SpringCloud-使用路由网关统一访问接口(附代码下载)

Myth丶恋晨 2023-10-11 13:51 20阅读 0赞

## 场景 ##

SpringCloud-使用熔断器仪表盘监控熔断：

[https://blog.csdn.net/BADAO\_LIUMANG\_QIZHI/article/details/102673599][https_blog.csdn.net_BADAO_LIUMANG_QIZHI_article_details_102673599]

SpringCloud -创建统一的依赖管理：

[https://blog.csdn.net/BADAO\_LIUMANG\_QIZHI/article/details/102530574][https_blog.csdn.net_BADAO_LIUMANG_QIZHI_article_details_102530574]

上面在实现了使用熔断仪表盘进行监控熔断后，使用路由网关统一访问接口。

### API网关 ###

API网关负责请求路由、组合和协议转发。所有的客户端请求首先要通过API网关，之后请求被路由到适当的服务。

API网关通常会调用多个微服务和聚合结果来处理一个请求。它可以在Web协议(如HTTP和WebSocket)和利用于内部的非Web友好协议之间进行转换。

### 负载均衡方式 ###

在Spring Cloud微服务系统中，一种常见的负载均衡方式是：客户端的请求先经过负载均衡(Zuul、Nginx),再到达服务网关(Zuul集群)，然后再到具体的服务。服务统一注册到高可用的服务注册中心集群，服务的所有的配置文件放在Git仓库，方便开发人员随时改配置。

### Zuul简介 ###

Zuul的主要功能是路由转发和过滤器。路由功能是微服务的一部分。

Zuul默认和Ribbon结合实现了负载均衡的功能。

注：

博客：  
[https://blog.csdn.net/badao\_liumang\_qizhi][https_blog.csdn.net_badao_liumang_qizhi]  
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## 实现 ##

参考上面构建项目的方式，依次建立目录hello-spring-cloud-zuul目录以及在

目录下新建pom.xml，并将其托管。然后新建src/main/java目录和src/main/resources目录并分别进行目录设置。

然后在java下新建包，包下新建启动类，在resources下新建配置文件application.yml。

完成后的目录为：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70][]

pom.xml代码

<?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>com.badao</groupId>
            <artifactId>hello-spring-cloud-dependencies</artifactId>
            <version>1.0.0-SNAPSHOT</version>
            <relativePath>../hello-spring-cloud-dependencies/pom.xml</relativePath>
        </parent>
    
        <artifactId>hello-spring-cloud-zuul</artifactId>
        <packaging>jar</packaging>
    
        <name>hello-spring-cloud-zuul</name>
        <url>https://blog.csdn.net/badao_liumang_qizhi</url>
        <inceptionYear>2019-Now</inceptionYear>
    
        <dependencies>
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-tomcat</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </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-netflix-zuul</artifactId>
            </dependency>
            
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <configuration>
                        <mainClass>com.badao.hello.spring.cloud.zuul.ZuulApplication</mainClass>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </project>

配置文件application.yml代码

spring:
      application:
        name: hello-spring-cloud-zuul
    
    server:
      port: 8769
    
    eureka:
      client:
        serviceUrl:
          defaultZone: http://localhost:8761/eureka/
    
    zuul:
      routes:
        api-a:
          path: /api/a/**
          serviceId: hello-spring-cloud-web-admin-ribbon
        api-b:
          path: /api/b/**
          serviceId: hello-spring-cloud-web-admin-feign

注：

以 /api/a 开头的请求都转发给 hello-spring-cloud-web-admin-ribbon 服务  
以 /api/b 开头的请求都转发给 hello-spring-cloud-web-admin-feign 服务

其中routes是固定的，但是api-a与api-b是自己定义的。

在自定义的路由中，path代表请求的路径，serviceId代表真正映射的服务的Id。

在path中\*\*代表通配符，即以/api/a开头的都会请求同组内的serviceId所对应的服务。

然后在包下新建com.badao.hello.spring.cloud.zuul包，并在包下新建ZuulApplication启动类

package com.badao.hello.spring.cloud.zuul;
    
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
    import org.springframework.cloud.netflix.zuul.EnableZuulProxy;
    
    
    @SpringBootApplication
    @EnableEurekaClient
    @EnableZuulProxy
    public class ZuulApplication {
        public static void main(String[] args) {
            SpringApplication.run(ZuulApplication.class, args);
        }
    }

至此整个服务体系的结构如下

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 1][]

### 效果 ###

我们依次启动Eureka服务、服务提供者、两个服务消费者、zuul的Application启动类

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 2][]

然后打开浏览器，输入：

[http://localhost:8761/][http_localhost_8761]

打开Eureka的服务与注册发现中心，发现全部被注册并发现

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 3][]

然后再打开浏览器输入：

[http://localhost:8769/api/a/hi?message=HelloZuulFromBadao][http_localhost_8769_api_a_hi_message_HelloZuulFromBadao]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 4][]

再打开浏览器输入：

[http://localhost:8769/api/b/hi?message=HelloZuulFromBadao][http_localhost_8769_api_b_hi_message_HelloZuulFromBadao]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 5][]

则Zuul的路由配置功能配置成功。

### 配置网关路由失败时的回调 ###

有时如果因为网络、内存等原因导致网关路由失败，则需要配置失败时的回调。

再新建fallback包，包下新建WebAdminFeignFallbackProvider

package com.badao.hello.spring.cloud.zuul.fallback;
    
    import com.fasterxml.jackson.databind.ObjectMapper;
    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;
    import java.util.HashMap;
    import java.util.Map;
    @Component
    public class WebAdminFeignFallbackProvider implements FallbackProvider {
    
        @Override
        public String getRoute() {
            // ServiceId，如果需要所有调用都支持回退，则 return "*" 或 return null
            return "hello-spring-cloud-web-admin-feign";
        }
    
        /**
         * 如果请求服务失败，则返回指定的信息给调用者
         * @param route
         * @param cause
         * @return
         */
        @Override
        public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
            return new ClientHttpResponse() {
                /**
                 * 网关向 api 服务请求失败了，但是消费者客户端向网关发起的请求是成功的，
                 * 不应该把 api 的 404,500 等问题抛给客户端
                 * 网关和 api 服务集群对于客户端来说是黑盒
                 * @return
                 * @throws IOException
                 */
                @Override
                public HttpStatus getStatusCode() throws IOException {
                    return HttpStatus.OK;
                }
    
                @Override
                public int getRawStatusCode() throws IOException {
                    return HttpStatus.OK.value();
                }
    
                @Override
                public String getStatusText() throws IOException {
                    return HttpStatus.OK.getReasonPhrase();
                }
    
                @Override
                public void close() {
    
                }
    
                @Override
                public InputStream getBody() throws IOException {
                    ObjectMapper objectMapper = new ObjectMapper();
                    Map<String, Object> map = new HashMap<>();
                    map.put("status", 200);
                    map.put("message", "无法连接，请检查您的网络");
                    return new ByteArrayInputStream(objectMapper.writeValueAsString(map).getBytes("UTF-8"));
                }
    
                @Override
                public HttpHeaders getHeaders() {
                    HttpHeaders headers = new HttpHeaders();
                    // 和 getBody 中的内容编码一致
                    headers.setContentType(MediaType.APPLICATION_JSON_UTF8);
                    return headers;
                }
            };
        }
    }

### 代码下载 ###

[https://download.csdn.net/download/badao\_liumang\_qizhi/11908425][https_download.csdn.net_download_badao_liumang_qizhi_11908425]

[https_blog.csdn.net_BADAO_LIUMANG_QIZHI_article_details_102673599]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/102673599
[https_blog.csdn.net_BADAO_LIUMANG_QIZHI_article_details_102530574]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/102530574
[https_blog.csdn.net_badao_liumang_qizhi]: https://blog.csdn.net/badao_liumang_qizhi
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20191024215021569.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20191024215100911.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 2]: https://img-blog.csdnimg.cn/20191024215108187.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=,size_16,color_FFFFFF,t_70
[http_localhost_8761]: http://localhost:8761/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 3]: https://img-blog.csdnimg.cn/20191024215120914.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=,size_16,color_FFFFFF,t_70
[http_localhost_8769_api_a_hi_message_HelloZuulFromBadao]: http://localhost:8769/api/a/hi?message=HelloZuulFromBadao
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 4]: https://img-blog.csdnimg.cn/20191024215132225.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=,size_16,color_FFFFFF,t_70
[http_localhost_8769_api_b_hi_message_HelloZuulFromBadao]: http://localhost:8769/api/b/hi?message=HelloZuulFromBadao
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk_size_16_color_FFFFFF_t_70 5]: https://img-blog.csdnimg.cn/20191024215141870.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0JBREFPX0xJVU1BTkdfUUlaSEk=,size_16,color_FFFFFF,t_70
[https_download.csdn.net_download_badao_liumang_qizhi_11908425]: https://download.csdn.net/download/badao_liumang_qizhi/11908425