微服务学习之路–Springcloud之zuul网关

一.什么是zuul网关

zuul 是netflix开源的一个API Gateway 服务器,Zuul 相当于是设备和 Netflix 流应用的 Web 网站后端所有请求的前门。Zuul 可以适当的对多个 Amazon Auto Scaling Groups 进行路由请求。
按我的理解,他就是一系列的filters,web应用

zuul网关的作用

Zuul 包含多个组件：

zuul-core
zuul-simple-webapp
zuul-netflix
zuul-netflix-webapp

Zuul提供了动态路由、弹性负载、监控和安全等功能,对接口请求进行鉴权、登录判断等操作.

代码简单实现

1.创建项目

2.依赖包

        <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>

3.自定义路由规则

zuul:
#  自定义路由
  routes:
    order-service: /gateway/order/**
    product-service: /gateway/product/**
#    过滤路由
  ignored-services: /*-service/**
# 设置 Http请求头过滤 为空
  sensitive-headers:

4 .访问接口

http://localhost:9000/gateway/order/api/v1/order/save?userId=123&productId=1

http://localhost:网关端口/网关配置的目标服务的路由/**

5.创建filter类-loginFilter


/**
 * @description: 过滤器
 * @author: ※狗尾巴草
 * @date: 2020-10-16 21:54
 **/
@Component
public class loginFilter extends ZuulFilter {

    /**
    * @description: 过滤类型
    * @params:
    * @author: 狗尾巴草
    * @time:
    */
    @Override
    public String filterType() {
        return PRE_TYPE;
    }

    /**
    * @description: 过滤器的顺序,越小越先执行
    * @params:
    * @author: 狗尾巴草
    * @time:
    */
    @Override
    public int filterOrder() {
        return 4;
    }

    /**
    * @description: 拦截是否生效
    * @params:
    * @author: 狗尾巴草
    * @time:
    */
    @Override
    public boolean shouldFilter() {
        HttpServletRequest request = RequestContext.getCurrentContext().getRequest();
        String regEx  = ".*/gateway/order/.*";
        Pattern pattern = Pattern.compile(regEx,Pattern.CASE_INSENSITIVE);
        Matcher matcher = pattern.matcher(request.getRequestURI());
        if(matcher.find()){ //被拦截
            return true;
        }
        return false;
    }

    /**
    * @description: 业务逻辑
    * @params:
    * @author: 狗尾巴草
    * @time:
    */
    @Override
    public Object run() throws ZuulException {
        System.out.println("拦截了");

        return null;
    }
}

6.访问接口

http://localhost:9000/gateway/order/api/v1/order/save?userId=123&productId=1&token=123

7.添加返回JSON数据

修改拦截的业务逻辑方法


    /**
    * @description: 业务逻辑
    * @params:
    * @author: 狗尾巴草
    * @time:
    */
    @Override
    public Object run() throws ZuulException {
        System.out.println("拦截了");
        RequestContext requestContext= RequestContext.getCurrentContext();
        HttpServletRequest request = requestContext.getRequest();
        requestContext.getResponse().setContentType(MediaType.APPLICATION_JSON_UTF8_VALUE); //设置编码
        requestContext.getResponse().setCharacterEncoding("UTF-8");
        String token = request.getHeader("token");
        if(StringUtils.isBlank(token)){
            token=request.getParameter("token");
        }
        JSONObject object = new JSONObject();
        //判断token有效性
        if(StringUtils.isBlank(token)){
            object.put("status","401");
            requestContext.setSendZuulResponse(false); // 不再向下执行
            requestContext.setResponseBody(object.toString());
            requestContext.setResponseStatusCode(HttpStatus.INTERNAL_SERVER_ERROR.value()); //设置http状态码
        }
        return null;
    }