Haraka plugin to store mail in a fixed maildir

maildir.ini

# This file must be placed in "config" directory of your Haraka server.

# Maildir directory. Can be relative to Haraka server directory, or absolute.
# Available tokens:
#       %d -> domain
#       %n -> username
path=/var/mails/%d/%n

# Permission of new directories.
dir_mode=0750

# Permission of new files.
file_mode=0650

# Rspamd score when a mail is considered spam and should be moved
# to spam folder
# rspamd_spam_threshold=15.0
rspamd_move_to_spam=true
rspamd_spam_threshold=8.0

maildir.js

/**
 * @overview: Stores email into a single maildir folder, optionally obeying rspamd-score.
 * Needs Node v10
 */

const os = require('os');
const fs = require('fs');
const path = require('path');
const util = require('util');
const stream = require('stream');

const link = util.promisify(fs.link);
const unlink = util.promisify(fs.unlink);
const pipeline = util.promisify(stream.pipeline);
const mkdir = util.promisify(fs.mkdir);

exports.register = function() {
  this.load_maildir_ini();
};

/**
 * Saves email when the smtp server enqueues it.
 */
exports.hook_queue = function(next, connection) {
  const plugin = this;
  const cfg = plugin.cfg.main;
  const txn = connection.transaction;
  const options = {};

  // If message is SPAM, send to Junk folder
  const rspamd_header = txn.header.headers_decoded['x-rspamd-score'];
  if (rspamd_header && cfg.rspamd_move_to_spam) {
    const spam_score = rspamd_header[0];
    if (spam_score > cfg.rspamd_spam_threshold) {
      plugin.loginfo("Email is spam, move to spam folder. Score: " + util.inspect(spam_score));
      options.folder = ".Junk";
    }
  }

  plugin.deposit(options, connection).then(() => next(OK), err => {
    plugin.logerror(`Failed to deliver mail: ${(err && err.stack) || err}`);
    next(DENYSOFT);
  });
};

exports.deposit = async function(params, connection) {
  const plugin = this;
  const cfg = plugin.cfg.main;
  const dirMode = parseInt(cfg.dir_mode, 8);
  const fileMode = parseInt(cfg.file_mode, 8);

  let maildir = cfg.path;
  //const [name, domain] = params.user.split('@');
  //maildir = maildir.replace('%d', domain);
  //maildir = maildir.replace('%n', name);

  const folder = params.folder ? path.join(maildir, params.folder) : maildir;
  const fileName = getFileName(connection);

  // Create subdirectories if needed
  const f = {};
  await Promise.all(['tmp', 'cur', 'new'].map(async dir => {
    const subfolder = path.join(folder, dir);
    f[dir] = path.join(subfolder, fileName);
    await mkdir(subfolder, { mode: dirMode, recursive: true })
      .catch(err => err.code === 'EEXIST' || Promise.reject(err))
  }));

  // Write the file
  const fileStream = fs.createWriteStream(f['tmp'], { flags: 'w', mode: fileMode });
  await pipeline(connection.transaction.message_stream, fileStream);
  await link(f['tmp'], f['new']);
  await unlink(f['tmp']);
};

exports.load_maildir_ini = function() {
  const plugin = this;
  plugin.cfg = plugin.config.get('maildir.ini', 'ini', () => {
    plugin.load_maildir_ini();
  });
};

/**
 * Unique name of the file inside the maildir.
 * For filename uniqueness, connection uuid is used.
 * Thanks: http://cr.yp.to/proto/maildir.html
 * @return {string}
 */
const getFileName = (connection) =>
  `${Date.now()}.${connection.uuid}.${os.hostname()}`;

maildir.md

maildir

Stores the email into a file in a maildir structure. See here for more info about the maildir format. This plugin is loosely based on the one in https://github.com/swerter/haraka-plugins, but stores mails in a single, fixed maildir.

Configuration

This plugin uses the configuration maildir.ini in INI format.

• path = /var/emails (REQUIRED)

  Set the destination directory to store the email

• dir_mode = 0750 (REQUIRED)

  Set the permission of the new directory

• rspamd_move_to_spam = true (REQUIRED)

  Whether to move a email marked as spam to the .Spam folder instead of into the inbox.

• rspamd_spam_threshold = 8.0 (REQUIRED)

  Above which threshold the email should be moved to the spam folder.