Spring Cloud + Vue前后端分離-第2章使用Maven搭建SpringCloud項目

Maven兩大核心功能：

????????依賴管理（Jar包管理）

????????構建項目（項目打包）

使用Eureka搭建注冊中心

使用spring initializr創建spring cloud項目

SpringCloud和Maven簡介

SpringBoot和SpringCloud：SpringBoot是單應用開發框架，SpringCloud是管理多個SpringBoot應用的微服務框架

GENERATE下載就可以了

下載完成后是個壓縮包，解壓后，打開idea，點擊filer>open就可以導入項目了

項目初始化，要把代碼管理優先做后，不管是學習還是工作，養成階段性提交代碼的習慣。代碼管理選擇git

一個項目里不是所有的文件都需要提交到git，比如.iml這個是idea本地項目文件，比如maven的target文件夾。所以用.gitignore幫我們自動排除

1.增加eureka子模塊作為注冊服務端

2.將單maven項目改造成maven父子項目

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>

搭建業務模塊-system

1.解決注冊中心服務啟動失敗的問題

支持application.properties或application.yml文件，默認會讀取resources目錄下或resources/config目錄下，后續會有讀/config目錄的示例

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

springboot默認集成slf4j框架，它定義了一些日志接口，規范日志輸出，真正的實現是logback或log4j，我們代碼中寫的都是slf4j的代碼

2.優化啟動日志顯示

啟動日志可以按需擴展，甚至可以打印一些有趣的字符圖

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("啟動成功！！");logger.info("Eureka地址: \thttp://127.0.0.1:{}", env.getProperty("server.port"));}}

logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration><!-- 修改一下路徑--><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>

小建議:養成階段性提交代碼的習慣，可以是完成一個小功能。并且每天下班前提交本地代碼，前提是不能編譯報錯或影響已有的功能?

2.新建Maven子項目system

maven父子模塊的配置: 在子模塊中使用parent標簽指向父模塊，在父模塊中使用module標簽引入子模塊

將system配置成最簡單的SpringBoot項目

（注意：java和resources是同級目錄！！！小編大意，求原諒）

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("啟動成功！！");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.將system注冊到注冊中心

第1步:增加eureka-client依賴

第2步:增加配置，指向注冊中心的地址

第3步:增加@EnableEurekaClient

搭建路由模塊-gateway

SpringCloug的網關組件可以用gateway或zuul，最早使用的是zuul，后面spring自己出了gateway

網關主要功能:

????????限流(流量控制)；

????????重試(請求失敗時重試，慎用)；

????????跨域(前后端不在同一個域)；

????????路由(轉發請求)；

????????鑒權(登錄校驗，簽名校驗)等...

新建Maven子項目gateway

步驟和system模塊一樣改一些參數

新增gateway子模塊，增加gateway依賴，并注冊到注冊中心

（注意：java和resources是同級目錄！！！小編大意，求原諒）?

spring.application.name=gateway
server.port=9000
eureka.client.service-url.defaultZone=http://localhost:8761/eureka/#路由轉發
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>