spring spring-boot kotlin netflix-eureka

Cannot launch Eureka server because of connection refused, Exception: com.sun.jersey.api.client.ClientHandlerException

I am trying to launch a simple Eureka server via Spring Cloud Netflix and in Kotlin, but I keep receiving Request execution error. endpoint=DefaultEndpoint{ serviceUrl='http://localhost:8761/eureka/}, exception=java.net.ConnectException: Connection refused stacktrace=com.sun.jersey.api.client.ClientHandlerException: java.net.ConnectException: Connection refused, no matter how many times I change my application.properties in a variety of different ways, with the help of multiple posts on here. How can I fix this?

My pom.xml:

<?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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.3</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>2021.0.4</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <artifactId>discovery-server</artifactId>
    <groupId>org.shopping</groupId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <name>discovery-server</name>

    <properties>
        <java.version>11</java.version>
        <kotlin.version>1.6.21</kotlin.version>
        <spring-cloud.version>2021.0.4</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-reflect</artifactId>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-stdlib-jdk8</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-bootstrap</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
        <testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>org.jetbrains.kotlin</groupId>
                <artifactId>kotlin-maven-plugin</artifactId>
                <configuration>
                    <args>
                        <arg>-Xjsr305=strict</arg>
                    </args>
                    <compilerPlugins>
                        <plugin>spring</plugin>
                    </compilerPlugins>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>org.jetbrains.kotlin</groupId>
                        <artifactId>kotlin-maven-allopen</artifactId>
                        <version>${kotlin.version}</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>
    </build>

</project>

My DiscoveryServerApplication:

package com.shopping.discoveryserver

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

@SpringBootApplication
@EnableEurekaServer
class DiscoveryServerApplication

fun main(args: Array<String>) {
    runApplication<DiscoveryServerApplication>(*args)
}

My application.properties:

server.port=8761
spring.application.name=eureka-server
eureka.instance.hostname=localhost
eureka.server.maxThreadsForPeerReplication=0
eureka.client.registerWithEureka=false
eureka.client.fetchRegistry=false

Spring Boot log:

2022-10-17 00:17:38.665  INFO 81886 --- [           main] c.c.c.ConfigServicePropertySourceLocator : Fetching config from server at : http://localhost:8888
2022-10-17 00:17:38.743  INFO 81886 --- [           main] c.c.c.ConfigServicePropertySourceLocator : Connect Timeout Exception on Url - http://localhost:8888. Will be trying the next url if available
2022-10-17 00:17:38.743  WARN 81886 --- [           main] c.c.c.ConfigServicePropertySourceLocator : Could not locate PropertySource: I/O error on GET request for "http://localhost:8888/application/default": Connection refused; nested exception is java.net.ConnectException: Connection refused
2022-10-17 00:17:38.745  INFO 81886 --- [           main] c.s.d.DiscoveryServerApplicationKt       : No active profile set, falling back to 1 default profile: "default"
2022-10-17 00:17:39.393  INFO 81886 --- [           main] o.s.cloud.context.scope.GenericScope     : BeanFactory id=c3bbf1c6-4eb5-3807-b805-19115a4714b1
2022-10-17 00:17:39.606  INFO 81886 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2022-10-17 00:17:39.613  INFO 81886 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2022-10-17 00:17:39.614  INFO 81886 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.65]
2022-10-17 00:17:39.723  INFO 81886 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2022-10-17 00:17:39.723  INFO 81886 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 963 ms
2022-10-17 00:17:40.044  INFO 81886 --- [           main] c.s.j.s.i.a.WebApplicationImpl           : Initiating Jersey application, version 'Jersey: 1.19.4 05/24/2017 03:20 PM'
2022-10-17 00:17:40.093  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using JSON encoding codec LegacyJacksonJson
2022-10-17 00:17:40.093  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using JSON decoding codec LegacyJacksonJson
2022-10-17 00:17:40.192  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using XML encoding codec XStreamXml
2022-10-17 00:17:40.192  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using XML decoding codec XStreamXml
2022-10-17 00:17:40.882  INFO 81886 --- [           main] DiscoveryClientOptionalArgsConfiguration : Eureka HTTP Client uses Jersey
2022-10-17 00:17:40.927  WARN 81886 --- [           main] iguration$LoadBalancerCaffeineWarnLogger : Spring Cloud LoadBalancer is currently working with the default cache. While this cache implementation is useful for development and tests, it's recommended to use Caffeine cache in production.You can switch to using Caffeine cache, by adding it and org.springframework.cache.caffeine.CaffeineCacheManager to the classpath.
2022-10-17 00:17:40.939  INFO 81886 --- [           main] o.s.c.n.eureka.InstanceInfoFactory       : Setting initial instance status as: STARTING
2022-10-17 00:17:40.972  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Initializing Eureka in region us-east-1
2022-10-17 00:17:41.089  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using JSON encoding codec LegacyJacksonJson
2022-10-17 00:17:41.089  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using JSON decoding codec LegacyJacksonJson
2022-10-17 00:17:41.089  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using XML encoding codec XStreamXml
2022-10-17 00:17:41.089  INFO 81886 --- [           main] c.n.d.provider.DiscoveryJerseyProvider   : Using XML decoding codec XStreamXml
2022-10-17 00:17:41.172  INFO 81886 --- [           main] c.n.d.s.r.aws.ConfigClusterResolver      : Resolving eureka endpoints via configuration
2022-10-17 00:17:41.183  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Disable delta property : false
2022-10-17 00:17:41.183  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Single vip registry refresh property : null
2022-10-17 00:17:41.184  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Force full registry fetch : false
2022-10-17 00:17:41.184  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Application is null : false
2022-10-17 00:17:41.184  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Registered Applications size is zero : true
2022-10-17 00:17:41.184  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Application version is -1: true
2022-10-17 00:17:41.184  INFO 81886 --- [           main] com.netflix.discovery.DiscoveryClient    : Getting all instance registry info from the eureka server
2022-10-17 00:17:41.228  INFO 81886 --- [           main] c.n.d.s.t.d.RedirectingEurekaHttpClient  : Request execution error. endpoint=DefaultEndpoint{ serviceUrl='http://localhost:8761/eureka/}, exception=java.net.ConnectException: Connection refused stacktrace=com.sun.jersey.api.client.ClientHandlerException: java.net.ConnectException: Connection refused
...
    at com.shopping.discoveryserver.DiscoveryServerApplicationKt.main(DiscoveryServerApplication.kt:15)
Caused by: java.net.ConnectException: Connection refused

Solution

I figured it out, and since this seems to be an unanswered & common question on here, I will post my pom & properties file on here (adapted from Cannot connect to Eureka server. Exception: java.net.ConnectException: Connection refused: connect):

My pom.xml:

<?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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <artifactId>api-discovery</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>discovery-server</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>11</java.version>
        <kotlin.version>1.6.21</kotlin.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-reflect</artifactId>
        </dependency>
        <dependency>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-stdlib-jdk8</artifactId>
        </dependency>
        <dependency>
            <!-- Setup Spring Boot -->
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <!-- Setup Spring MVC & REST, use Embedded Tomcat -->
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <!-- Spring Cloud starter -->
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka-server</artifactId>
            <version>1.4.6.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.2.11</version>
        </dependency>
        <dependency>
            <groupId>com.sun.xml.bind</groupId>
            <artifactId>jaxb-core</artifactId>
            <version>2.2.11</version>
        </dependency>
        <dependency>
            <groupId>com.sun.xml.bind</groupId>
            <artifactId>jaxb-impl</artifactId>
            <version>2.2.11</version>
        </dependency>
        <dependency>
            <groupId>javax.activation</groupId>
            <artifactId>activation</artifactId>
            <version>1.1.1</version>
        </dependency>
    </dependencies>

    <!-- Spring Cloud dependencies -->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Finchley.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
        <testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>org.jetbrains.kotlin</groupId>
                <artifactId>kotlin-maven-plugin</artifactId>
                <configuration>
                    <args>
                        <arg>-Xjsr305=strict</arg>
                    </args>
                    <compilerPlugins>
                        <plugin>spring</plugin>
                    </compilerPlugins>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>org.jetbrains.kotlin</groupId>
                        <artifactId>kotlin-maven-allopen</artifactId>
                        <version>${kotlin.version}</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>
    </build>

</project>

My application.properties:

server.port=8761
spring.application.name=eureka-server
eureka.instance.hostname=localhost
eureka.server.maxThreadsForPeerReplication=0
eureka.client.registerWithEureka=false
eureka.client.fetchRegistry=false

I ended up not using spring-cloud-starter-netflix-eureka-server as a dependency, and instead opted for the (deprecated) spring-cloud-starter-eureka-server. Eureka is accessible from localhost:8761.