smtp-server-as-promised

smtp-server-as-promised

This module provides promisified version of smtp-server module. The API is the same as for smtp-server, except listen method which return Promise object and callback options which are Promise objects.

Additionally, stream argument for onData promise is changed to PromiseReadable object if options.usePromiseReadable is true.

Requirements

This module requires Node >= 4.

Installation

npm install smtp-server-as-promised

Usage

smtp-server-as-promised can be used like standard smtp-server module:

const {SMTPServerAsPromised} = require('smtp-server-as-promised')

constructor

const server = new SMTPServerAsPromised(options)

Create new SMTPServer instance.

Example:

const server = new SMTPServerAsPromised({
  port: 2525,
  usePromiseReadable: true,
  onConnect, onMailFrom, onData, onError
})

Options are the same as for original smtp-server constructor, except that callback handlers are Promise objects or async functions:

onConnect

async function onConnect (session) {
  console.log(`[${session.id}] onConnect`)
}

onAuth

async function onAuth (auth, session) {
  if (auth.method === 'PLAIN' && auth.username === 'username' && auth.password === 'password') {
    return {user: auth.username}
  } else {
    throw new Error('Invalid username or password')
  }
}

This method must return the object with user property.

onMailFrom

async function onMailFrom (from, session) {
  console.log(`[${session.id}] onMailFrom ${from.address}`)
  if (from.address.split('@')[1] === 'spammer.com') {
    throw new Error('we do not like spam!')
  }
}

An errors can be thrown and then are handled by server in response message.

onRcptTo

async function onRcptTo (to, session) {
  console.log(`[${session.id}] onRcptTo ${to.address}`)
  if (from.address.split('@')[1] === 'spammer.com') {
    throw new Error('we do not like spam!')
  }
}

usePromiseReadable

options.usePromiseReadable = true

Callback handler onData provides stream object as an instance of PromiseReadable class if options.usePromiseReadable options is true

onData

const server = new SMTPServerAsPromised({usePromiseReadable: true, onData})

async function onData (stream, session) {
  console.log(`[${session.id}] onData started`)
  session.messageLength = 0

  for (let chunk; (chunk = await stream.read()) !== null;) {
    console.log(`[${session.id}] onData got data chunk ${chunk.length} bytes`)
    session.messageLength += chunk.length
  }

  console.log(`[${session.id}] onData finished after reading ${session.messageLength} bytes`)
}

stream object is a standard stream.Readable object if options.usePromiseReadable is false.

onError

async function onError (e) {
  console.log('Server error:', e)
}

listen

const promise = server.listen(port[,host][,backlog])

Start the server instance. This method returns promise which returns address as its value.

Example

async function main () {
  const address = await server.listen(2525)
  console.log(`Listening on [${address.address}]:${address.port}`)
}

close

const promise = server.close()

Stop the server from accepting new connections.

Example

async function main () {
  // ...
  await server.close()
  console.log(`Server was stopped`)
}

Promise

This module uses any-promise and any ES6 Promise library or polyfill is supported.

Ie. bluebird can be used as Promise library for this module, if it is registered before.

require('any-promise/register/bluebird')
const {SMTPServerAsPromised} = require('smtp-server-as-promised')

License

Copyright (c) 2016-2017 Piotr Roszatycki [e-mail]

MIT

Changelog

v0.1.0 2017-04-10

• Use the lastest smtp-server module on MIT license
• new Buffer() is obsoleted.