smtp-server.js

var smtp = require("smtp-protocol");
var MailParser = require("mailparser").MailParser;
var fs = require("fs");
var path = require("path");

var mails = [];
var config;

function randomInt(low, high) {
  return Math.floor(Math.random() * (high - low) + low);
}

/**
 * Processes a mail
 * @param mail
 */
function process(parsed) {
  mails.push(parsed);
  // Log to console if enabled
  if (!config.quiet) {
    console.log(parsed.headers);
    console.log(parsed.html || parsed.text);
    console.log();
  }
  // Write to file if enabled
  if (config.dump) {
    var filename = new Date().getTime() +
      "-" + randomInt(10000, 99999) + ".json";
    var savePath = path.join(config.dump, filename);
    var text = JSON.stringify(parsed, null, 2);
    fs.writeFile(savePath, text, function (err) {
      if (err) {
        return console.log(err);
      }
    });
  }
  //trim list of emails if necessary
  while (mails.length > config.maxEmails) {
    mails.splice(1, 1);
  }
}

/**
 * Returs a new MailParser instance. Use a new instance for each email.
 * @returns {*|MailParser} MailParser instance
 */
function getMailparser() {
  var mailParser = new MailParser();
  mailParser.on("end", process);
  return mailParser;
}

function start() {
  smtp.createServer(function (req) {

    if (config.whitelist) {
      req.on("from", function (from, ack) {
        if (config.whitelist.length == 0 || config.whitelist.indexOf(from) !== -1)
          ack.accept();
        else ack.reject()
      });
    }

    req.on("message", function (stream, ack) {
      // New MailParser instance for each mail
      var mailParser = getMailparser();
      // Receive data
      stream.on("data", function (d) {
        mailParser.write(d);
      });
      // All data received
      stream.on("end", function () {
        mailParser.end("");
      });

      ack.accept();
    });

  }).listen(config.smtpPort);
}

module.exports = {
  start: function () {
    start()
  },
  getMails: function () {
    return mails;
  },
  setConfig: function (configArg) {
    config = configArg;
  }
};