003/node.js--代理服务(解决跨域问题)

业务描述：

1。web前端发送http请求

2。web后端为https协议

如何保证web前端发送http请求到web后端（跨域问题：域名不一致即跨域），

因此用node.js写了个代理服务，转发前端http请求到后端，再获取后端数据返回给前端。

代码如下所示：

'use strict';

const express = require('express');
const fs = require('fs');
const path = require('path');
const https = require('https');
const http=require('http');  
const cookieParser = require('cookie-parser');
const bodyParser = require('body-parser');
const app = express();
const url = require("url");
app.use(cookieParser());
app.use(bodyParser.urlencoded({
  extended: true
}));
app.use(bodyParser.json());

//设置跨域访问
app.all('*', function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "http://localhost:8080");
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
  res.header('Access-Control-Allow-Credentials', true);
  res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");
  res.header("X-Powered-By", ' 3.2.1');
  res.header("Content-Type", "application/json;charset=utf-8");
  if (req.method == "OPTIONS") res.send(200);
  else next();
});
// Https代理请求
app.post('/rancher', function(req1, res1) {
  let urlbody=url.parse(req1.body.url)
  console.log("urlbody=========");
  console.log(urlbody);
  let postData =req1.body.postData||'';
  var opts = {
      method:req1.body.type,
      host:urlbody.host,
      port:urlbody.port||'',
    //   path:urlbody.path+(urlbody.search||''),
      path:urlbody.path,
      headers:{
          'Content-Type':'application/json',
          'Content-Length':postData.length,
          'Authorization':'Basic xx',
          'Cookie':'',
          'Cluster-id':req1.body.cid||''
      },
      rejectUnauthorized:false
  }
  console.log("opts=========");
  console.log(opts);
  var req = https.request(opts,function(res){
      var datas = [];
      var size = 0;
      res.on('data',function(data){
          datas.push(data);
          size += data.length;
      })
      res.on('end', function(){
          var buff = Buffer.concat(datas, size);
          console.log('success'+datas);
          res1.send(buff);
      })
  })
  req.on('error',function(err){
      console.log('异常,异常原因'+err);
  })
  if (req1.body.type!="get") {
    req.write(postData);
  }
  req.end();

});

// Http代理请求
app.post('/http/rancher', function(req, res1) {
  let urlbody=url.parse(req.body.url)
  console.log("urlbody=========");
  console.log(urlbody);
  let postData =req.body.postData||'';
  //发送 http Post 请求
  var opts = {
    method:req.body.type,
    host:urlbody.hostname,
    port:urlbody.port&&urlbody.port||'',
    path:urlbody.path,
    headers:{
        'Content-Type':'application/json',
        'Content-Length':postData.length,
        'Authorization':'Basic xx',
        'Cookie': 'xx',
    },
  }
  var req=http.request(opts, function(res) {
      console.log('Opts:',opts);
      console.log('Status:',res.statusCode);
      console.log('headers:',JSON.stringify(res.headers));
      res.setEncoding('utf-8');
      res.on('data',function(chun){
          console.log('body分隔线---------------------------------
');
          console.info(chun);
          res1.send(chun);
      });
      res.on('end',function(){
          console.log('No more data in response.********');
      });
  });
  req.on('error',function(err){
      console.error(err);
  });
  req.write(postData);
  req.end();
});

let server = app.listen(8089, function() {
  let host = server.address().address;
  let port = server.address().port;

  console.log('Example app listening at http://%s:%s', host, port);
});