procfiled/forward.js

Node.js process manager for Procfile-based applications

// Copyright IBM Corp. 2012,2016. All Rights Reserved.
// Node module: procfiled
// This file is licensed under the MIT License.
// License text available at https://opensource.org/licenses/MIT

var http = require("http");
var url = require("url");
var httpProxy = require("http-proxy");

function startForward(proxy_port, proxy_host) {
  var proxy = httpProxy.createProxyServer({});

  var httpServer = http.createServer(function (req, res) {
    var _url = url.parse(req.url);

    var dest = _url.hostname;
    var port = _url.port || 80;
    var host = "127.0.0.1";

    var target;
    if (proxy_host === "<ANY>" || proxy_host === dest) {
      target = {
        host: host,
        port: port,
      };
      req.url = _url.path;
    } else {
      target = {
        host: dest,
        port: port,
      };
    }

    proxy.web(req, res, { target: target });
  });

  proxy.on("upgrade", function (req, socket, head) {
    proxy.ws(req, socket, head);
  });

  proxy.on("error", function (err, req, res) {
    console.error("Proxy Error: ", err);
    res.writeHead(500);
    res.write("Upstream Proxy Error");
    res.end();
  });

  httpServer.listen(proxy_port);
}

startForward(process.env.PROXY_PORT, process.env.PROXY_HOST);