springboot微服务合并单体 springboot转微服务

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编程小天匠 2024-03-20 14:55:36

文章标签 springboot微服务合并单体 spring java .net 文章分类 运维

在学习《史上最简单的Spring Cloud教程》时突发奇想，把原来的项目转为微服务

记录学习历程。

1.首先创建一个Maven主工程，在pom文件中添加模块

本机Eclipse中安装了STS即（Spring Tool Suite），在Eclipse中Help->Eclipse MarketPlace->搜索Spring

springboot微服务合并单体 springboot转微服务_spring

可以快速创建SpringBoot应用

先创建一个SpringBoot项目，pom.xml添加SpringCloud版本Finchley,如下

<?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.damionew</groupId>
	<artifactId>Damionew</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>pom</packaging>

	<name>Damionew</name>
	<description>SpringCloud主Maven项目</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.5.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	
	<!-- 引入SpringBoot模块 -->
	<modules>
		<module>damionew-eureka</module>
		<module>service-hi</module>
	</modules>
	
	<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>Finchley.RELEASE</spring-cloud.version>
	</properties>

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

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>


</project>

2.创建两个模块，Eureka服务注册中心和Eureka客户端进行测试

右键主项目，选择new->other->收入Maven Module搜索添加

如果出现

The parent project must have a packaging type of POM

则是因为在主项目中packing属性不是pom，修改即可

springboot微服务合并单体 springboot转微服务_spring_02

springboot微服务合并单体 springboot转微服务_java_03

next->next->next

生成pom，整理并添加eureka-server依赖

发现会报'dependencies.dependency.version' is missing for xxx的错误，检查后找到原因是：在主项目的pom.xml中没有添加

<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>

进行依赖版本控制，添加后解决

在服务注册中心的启动类中添加@EnableEurekaServer以开启SpringCloud Eureka Server

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

@SpringBootApplication
@EnableEurekaServer
public class DamionewEurekaApplication {

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

包名不能有-，稍作调整，调整为SpringBoot项目结构即可

此时项目结构如图

springboot微服务合并单体 springboot转微服务_spring_04

配置application.properties

# 应用程序名称
#spring.application.name=eureka-server
# 应用端口
server.port=8001
spring.freemarker.prefer-file-system-access=false
# 服务注册中心配置
# 服务注册中心实例的主机名
eureka.instance.hostname=localhost
# 是否向服务注册中心注册自己
eureka.client.register-with-eureka=false
# 是否检索服务
eureka.client.fetch-registry=false
# 服务中心的配置内容，指定服务注册中心的位置
eureka.client.service-url.defaultZone:http://${eureka.instance.hostname}:${server.port}/eureka/

但是当启动项目后，访问localhost:8001时报404

搞了很久不得其解

先试着做了一下Eureka Client，发现可以找到服务注册中心，只是服务注册中心无法进入管理页面

如下

springboot微服务合并单体 springboot转微服务_java_05

pom.xml，因为加了一个Controller测试所以加了-web的依赖，另外此处引用Eureka的客户端依赖

<?xml version="1.0"?>
<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <modelVersion>4.0.0</modelVersion>
  
  <groupId>com.damionew</groupId>
  <artifactId>Damionew-Hi</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>Damionew-Hi</name>
  <url>http://maven.apache.org</url>
  
  <parent>
    <groupId>com.damionew</groupId>
    <artifactId>Damionew</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>
  
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <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>

启动类

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@EnableEurekaClient
@SpringBootApplication
@RestController
public class HiApplication {

	public static void main(String[] args) {
		SpringApplication.run(HiApplication.class, args);
	}
	
	@Value("${server.port}")
	String port;
	
	@RequestMapping("/hi")
	public String hi() {
		return "hi";
	}
}

配置文件，注意端口要和服务注册中心端口不同，并且eureka.client.service-url.defaultZone使用服务注册中心地址

# 应用程序名称
spring.application.name=eureka-server
# 应用端口
server.port=8002

eureka.client.service-url.defaultZone:http://localhost:8001/eureka/

启动Eureka和Hi项目后可以通过控制台查看

Hi项目打印

2018-09-13 17:18:39.698  INFO 20064 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_EUREKA-SERVER/localhost:eureka-server:8002: registering service...
2018-09-13 17:18:39.835  INFO 20064 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8002 (http) with context path ''
2018-09-13 17:18:39.839  INFO 20064 --- [           main] .s.c.n.e.s.EurekaAutoServiceRegistration : Updating port to 8002
2018-09-13 17:18:39.846  INFO 20064 --- [           main] com.hi.HiApplication                     : Started HiApplication in 12.78 seconds (JVM running for 14.074)
2018-09-13 17:18:39.924  INFO 20064 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_EUREKA-SERVER/localhost:eureka-server:8002 - registration status: 204

如果没有连接到服务注册中心，会连续报错，而服务注册中心有心跳检测功能，每隔几秒就会检测一次

com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server
	at com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:112) ~[eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getDelta(EurekaHttpClientDecorator.java:149) ~[eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$7.execute(EurekaHttpClientDecorator.java:152) ~[eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77) ~[eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.getDelta(EurekaHttpClientDecorator.java:149) ~[eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.DiscoveryClient.getAndUpdateDelta(DiscoveryClient.java:1085) [eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.DiscoveryClient.fetchRegistry(DiscoveryClient.java:967) [eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.DiscoveryClient.refreshRegistry(DiscoveryClient.java:1471) [eureka-client-1.9.2.jar:1.9.2]
	at com.netflix.discovery.DiscoveryClient$CacheRefreshThread.run(DiscoveryClient.java:1438) [eureka-client-1.9.2.jar:1.9.2]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_144]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_144]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_144]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_144]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_144]

但是没有Eureka管理页面真的很难受

修改了一下pom文件，将spring改为1.X且Cloud改为Brixton.SR5后管理页面就出来了。

到家以后换了个电脑发现，用原来的版本就可以显示

springboot微服务合并单体 springboot转微服务_.net_06