SpringCloud搭建微服务框架（三）- 网关Zuul

Zuul的主要功能是路由转发和过滤器，对外提供统一的访问入口，并且做路由转发，例如将/param的路由请求发到parameter-consumer服务，将/login的路由请求发到customer服务等。

Zuul网关作为微服务组件的一部分，相对于eureka server注册中心而言，是eureka client，同样需注册到注册中心
 

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-zuul</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>

完整的pom.xml文件如下：

<?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.example</groupId>
    <artifactId>zuul</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
 
    <name>zuul</name>
    <description>Demo project for Spring Boot</description>
 
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.2.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>
    </properties>
 
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web-services</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</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-zuul</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
    </dependencies>
 
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Dalston.RC1</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>

2.修改application.yml配置文件

server:
  port: 8791  #端口号
 
spring:
  application:
    name: zuul  #服务注册中心测试名
 
zuul:
  routes:
    api-a:
      path: /index/**
      serviceId: parameter-consumer  #如果是/index/**路径下的请求，则跳转到parameter-module
    api-b:
      path: /resource/**
      serviceId: parameter-consumer  #如果是/resource/**路径下的请求，则跳转到parameter-consumer
    api-c:
      path: /customer/**
      serviceId: parameter-consumer  #如果是/customer/**路径下的请求，则跳转到parameter-consumer
 
# 授权原生端点访问authentication
management:
  security:
    enabled: false
 
eureka:
  client:
    serviceUrl:
      defaultZone: http://127.0.0.1:8761/eureka/  #服务注册中心

注：关于授权原生端点访问授权，spring cloud提供了很多原生端点(如/info、/health、/env等，提供微服务框架的一些配置或运行时信息)，如下图，就是访问原生端点/health返回的信息：

以及启动时控制台的如下日志，显示的就是原生端点：

路由转发部分，有两点需要注意：

/index/** 和/index/* 以及/index/?的含义是不同的
若访问http://localhost:8791/index/aaa，请求被转发到parameter-consumer服务模块时，路由是/aaa，前面的/index会被截掉
路由配置规则（图片来源：https://blog.csdn.net/u012702547/article/details/78399406/）：

3.启动类添加注解@EnableZuulProxy启用网关和@EnableEurekaClient启用eureka client

package com.example.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
@EnableZuulProxy
@EnableEurekaClient
public class ZuulApplication {
 
    public static void main(String[] args) {
        SpringApplication.run(ZuulApplication.class, args);
    }
}

启动zuul网关应用程序，访问http://localhost:8761/，可以看到zuul网关已经被注册到注册中心：

访问网关http://localhost:8791/index/hello?name=world，可以看到确实转发了请求：