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本文利用spring cloud集成消息服务，建立消息生产者与消息消费者，与消息服务器通信

首先需要搭建rabbit消息服务器，这里作为测试，利用在线服务https://www.cloudamqp.com

然后建立消息生产者微服务cloud-stream-producer-rabbitmq

消息生产者微服务需要引入依赖spring-cloud-stream、spring-cloud-stream-binder-rabbit，其pom.xml文件如下；

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>cloud-stream-producer-rabbitmq</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>cloud-stream-producer-rabbitmq</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-binder-rabbit</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-rabbit-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-test-support</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>

</project>

User消息类

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package com.ralab.cloudstreamproducerrabbitmq;

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;

@JsonIgnoreProperties(ignoreUnknown = true)
public class User {
    private String userName;
    private String addr;
    private int age;

    public User(){}
    public User(String userName, String addr, int age) {
        this.userName = userName;
        this.addr = addr;
        this.age = age;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getAddr() {
        return addr;
    }

    public void setAddr(String addr) {
        this.addr = addr;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

ProducerController3消息生产类

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package com.ralab.cloudstreamproducerrabbitmq;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.messaging.Source;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.support.MessageBuilder;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
@EnableBinding(Source.class)
public class ProducerController3 {

    @Autowired
    @Qualifier(Source.OUTPUT)
    private MessageChannel userChannel;

    @PostMapping("/produce")
    public void publish3(@RequestBody User user) {

        Message<User> msg = MessageBuilder.withPayload(user).build();
        this.userChannel.send(msg);
        //this.binding.greeting().send(msg);
    }
}

application.properties配置

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spring.rabbitmq.addresses=amqp://byqzaxwz:Tlrt32CSQYMHEeitFVUB43wkCSsiUlwo@hornet.rmq.cloudamqp.com/byqzaxwz
spring.cloud.stream.bindings.output.destination = user

server.port=8080

运行该应用CloudStreamProducerRabbitmqApplication

同时建立消息消费者微服务cloud-stream-consumer-rabbitmq，其pom.xml文件如下：

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>cloud-stream-consumer-rabbitmq</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>cloud-stream-consumer-rabbitmq</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-binder-rabbit</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-rabbit-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-test-support</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>

</project>

同样需要添加User消息类，与消息生产者微服务相同
添加消息消费类UserListener

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package com.ralab.cloudstreamconsumerrabbitmq;

import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.annotation.StreamListener;
import org.springframework.cloud.stream.messaging.Sink;


@EnableBinding(Sink.class)
public class UserListener {

    @StreamListener(target = Sink.INPUT)
    public void processUserChannelGreeting(User user) {
        System.out.println(user.getUserName()+":"+user.getAddr()+":"+user.getAge());
    }
}

application.properties配置

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spring.rabbitmq.addresses=amqp://byqzaxwz:Tlrt32CSQYMHEeitFVUB43wkCSsiUlwo@hornet.rmq.cloudamqp.com/byqzaxwz
spring.cloud.stream.bindings.input.destination = user
server.port=9090

运行CloudStreamConsumerRabbitmqApplication
查看rabbitmq消息服务器

测试发送消息

然后就可以看到在消息消费者微服务的控制台输出消息

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上文中的被监控端微服务，我们引入了spring-boot-admin-starter-client依赖，这样一来，貌似对我们的微服务有某种侵入性；在实际应用中，我们的微服务都是注册到eureka server服务器，因此监控服务端spring-boot-admin可以从注册服务器获取我们的微服务列表，而不用每一个监控端微服务都引入监控服务端的url信息，也不用引入spring-boot-admin-starter-client依赖（当然需要引入spring-boot-starter-actuator依赖）

改造微服务ralab-admin

  • Add the Maven spring-cloud-starter-netflix-eureka-client denpendencys
  • Add @EnableEurekaClient to the application class
  • Config eureka server info to application.yml file
    其pom.xml文件如下：
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    <?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>2.1.8.RELEASE</version>
            <relativePath/> <!-- lookup parent from repository -->
        </parent>
        <groupId>com.ralab</groupId>
        <artifactId>ralab-admin</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>ralab-admin</name>
        <description>Demo project for Spring Boot</description>

        <properties>
            <java.version>1.8</java.version>
            <spring-boot-admin.version>2.1.5</spring-boot-admin.version>
            <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
        </properties>

        <dependencies>
            <dependency>
                <groupId>de.codecentric</groupId>
                <artifactId>spring-boot-admin-starter-server</artifactId>
            </dependency>

            <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-test</artifactId>
                <scope>test</scope>
            </dependency>
        </dependencies>

        <dependencyManagement>
            <dependencies>
                <dependency>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-dependencies</artifactId>
                    <version>${spring-cloud.version}</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
                <dependency>
                    <groupId>de.codecentric</groupId>
                    <artifactId>spring-boot-admin-dependencies</artifactId>
                    <version>${spring-boot-admin.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>

    </project>

RalabAdminApplication文件

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package com.ralab.ralabadmin;

import de.codecentric.boot.admin.server.config.EnableAdminServer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

@SpringBootApplication
@EnableAdminServer
@EnableEurekaClient
public class RalabAdminApplication {

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

}

application.yml文件

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server:
  port: 8080
spring:
  application:
    name: service-admin

eureka:
  instance:
    # ip-address: 127.0.0.1
    prefer-ip-address: true # 补充
    instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${server.port}
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/

然后运行eureka server服务器,运行被监控微服务，运行上面的监控微服务,打开http://127.0.0.1:8080

记得被监控的微服务加入依赖

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

添加配置

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management:
  endpoints:
    web:
      exposure:
        include: '*'
  endpoint:
    health:
      show-details: always

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在前面的文章中，我们涉及到了Spring Boot Actuator组件，该组件用来监控系统运行状态，不过，貌似该组件显示的信息是以文本的形式展示的，对于我们查看不太方便，为此spring cloud提供了一个更强大的监控组件Spring Boot Admin，以可视化的形式显示监控状态
微服务ralab-admin

  • New microservice ‘ralab-admin’ and and add the Maven spring-boot-admin-starter-server denpendencys
  • Add @EnableAdminServer to the application class
  • Config Spring Boot Admin info to application.yml file
    其pom.xml文件如下：
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    <?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>2.1.8.RELEASE</version>
            <relativePath/> <!-- lookup parent from repository -->
        </parent>
        <groupId>com.ralab</groupId>
        <artifactId>ralab-admin</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>ralab-admin</name>
        <description>Demo project for Spring Boot</description>

        <properties>
            <java.version>1.8</java.version>
            <spring-boot-admin.version>2.1.5</spring-boot-admin.version>
        </properties>

        <dependencies>
            <dependency>
                <groupId>de.codecentric</groupId>
                <artifactId>spring-boot-admin-starter-server</artifactId>
            </dependency>

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

        <dependencyManagement>
            <dependencies>
                <dependency>
                    <groupId>de.codecentric</groupId>
                    <artifactId>spring-boot-admin-dependencies</artifactId>
                    <version>${spring-boot-admin.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>

    </project>

RalabAdminApplication文件

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package com.ralab.ralabadmin;

import de.codecentric.boot.admin.server.config.EnableAdminServer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@EnableAdminServer
public class RalabAdminApplication {

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

}

application.yml

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server:
  port: 8080
spring:
  application:
    name: service-admin

运行RalabAdminApplication，打开http://127.0.0.1:8080
然后我们新建被监控端微服务，引入spring-boot-admin-client依赖，其pom.xml文件如下：

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo2</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo2</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-boot-admin.version>2.1.5</spring-boot-admin.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>de.codecentric</groupId>
            <artifactId>spring-boot-admin-starter-client</artifactId>
        </dependency>


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

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>de.codecentric</groupId>
                <artifactId>spring-boot-admin-dependencies</artifactId>
                <version>${spring-boot-admin.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>

</project>

application.yml配置

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server:
  port: 8091
spring:
  application:
    name: web_a
  boot:
    admin:
      client:
        instance:
          prefer-ip: true
        url: http://127.0.0.1:8080  #配置需要接入的admin-server地址

management:
  endpoints:
    web:
      exposure:
        include: "*"
  endpoint:
    health:
      show-details: always

运行Demo2Application，这时我们可以看到监控状态信息http://127.0.0.1:8080

|

上文中利用zuul组件实现了微服务的路由功能，本文继续探讨其过滤器、熔断器功能
zuul过滤器分不同类型，具体有error、post、pre、route过滤器，貌似zuul组件内置实现了一些默认的过滤器

本文参考网上的文章，实现pre过滤器
MyPreFilter实现ZuulFilter接口

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package com.ralab.ralabzuul.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;
import org.springframework.stereotype.Component;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Component
public class MyPreFilter extends ZuulFilter {

    private static final Logger logger= LoggerFactory.getLogger(MyPreFilter.class);
    @Override
    public String filterType() {
        return FilterConstants.PRE_TYPE;
    }

    @Override
    public int filterOrder() {
        return 0;
    }

    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() throws ZuulException {

        RequestContext requestContext = RequestContext.getCurrentContext();        
        HttpServletRequest request = requestContext.getRequest();        

        //获取请求参数
        String token = request.getParameter("token");

        //校验token是否可以通过
        if (StringUtils.isNotBlank(token) && token.equals("maomao")) {
            requestContext.setSendZuulResponse(true);
            requestContext.setResponseStatusCode(200);
            requestContext.set("code", 1);
        } else {
            requestContext.setSendZuulResponse(false);
            requestContext.setResponseStatusCode(401);
            HttpServletResponse response = requestContext.getResponse();
            response.setHeader("content-type", "text/html;charset=utf-8");
            requestContext.setResponseBody("网关认证失败，停止路由");
            requestContext.set("code", 0);
        }

        return null;
    }
}

测试http://127.0.0.1:8040/api/nlpservice/nlp/api

接下来实现fallback机制，MyFallbackProvider实现FallbackProvider接口

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package com.ralab.ralabzuul.filter;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.netflix.zuul.filters.route.FallbackProvider;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;

@Component
public class MyFallbackProvider implements FallbackProvider {


    private final Logger logger = LoggerFactory.getLogger(FallbackProvider.class);

    @Override
    public String getRoute() {
        return "*";
    }

    @Override
    public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
        if (cause != null && cause.getCause() != null) {
            String reason = cause.getCause().getMessage();
            logger.info("Excption {}",reason);
        }
        return fallbackResponse();
    }

    public ClientHttpResponse fallbackResponse() {
        return new ClientHttpResponse() {
            @Override
            public HttpStatus getStatusCode() throws IOException {
                return HttpStatus.OK;
            }

            @Override
            public int getRawStatusCode() throws IOException {
                return 200;
            }

            @Override
            public String getStatusText() throws IOException {
                return "OK";
            }

            @Override
            public void close() {

            }

            @Override
            public InputStream getBody() throws IOException {
                return new ByteArrayInputStream("当前服务貌似不可用 The service is unavailable.".getBytes());
            }

            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders headers = new HttpHeaders();
                headers.setContentType(MediaType.APPLICATION_JSON);
                return headers;
            }
        };
    }
}

停止微服务ralab-nlp，测试http://127.0.0.1:8040/api/nlpservice/nlp/api?token=maomao

|

本文新建网关（gateway）微服务，利用网关实现路由映射以及过滤器、熔断器等功能
微服务’ralab-zuul’

  • New microservice ‘ralab-zuul’ and add the Maven pring-cloud-starter-netflix-zuul denpendencys
  • Config eureka server info to application.yml file
  • Add @EnableZuulProxy to the application class

其pom.xml文件如下：

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>ralab-zuul</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>ralab-zuul</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <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-netflix-zuul</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>

</project>

配置application.yml

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server:
  port: 8040
spring:
  application:
    name: microservice-gateway-zuul
eureka:
  instance:
    # ip-address: 127.0.0.1
    prefer-ip-address: true # 补充
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

management:
  endpoints:
    web:
      exposure:
        include: '*'
  endpoint:
    health:
      show-details: always

RalabZuulApplication文件

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package com.ralab.ralabzuul;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;

//@EnableEurekaClient
@SpringBootApplication
@EnableZuulProxy
public class RalabZuulApplication {

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

}

运行RalabZuulApplication，打开http://127.0.0.1:8040/actuator/routes，显示网关默认的路由

测试打开http://127.0.0.1:8040/nlp-service/nlp/api，路由成功

我们可以自定义路由规则，配置如下

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server:
  port: 8040
spring:
  application:
    name: microservice-gateway-zuul
eureka:
  instance:
    # ip-address: 127.0.0.1
    prefer-ip-address: true # 补充
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

management:
  endpoints:
    web:
      exposure:
        include: '*'
  endpoint:
    health:
      show-details: always

zuul:
  ignored-services: '*'
  prefix: /api
  routes:
    nlp-service: /nlpservice/**

打开http://127.0.0.1:8040/actuator/routes

测试打开http://127.0.0.1:8040/nlp-service/nlp/api

|

配置服务器ralab-configserver同样作为微服务，可以注册到注册服务器ralab-server，然后其他微服务通过注册服务器获取到配置服务器的相关配置信息

我们先改造配置服务器ralab-configserver

  • Add the Maven spring-cloud-starter-netflix-eureka-client denpendency
  • Add ralab-server info to applcation.yml file

其pom.xml文件如下:

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>ralab-configserver</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>ralab-configserver</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-server</artifactId>
        </dependency>
        <!--添加依赖，注册到eureka-server-->
        <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-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>

</project>

application.yml

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server:
  port: 8888
spring:
  cloud:
    config:
      server:
        encrypt.enabled: false
        git:
          uri: https://github.com/chenying99/config-repo
          searchPaths: licensingservice,organizationservice

eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

重新运行RalabConfigserverApplication，浏览器打开http://localhost:8761/

然后我们改造微服务ralab-client
bootstrap.yml文件

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eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/

server:
  port: 8091
management:
  endpoints:
    web:
      exposure:
        include: hystrix.stream

spring:
  application:
    name: nlp-client
  cloud:
    config:
      name: licensingservice  # 配置应用名
      profile: default
      label: master
      discovery:
        enabled: true
        service-id: configserver # 配置服务器注册名

重新运行RalabClientApplication，打开http://localhost:8091/nlp/config

|

上文我们已经构建了配置服务器ralab-configserver，那么我们的微服务怎样从该配置服务器获取相关配置信息呢？这里我们改造原来的ralab-client微服务

ralab-client微服务

  • Add the Maven spring-cloud-starter-config denpendency
  • Test example.property value in NlpResource
  • Add configserver info to bootstrap.yml file

其pom.xml文件添加spring-cloud-starter-config依赖

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>ralab-client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>ralab-client</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR2</spring-cloud.version>
    </properties>

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

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--添加依赖，获取配置服务器的相关配置信息-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</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>

</project>

NlpResource文件

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package com.ralab.ralabclient.resources;

import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
@RequestMapping("/nlp")
@RefreshScope
public class NlpResource {

    @Autowired
    private RestTemplate restTemplate;

    @Value("${example.property}")
    private String exampleProperty;

    @RequestMapping("/config")
    public String home() {
        return "exampleProperty:" + exampleProperty;
    }

    @GetMapping("/service")
    @HystrixCommand(fallbackMethod = "getFallbackIndex")
    public String index()
    {
      //String result = restTemplate.getForObject("http://localhost:8090/nlp/api", String.class);
      String result = restTemplate.getForObject("http://nlp-service/nlp/api", String.class);
      return result;
    }

    private String getFallbackIndex()
    {
        //String result = restTemplate.getForObject("http://localhost:8090/nlp/api", String.class);

        return "不好意思，没有获取到服务端信息";
    }
}

bootstrap.yml

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eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/

server:
  port: 8091
management:
  endpoints:
    web:
      exposure:
        include: hystrix.stream

spring:
  application:
    name: nlp-client
  cloud:
    config:
      uri: http://localhost:8888
      name: licensingservice
      profile: default
      label: master

运行RalabClientApplication，打开http://localhost:8091/nlp/config

补充：如果配置服务器的配置信息作了修改，这时我们的微服务配置客户端可以主动拉取（pull）
在获取配置属性的类上加注解，@RefreshScope，然后发送post请求http://127.0.0.1:8091/actuator/refresh

|

在spring cloud建构的微服务架构中，多个微服务有时需要统一配置信息，这时我们可以建立配置服务器ralab-configserver，然后各微服务从该配置服务器获取配置信息

ralab-configserver服务器

  • New microservice ‘ralab-configserver’ and add the Maven spring-cloud-config-server denpendency
  • Add @EnableConfigServer to the application class
  • Add github repository url to application.yml file

配置服务器的pom.xml文件如下：

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>ralab-configserver</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>ralab-configserver</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-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>

</project>

RalabConfigserverApplication文件

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package com.ralab.ralabconfigserver;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.config.server.EnableConfigServer;

@SpringBootApplication
@EnableConfigServer
public class RalabConfigserverApplication {

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

}

bootstrap.yml

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spring:
  application:
    name: configserver

application.yml

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server:
  port: 8888
spring:
  cloud:
    config:
      server:
        encrypt.enabled: false
        git:
          uri: https://github.com/chenying99/config-repo
          searchPaths: licensingservice,organizationservice

运行RalabConfigserverApplication，然后打开http://localhost:8888/licensingservice/default

|

前面的文章，我们利用RestTemplate对象和feign组件实现了微服务之间的通信，并且通过集成Hystrix，从而实现了容错及故障恢复功能

本文主要实现对Hystrix的可视化监控

这里新建微服务’ralab-hystrix-dashboard’

  • New microsevice ralab-hystrix-dashboard and add the Maven spring-cloud-starter-netflix-hystrix-dashboard denpendency
  • Add @EnableHystrixDashboard to the application class
  • Config info to application.yml file

同时被监控的微服务

  • Add spring-boot-starter-actuator denpendency
  • Add management.endpoints.web.exposure.include=hystrix.stream parameter to the application file

微服务’ralab-hystrix-dashboard’pom.xml文件如下：

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<?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>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ralab</groupId>
    <artifactId>ralab-hystrix-dashboard</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>ralab-hystrix-dashboard</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</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>

</project>

RalabHystrixDashboardApplication文件

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package com.ralab.ralabhystrixdashboard;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.hystrix.dashboard.EnableHystrixDashboard;

@SpringBootApplication
@EnableHystrixDashboard
public class RalabHystrixDashboardApplication {

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

}

application.yml文件

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spring:
  application:
    name: hystrix-dashboard
server:
  port: 8080

运行RalabHystrixDashboardApplication，打开http://localhost:8080/hystrix

同时被监控的微服务加入依赖

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

曝露hystrix端点

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spring.application.name=nlp-client
server.port=8091
management.endpoints.web.exposure.include=hystrix.stream

这时在输入框输入’http://localhost:8091/actuator/hystrix.stream'，点击Monitor stream按钮，就可以看到如下页面了

注：spring cloud还提供了turbine组件对多个微服务的Hystrix信息进行聚合，从而实现对微服务cluster的Hystrix信息的可视化监控

|

上文我们采用feign组件与微服务’ralab-nlp’进行通信，在实际应用中，feign组件通过集成Hystrix，从而实现熔断机制
改造微服务’ralab-client’

  • Add the Maven spring-cloud-starter-netflix-hystrix denpendency
  • Config hystrix info to bootstrap.yml file
  • Add FeignClient fallback class by Implement EurekaFeignService Interface
    我们在前面的文章中已经添加了spring-cloud-starter-netflix-hystrix依赖
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    <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
            </dependency>

bootstrap.yml

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eureka:
  instance:
    # ip-address: 127.0.0.1
    prefer-ip-address: true # 补充
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/

server:
  port: 8091
management:
  endpoints:
    web:
      exposure:
        include: hystrix.stream

spring:
  application:
    name: nlp-client
  cloud:
    config:
      name: licensingservice
      profile: default
      label: master
      discovery:
        enabled: true
        service-id: configserver

feign:
  hystrix:
    enabled: true

EurekaFeignService文件

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package com.ralab.ralabclient.services;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RequestMapping;

@FeignClient(value = "nlp-service",fallback = EurekaFeignServiceFailure.class)
public interface EurekaFeignService {

    @RequestMapping(value = "nlp/api")
    String nlpService();
}

@Component
class EurekaFeignServiceFailure implements EurekaFeignService {
    @Override
    public String nlpService() {
        return "不好意思，feingn调用失败";
    }
}

NlpResource文件 注释@HystrixCommand注解

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package com.ralab.ralabclient.resources;

import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.ralab.ralabclient.services.EurekaFeignService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
@RequestMapping("/nlp")
@RefreshScope
public class NlpResource {

    @Autowired
    private RestTemplate restTemplate;

    @Autowired
    private EurekaFeignService eurekaFeignService;

    @Value("${example.property}")
    private String exampleProperty;

    @RequestMapping("/config")
    public String home() {
        return "exampleProperty:" + exampleProperty;
    }

    @GetMapping("/service")
    @HystrixCommand(fallbackMethod = "getFallbackIndex")
    public String index()
    {
      //String result = restTemplate.getForObject("http://localhost:8090/nlp/api", String.class);
      String result = restTemplate.getForObject("http://nlp-service/nlp/api", String.class);
      return result;
    }

    @GetMapping("/feign")
    //@HystrixCommand(fallbackMethod = "getFallbackIndex")
    public String feignservice()
    {
        //String result = restTemplate.getForObject("http://localhost:8090/nlp/api", String.class);
        String result = eurekaFeignService.nlpService();
        return result;
    }

    private String getFallbackIndex()
    {
        //String result = restTemplate.getForObject("http://localhost:8090/nlp/api", String.class);

        return "不好意思，没有获取到服务端信息";
    }
}

这时停止微服务’ralab-nlp’，打开http://localhost:8091/nlp/feign