node-http-proxy如何解析目标url？答案

【问题标题】：How does node-http-proxy parse the target url?node-http-proxy如何解析目标url？
【发布时间】：2018-08-10 20:27:17
【问题描述】：

我遇到了一个问题，我觉得node-http-proxy 正在更改我的目标链接。下面我举了几个例子。

我使用 express 作为我的服务器并使用 Metaweather API。

问题是我能够从下面的端点获取数据 https://www.metaweather.com/api/location/2487956/ https://www.metaweather.com/api/location/2487956/2013/4/30/

但是当我尝试从https://www.metaweather.com/api/location/search/?lattlong=36.96,-122.02调用API时

它以状态码 500 失败，我认为 node-http-proxy 在 122.02 之后添加了一些值，因为它没有被 / 关闭

server.js

const express = require("express");
const next = require("next");
const dev = process.env.NODE_ENV !== "production";
const app = next({ dev });
const handle = app.getRequestHandler();

const httpProxy = require("http-proxy");

const proxyOptions = {
  changeOrigin: true
};

const apiProxy = httpProxy.createProxyServer(proxyOptions);

const apiUrl =
  "https://www.metaweather.com/api/location/search/?lattlong=36.96,-122.02";

/*
https://www.metaweather.com/api/location/search/?lattlong=36.96,-122.02 - failed with 500
https://www.metaweather.com/api/location/2487956/ - passed
https://www.metaweather.com/api/location/2487956/2013/4/30/ - passed
*/

app
  .prepare()
  .then(() => {
    const server = express();

    server.use("/api", (req, res) => {
      console.log("Going to call this API " + apiUrl);
      apiProxy.web(req, res, { target: apiUrl });
    });

    server.get("*", (req, res) => {
      return handle(req, res);
    });

    server.listen(3000, err => {
      if (err) throw err;
      console.log("> Ready on http://localhost:3000");
    });
  })
  .catch(ex => {
    console.error(ex.stack);
    process.exit(1);
  });

感谢您调查此问题。

【问题讨论】：

标签： javascript node.js express http-proxy node-http-proxy

【解决方案1】：

我已经在 node-http-proxy 中重现了这种情况。

在common.js 中有一个名为 urlJoin 的函数，它将 req.url 附加到目标 url 的末尾。

我不完全确定意图是什么，但这是一个开始。

这是我的测试：

const urlJoin = function() {
  //
  // We do not want to mess with the query string. All we want to touch is the path.
  //
var args = Array.prototype.slice.call(arguments),
    lastIndex = args.length - 1,
    last = args[lastIndex],
    lastSegs = last.split('?'),
    retSegs;

args[lastIndex] = lastSegs.shift();

//
// Join all strings, but remove empty strings so we don't get extra slashes from
// joining e.g. ['', 'am']
//
retSegs = [
  args.filter(Boolean).join('/')
      .replace(/\/+/g, '/')
      .replace('http:/', 'http://')
      .replace('https:/', 'https://')
];

// Only join the query string if it exists so we don't have trailing a '?'
// on every request

// Handle case where there could be multiple ? in the URL.
retSegs.push.apply(retSegs, lastSegs);

return retSegs.join('?')
};

let path = urlJoin('/api/location/search/?lattlong=36.96,-122.02', '/');

console.log(path);
//                 /api/location/search/?lattlong=36.96,-122.02/

【讨论】：