><root level="INFO"><appender-ref ref="STDOUT" /></root>
</configuration>

小建议:养成阶段性提交代码的习惯，可以是完成一个小功能。并且每天下班前提交本地代码，前提是不能编译报错或影响已有的功能

2.新建Maven子项目system

maven父子模块的配置: 在子模块中使用parent标签指向父模块，在父模块中使用module标签引入子模块

将system配置成最简单的SpringBoot项目

（注意：java和resources是同级目录！！！小编大意，求原谅）

package com.course.system;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.core.env.Environment;@SpringBootApplicationpublic class SystemApplication {private static final Logger logger = LoggerFactory.getLogger(SystemApplication.class);public static void main(String[] args) {SpringApplication app = new SpringApplication(SystemApplication.class);Environment env = app.run(args).getEnvironment();logger.info("启动成功！！");logger.info("System地址: \thttp://127.0.0.1:{}", env.getProperty("server.port"));}}

spring.application.name=system
server.port=9001

<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>com.course</groupId><artifactId>course</artifactId><version>0.0.1-SNAPSHOT</version></parent><artifactId>system</artifactId><packaging>jar</packaging><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency></dependencies>
</project>

3.将system注册到注册中心

第1步:增加eureka-client依赖

第2步:增加配置，指向注册中心的地址

第3步:增加@EnableEurekaClient

搭建路由模块-gateway

SpringCloug的网关组件可以用gateway或zuul，最早使用的是zuul，后面spring自己出了gateway

网关主要功能:

限流(流量控制)；

重试(请求失败时重试，慎用)；

跨域(前后端不在同一个域)；

路由(转发请求)；

鉴权(登录校验，签名校验)等...

新建Maven子项目gateway

步骤和system模块一样改一些参数

新增gateway子模块，增加gateway依赖，并注册到注册中心

（注意：java和resources是同级目录！！！小编大意，求原谅）

spring.application.name=gateway
server.port=9000
eureka.client.service-url.defaultZone=http://localhost:8761/eureka/#路由转发
spring.cloud.gateway.routes[0].id=system
spring.cloud.gateway.routes[0].uri=http://127.0.0.1:9001
spring.cloud.gateway.routes[0].predicates[0].name=Path
spring.cloud.gateway.routes[0].predicates[0].args[0]=/system/**

<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>com.course</groupId><artifactId>course</artifactId><version>0.0.1-SNAPSHOT</version></parent><artifactId>gateway</artifactId><packaging>jar</packaging><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId></dependency><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-gateway</artifactId></dependency></dependencies>
</project>