nodemailer-direct-transport

Direct transport for Nodemailer

Usage no npm install needed!

<script type="module">
  import nodemailerDirectTransport from 'https://cdn.skypack.dev/nodemailer-direct-transport';
</script>

README

Direct SMTP transport module for Nodemailer

Applies for Nodemailer v1.x and not for v0.x where transports are built-in.

Usage

Install with npm

npm install nodemailer-direct-transport

Require to your script

var nodemailer = require('nodemailer');
var directTransport = require('nodemailer-direct-transport');

Create a Nodemailer transport object

var transporter = nodemailer.createTransport(directTransport(options))

Where

  • options defines connection data
    • options.name hostname to be used when introducing the client to the MX server
    • options.logger optional bunyan compatible logger instance. If set to true then logs to console. If value is not set or is false then nothing is logged
    • options.debug if set to true, then logs SMTP traffic, otherwise logs only transaction events
    • options.port optional port to use for connecting to MX servers (defaults to MTA standard 25)
    • options.retryDelay optional timeout in ms for retrying failed messages (defaults to 15 minutes)
    • getSocket optional method that is called every time a new connection is made against the SMTP server. This method can provide an existing socket to be used instead of creating a new one

Example

var transport = nodemailer.createTransport(directTransport({
    name: 'smtp.example.com' // should be the hostname machine IP address resolves to
}));

send callback

Send callback includes the following arguments

  • error if the mail was not sent
    • error.errors is an array of error responses (one response for one MX exchange)
      • error.errors[].recipients an array of failed recipients
      • error.errors[].response Error response from the SMTP server
  • info if at least one mail was sent or is pending
    • info.accepted an array of recipients that were accepted
    • info.rejected an array of recipients that were rejected
    • info.pending an array of pending recipient objects (messages that were not rejected permanently and are retried later)
      • info.pending[].recipients an array of recipient addresses that are still pending
      • info.pending[].response Response from the SMTP server
    • info.errors An array of errors (for these exhanges that rejected mail)

Issues

Direct transport is very inefficient as it queues all e-mails to be sent into memory. Additionally, if a message is not yet sent and the process is closed, all data about queued messages is lost. Thus direct transport is only suitable for low throughput systems, where the message can be processed immediately.

While not being 100% reliable (remember - if process exits, entire queue is lost), direct transport can still handle sending errors, graylisting and such. If a message can not be sent, it is re-queued and retried later.

License

MIT