spring-cloud-gateway引入

spring-cloud-gateway引入总结（含修改响应body）

一、版本

pom.xml

<!-- 仅保留了spring系的版本 -->
<properties>
    <springframework.version>5.3.22</springframework.version>
    <spring-boot.version>2.3.12.RELEASE</spring-boot.version>
    <spring-cloud-netflix.version>2.2.9.RELEASE</spring-cloud-netflix.version>
    <spring-data.version>2.3.9.RELEASE</spring-data.version>
</properties>

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-gateway</artifactId>
    <version>2.2.9.RELEASE</version>
</dependency>
<dependency>
    <artifactId>spring-boot-starter-webflux</artifactId>
    <groupId>org.springframework.boot</groupId>
    <version>2.3.12.RELEASE</version>
</dependency>

二、配置文件

spring:
  application:
    name: gateway
  cloud:
    consul:
      host: *.*.*.*
      port: 8500
      discovery:
        service-name: ${spring.application.name}
        prefer-ip-address: true
        health-check-path: /health/check
        health-check-interval: 10s
        instance-id: ${spring.cloud.client.ip-address}:${server.port}
    gateway:
      discovery:
        locator:
          enabled: true
          lower-case-service-id: true
      httpclient:
        connect-timeout: 60

三、冲突问题

spring-cloud-gateway与spring-webmvc冲突，需剔除spring-webmvc，引入spring-webflux。需要替换javax.servlet.http.HttpServletRequest为org.springframework.http.server.reactive.ServerHttpRequest。获取header等的方法也要修改。

四、过滤器配置

对请求的token进行校验并对返参格式统一处理。

需注意对response的body修改，使用response.writeWith()方法即可，不必继承ServerHttpResponseDecorator等等方法。

GateWayPreFilter.java

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;

import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

import *.AuthService;
import java.util.List;

@Component
@Slf4j
public class GateWayPreFilter implements GlobalFilter, Ordered {

    /**
     * 排除过滤的 uri 地址
     */
    private static final String LOGIN_URI = "/login";
    private static final String HEALTH_CHECK_URI = "/health/check";

    @Autowired
    private AuthService authService;
    //判断是否需要过滤
    public boolean notFilter(ServerHttpRequest request) {
        //是否执行该过滤器
        // log.info("===当前请求路径为:" + request.getURI().toString());
        //注册和登录接口不拦截，其他接口都要拦截校验 token
        return request.getURI().getPath().contains(LOGIN_URI) || request.getURI().getPath().contains(HEALTH_CHECK_URI);
    }

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        ServerHttpRequest request = exchange.getRequest();
        if (notFilter(request)) {
            return chain.filter(exchange);
        }
        ServerHttpResponse response = exchange.getResponse();
        List<String> authorization = request.getHeaders().get("Authorization");
        String token = null;
        if (null != authorization) {
            token = authorization.stream().findFirst().orElse(null);
        }
        HttpHeaders headers = response.getHeaders();
        if (token == null || token.isEmpty()) {
            response.setStatusCode(HttpStatus.OK);
            //校验异常的返参格式处理，写入返参body
            String body = "{\"status\":-1,\"statusText\":\"没有token\"}";
            Flux<byte[]> flux = Flux.just(body.getBytes());
            Flux<DataBuffer> map = flux.map(bx -> response.bufferFactory().wrap(bx));
            headers.setContentType(MediaType.APPLICATION_JSON);
            return response.writeWith(map);

        }
        //2. 进行 权限认证的 逻辑
        boolean result = this.authenticate(token);
        if (result) {
            ////通过校验
            // 添加额外的请求参数为可选逻辑...
            List<String> param1s = request.getHeaders().get("param1");
            String param1 = null == userids ? null : param1s.stream().findFirst().orElse(null);
            //把头信息转发下去，并且放行
            ServerHttpRequest newRequest = request.mutate()
                .header("Authorization", token)
                .header("param1", param1).build();

            ServerWebExchange newExchange = exchange.mutate()
                .request(newRequest)
                .response(response).build();
            return chain.filter(newExchange);
        } else {
            //校验未通过
            //阻止请求。
            response.setStatusCode(HttpStatus.OK);
            String body = "{\"status\":-1,\"statusText\":\"用户登录超时，请重新登录\"}";
            Flux<byte[]> flux = Flux.just(body.getBytes());
            Flux<DataBuffer> map = flux.map(bx -> response.bufferFactory().wrap(bx));
            headers.setContentType(MediaType.APPLICATION_JSON);
            return response.writeWith(map);
        }
    }
    //token校验逻辑
    private boolean authenticate(String token) {
        return authService.authenticate(token);
    }

    @Override
    public int getOrder() {
        return -100;
    }
}

五、获取IP

RequestUtils.java

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.http.server.reactive.ServerHttpRequest;
import javax.servlet.http.HttpServletRequest;

@Slf4j
public class RequestUtil {

    public static String getIpAddr(HttpServletRequest request) {
        if(null == request){
            throw new ...;
        }
        String ip = null;
        try {
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getHeader("HTTP_X_FORWARDED_FOR");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getHeader("X-Forwarded-For");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getHeader("X-Real-IP");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getRemoteAddr();
            }
        } catch (Exception e) {
            log.error("RequestUtil.getIpAddr 获取请求真实ip 发生异常，异常信息为 - {} ", e);
            throw new ...;
        }
        return ip;
    }

    public static String getIpAddr(ServerHttpRequest request) {
        if(null == request){
            throw new ...;
        }
        String ip = null;
        try {
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getHeaders().getFirst("HTTP_X_FORWARDED_FOR");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getHeaders().getFirst("X-Forwarded-For");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getHeaders().getFirst("X-Real-IP");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip) || "localhost".equalsIgnoreCase(ip)) {
                ip = request.getRemoteAddress().getAddress().getHostAddress();
            }
        } catch (Exception e) {
            log.error("RequestUtil.getIpAddr 获取请求真实ip 发生异常，异常信息为 - {} ", e);
            throw new ...;
        }
        return ip;
    }
}

六、获取request对象

原项目中使用的是spring-webmvc，需要获取IP打点。之前使用RequestContextHolder.getRequestAttributes()获取，替换为spring-webflux后，报空指针异常。

提供简单的方法解决，在controller层的方法入参中增加org.springframework.http.server.reactive.ServerHttpRequest

    @PostMapping("/loginForOtherSys")
    public Map loginForOtherSys(@RequestBody @Valid LoginOtherSysUserVO loginOtherSysUserVO, ServerHttpRequest request) {
        ...
    }