Simple server that writes raw HTTP post data to a file.

server.js

var http = require("http");
var fs = require("fs");
var path = require("path");

http.createServer(function(request, response) {
  unique_filename(function(filename) {
    upload_file(filename, request, response);
  });
}).listen(8000);

function upload_file(filename, request, response) {
  var fileStream = fs.createWriteStream(filename);

  request.on('data', function(chunk) {
    fileStream.write(chunk);
  });
  
  request.on('end', function() {
    fileStream.end();
    upload_complete(response);
  });

  fileStream.on('error', function() {
    console.log('error while writing to file');
  });
}

function unique_filename(callback) {
  var filename = ".csv";
  for (var i = 0; i < 10; i++) {
    var c = Math.floor(Math.random() * 26 + 97);
    filename = String.fromCharCode(c) + filename;
  };
  path.exists(filename, function(exists) {
    if (exists) {
      unique_filename(callback);
    } else {
      console.log('Writing ' + filename);
      callback(filename);
    }
  });
}

function upload_complete(response) {
  response.writeHead(201, {'Content-Type': 'text/plain'});
  response.end();
}

console.log("> Running at http://127.0.0.1:8000/");