react+spring 记录跨域问题的解决方法

react 跨域访问后台，默认是有跨域问题，并且火弧和谷歌浏览器，对跨域问题展示还不一样.

谷歌浏览器如下图：

此处状态是200，然而在response却没有任何信息，如下图

 

然而火弧浏览器，对该问题的描述，就清淅得多，

火弧浏览器告诉我们，跨域了，关于react跨域的帖子，网上也有相关帖子，搜索到的方法，大约都是如下解决方式：

如果你是通过creat-react-app构建的项目，请在package.json文件中的根目录下，添加"proxy": "http://api.xxxx.com"，如果你的项目，需要调用多个不同ip的接口，请使用如下配置：

"proxy": {
        "/api/roomapi": {
          "target": "http://open.douyucdn.cn",
          "changeorigin":true
        },
        "/api/v1":{
          "target":"http://capi.douyucdn.cn",
          "changeorigin":true
        }
      }

对于antd-pro的项目，需要在package.json的同等目录下添加.roadhogrc文件，具体代码如下:

    {
      "entry": "src/index.js",
      "extrababelplugins": [
        "transform-runtime",
        "transform-decorators-legacy",
        "transform-class-properties",
        ["import", { "libraryname": "antd", "librarydirectory": "es", "style": true }]
      ],
      "env": {
        "development": {
          "extrababelplugins": [
            "dva-hmr"
          ]
        }
      },
      "externals": {
        "g2": "g2",
        "g-cloud": "cloud",
        "g2-plugin-slider": "g2.plugin.slider"
      },
      "ignoremomentlocale": true,
      "theme": "./src/theme.js",
      "proxy": {
        "/api": {
          "target": "http://api.xxxx.com/",
          "changeorigin": true
        }
      }
    }

配置完成后，再次访问接口，还是出现一样的跨域问题，既然recat的配置，未解决跨域问题，我就把思路转到spring，在spring去处理跨域，在后端程序添加一个拦截器,

package com.gg.interceptor;

import java.util.arraylist;
import java.util.list;
import java.util.vector;

import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;

import org.springframework.web.servlet.handlerinterceptor;
import org.springframework.web.servlet.modelandview;

public class processinterceptor implements handlerinterceptor{

    @override
    public boolean prehandle(httpservletrequest httpservletrequest, httpservletresponse httpservletresponse, object handler)
            throws exception {
        // todo auto-generated method stub 
        // 指定白名单域名   http://localhost:8000,http://localhost:8000
        list<string> whilelist  = new vector<string>(); 
        whilelist.add("http://127.0.0.1:8000");
        whilelist.add("http://localhost:8000");
        string clientip = httpservletrequest.getheader("origin");
        boolean status = false;
        for(string ip : whilelist) {
            if(clientip!=null&&clientip.equals(ip)) {
                status = true;
                break;
            }
        }
        /**
         * 网上解决方案是httpservletresponse.setheader("access-control-allow-origin","*");设置后发现，还是不能处理跨域问题，需要指定某一个ip，如：http://127.0.0.1:8000  
         * */
        httpservletresponse.setheader("access-control-allow-origin",status?clientip:null);  
        //响应头设置  
        httpservletresponse.setheader("access-control-allow-headers", "content-type,content-length, authorization, accept,x-requested-with");  
        //响应类型
        httpservletresponse.setheader("access-control-allow-methods","put,post,get,delete,options");  
        httpservletresponse.setheader("x-powered-by","jetty");  
        httpservletresponse.setheader("access-control-allow-credentials","true");
        string method= httpservletrequest.getmethod();  
        if (method.equals("options")){  
            httpservletresponse.setstatus(200);  
            return false;  
        }  
  
        system.out.println(method+",status:"+status+",clientip:"+clientip);  
  
        return true;  
    }

    @override
    public void posthandle(httpservletrequest request, httpservletresponse response, object handler,
            modelandview modelandview) throws exception {
        // todo auto-generated method stub
        
    }

    @override
    public void aftercompletion(httpservletrequest request, httpservletresponse response, object handler, exception ex)
            throws exception {
        // todo auto-generated method stub
        
    }

}

spring-servlet.xml配置如下：

<mvc:interceptors>  
       <bean class="com.gg.interceptor.processinterceptor"></bean>  
   </mvc:interceptors>  

react客户端代码如下：

model层js代码:
*login({ payload }, { call, put }){
      let formdata = new formdata();
      formdata.append("loginid",payload.loginid);//账号
      formdata.append("password",payload.password);//密码
      const response = yield call(requestguanggao, formdata); 
      yield put({
        type: 'changeloginstatus',
        payload: response,
      });
    },

api层js代码:
export async function requestguanggao(formdata){
  // let formdata = new formdata();
  // formdata.append("loginid",params.loginid);
  // formdata.append("password",params.password);

  console.log("requestgua   >url  :" );
   return request('http://127.0.0.1:8080/guanggao/usercontroller/login.do', {
    method: 'post', 
    mode: 'cors', 
    body:formdata,
  });   
}

通过以下设置，react跨域问题就处理好了。