SpringCloud Zuul自定义filter代码实例

<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.company</groupId>
  <artifactId>zuuldemo</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>zuuldemo</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
  </properties>
  <parent>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-parent</artifactId>
    <version>Edgware.RELEASE</version>
    <relativePath></relativePath>
  </parent>
  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-zuul</artifactId>
    </dependency>
    <dependency>
      <groupId>commons-codec</groupId>
      <artifactId>commons-codec</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.httpcomponents</groupId>
      <artifactId>httpclient</artifactId>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>com.google.guava</groupId>
      <artifactId>guava</artifactId>
    </dependency>
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.58</version>
    </dependency>
  </dependencies>
</project>

server:
  port: 80
spring:
  application:
   name: api-geteway
  http:
   multipart:
     enabled: true # 使用http multipart上传处理
     file-size-threshold: 1MB # 当上传文件达到1MB的时候进行磁盘写入
     max-request-size: 10MB # 设置最大的请求文件的大小
     max-file-size: 10MB # 设置单个文件的最大长度
zuul:
  routes:
   weixin:
     path: /mypath/**
     url: https://www.baidu.com

package com.company.zuuldemo;

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

import com.company.zuuldemo.filter.MyFilter;

/**
 * Hello world!
 *
 */
@EnableZuulProxy
@SpringBootApplication
public class ZuulApp {

  //使用filter
  @Bean
  public MyFilter myFilter() {
    return new MyFilter();
  }

//  @Bean
//  public FirstFilter firstFilter() {
//    return new FirstFilter();
//  }
//
//  @Bean
//  public SecondFilter secondFilter() {
//    return new SecondFilter();
//  }

  public static void main(String[] args) {
    // System.out.println( "Hello World!" );
    SpringApplication.run(ZuulApp.class);
  }
}

package com.company.zuuldemo.filter;

import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;

public class MyFilter extends ZuulFilter {

  final static Logger logger = LoggerFactory.getLogger(FirstFilter.class);

  // 这里可以依据url规则判断是否需要进行过滤 true需要过滤进入run方法 ,false直接忽略
  public boolean shouldFilter() {
    RequestContext ctx = RequestContext.getCurrentContext();
    logger.info(ctx.getRequest().getRequestURI() + " get request path info");
    String url = ctx.getRequest().getRequestURI().toLowerCase();

    // 这里判断url逻辑
    if (url.startsWith("/login")) {
      return false;
    }

    return true;
  }

  public Object run() {

    RequestContext ctx = RequestContext.getCurrentContext();

    // 通过其它业务生成token
    String access_token = "user_name_token";

    // 使用1 ：向request的header中增加参数access_token
    ctx.addZuulRequestHeader("access_token", access_token);

    // 使用2：向request的url里增加参数,示例增加 access_token
    Map<String, List<String>> requestQueryParams = ctx.getRequestQueryParams();
    if (requestQueryParams == null) {
      requestQueryParams = new HashMap<>();
    }

    requestQueryParams.put("access_token", Arrays.asList(access_token));

    ctx.setRequestQueryParams(requestQueryParams);

    //使用3 ：:判断是否登录,如果未登录直接返回404
    if (access_token == null || access_token.trim().length() == 0) {
      //过滤该请求，不对其进行路由(直接输入返回）
      ctx.setSendZuulResponse(false);
      //返回错误码
      ctx.setResponseStatusCode(401);
      // 返回错误内容
      ctx.setResponseBody("{\"result\":\"access_token is not correct!\"}");
      
      //让下一个Filter看到上一个Filter的状态用于过滤器间的协调
      ctx.set("my_filter_is_success", false);
      return null; 
    }

    // 对该请求进行路由(默认就是true)
    //ctx.setSendZuulResponse(true);
    //ctx.setResponseStatusCode(200);
    //让下一个Filter看到上一个Filter的状态用于过滤器间的协调
    ctx.set("my_filter_is_success", false);

    return null; //直接返回null即可
  }

  @Override
  public String filterType() {
    // 前置过滤器
    //pre：可以在请求被路由之前调用
    //route：在路由请求时候被调用
    //post：在route和error过滤器之后被调用
    //error：处理请求时发生错误时被调用
    return "pre";
  }

  @Override
  public int filterOrder() {
    //优先级为0，数字越大，优先级越低 
    return 0;
  }
}