nodejs设置服务代理跨域

//导入所需的模块
const http = require('http');
const https = require('https');
const url = require('url');
const querystring = require('querystring');

//创建HTTP服务器
http.createServer(function(req,res) {
  //获取请求URL
  let aimUrl = req.url;

  //解析请求地址
  let urlObj = url.parse(aimUrl,true);

  //获取目标地址
  let targetUrl = urlObj.query.url;

  //解析参数
  let paramsObj = urlObj.query;

  //删除URL中的url参数
  delete paramsObj.url;

  //将JSON格式的querystring参数转化为querystring
  let params = querystring.stringify(paramsObj);

  //设置目标URL
  let options = {
    protocol: url.parse(targetUrl).protocol,
    hostname: url.parse(targetUrl).hostname,
    port: url.parse(targetUrl).port,
    path: url.parse(targetUrl).pathname + '?' + params,
    method: 'GET',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded'
    }
  };

  //发起请求
  let request = https.request(options, function(response) {
    //设置响应数据类型
    res.writeHead(response.statusCode, {'Content-Type': 'application/json'});

    //监听data事件
    response.on('data', function(chunk) {
      res.write(chunk);
    });

    //监听end事件
    response.on('end', function() {
      res.end();
    });
  });

  //设置请求超时时间
  request.setTimeout(3000, function() {
    res.writeHead(500, {'Content-Type': 'application/json'});
    res.write(JSON.stringify({error: 'timeout'}));
    res.end()
  });

  //监听错误事件
  request.on('error', function(error) {
    res.writeHead(500, {'Content-Type': 'application/json'});
    res.write(JSON.stringify({error: error}));
    res.end();
  });

  //设置请求方式
  request.method = req.method;

  //发起请求
  if (req.method == 'POST' || req.method == 'PUT') {
    req.on('data', (data) => {
      request.write(data);
    });
    req.on('end', () => {
      request.end();
    });
  } else {
    request.end();
  }
}).listen(8080, 'localhost');