springCloud Finchley microservice architecture from entry to mastery [2] Eureka service registration and discovery

1. Description of development tools

To prevent the code from running incorrectly, it is recommended to use a consistent version:

• Development tools: Eclipse : Version: Neon.3 Release (4.6.3) It
  is recommended to use idea or the STS tools officially provided by spring to develop spring cloud applications. The author chose Eclipse to install the STS plug-in due to the company's internal usage habits and other reasons.

• STS plug-in download address: http://spring.io/tools/sts/all/
  Note here: STS plug-in should choose the version corresponding to Eclipse:

• JDK ： jdk1_8_131

• MAVEN ： maven 3.5

2. Create the Eureka registry

1. Create a Maven main project

Delete the src package in its directory, leaving only pom.xml

Here, the package selects pom, and finally its sub-projects have repeated dependencies and are uniformly extracted here. This is the main role of the main project.

2. Create a springboot project on the main project

Select Eureka Server , the project is created

At this point pom.xml is:

<?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.mayi.springcloud</groupId>
    <artifactId>commonservice-eureka</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>commonservice-eureka</name>
    <description>eureka 注册中心</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <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.M9</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>

        <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>

3 、 配置 bootstrap.yml

Rename application.properties in the resources directory to bootstrap.yml (recommended to use formatted ymal language, think about the benefits yourself ^_^), ymal verification is relatively strict, mine is a line break and two spaces, keep it uniform, and the editor is also with hints

server:
  port: 8761
spring:
  application:
    name: service-registry
eureka:
  instance:
    prefer-ip-address: true
  client:
    fetch-registry: false
    register-with-eureka: false
  server:
    wait-time-in-ms-when-sync-empty: 0

explain:

• 配置为server :
  fetch-registry: false
  register-with-eureka: false

4. Startup class configuration

Just add the @EnableEurekaServer annotation

package com.mayi.springcloud;


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

@SpringBootApplication
@EnableEurekaServer
public class CommonserviceEurekaApplication {

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

Start with SpringBootApp, access address: localhost:8761

Open the above webpage normally, indicating that the Eureka registration center is successfully configured.

3. Create a client project

1. pom.xml is the same as above, and the simple code of bootstrap.yml is as follows:

spring:
  application:
    name: service-eureka-client
server:
  port: 8800

2. Add the @EnableEurekaClient annotation to the startup class

It is recommended to use the @EnableEurekaClient annotation to declare the client, because we are using the Eureka registry. If you use zookeeper or other registries, use @EnableDiscoveryClient , and for the Eureka registry, both can be

package com.mayi.springcloud;

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

@SpringBootApplication
@EnableEurekaClient
public class CommonserviceEurekaClientApplication {

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

3. Start the project

As shown in the figure, the client registration is successful:

Next, I will revise new articles in turn until the whole structure is completed. If you are interested, add me on WeChat and join the spring cloud community group.

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