echoServer.js

// This is a template script created for some testing
// This is not the actual transformer server
const cluster = require("cluster");
const http = require("http");
const numCPUs = require("os").cpus().length;
const url = require("url");
require("./util/logUtil");

function start(port) {
  if (!port) {
    port = 9292;
  }

  if (cluster.isMaster) {
    console.log(`Master ${process.pid} is running`);

    // Fork workers.
    for (let i = 0; i < numCPUs; i++) {
      cluster.fork();
    }

    cluster.on("exit", (worker, code, signal) => {
      console.log(`worker ${worker.process.pid} died`);
    });
  } else {
    // Main server body
    http
      .createServer(function(request, response) {
        var pathname = url.parse(request.url).pathname;

        // Adding logic for a call that will invalidate cache
        // for particular module in order that next require call for
        // that module will reload the same
        if (request.method == "POST") {
          var body = "";
          var respBody = "";

          request.on("data", function(data) {
            body += data;

            // Too much POST data, kill the connection!
            // 1e6 === 1 * Math.pow(10, 6) === 1 * 1000000 ~~~ 1MB
            if (body.length > 1e8) request.connection.destroy();
          });

          request.on("end", async function() {
            try {
              // need to send 400 error for malformed JSON
              console.log(body);
              response.statusCode = 200;
              response.end(body);
            } catch (se) {
              response.statusCode = 500; // 500 for other errors
              response.statusMessage = se.message;
              console.log(se.stack);

              response.end();
            }
          });
        } else {
          console.log(url.parse(request.url, true).query);
        }
      })
      .listen(port);
    console.log(`Worker ${process.pid} started`);
  }
  console.log("echoServer: started");
}

start(9292);