Open Source RWSERVE plugin

Nodemailer

Send mail using server-side JavaScript

Motivation

There are many applications where sending an email in response to an HTTP POST is required. This module is a proof-of-concept plugin that demonstrates one way to send SMTP messages using the Nodemailer module.

Customization

This plugin is open-source and may be extended to provide additional features, such as:

• Accepting additional form elements such as user profile data or answers to survey questions.
• Customizing the outgoing emails with different messages based on form inputs.
• Storing email addresses using a file or database.
• Sending HTML instead of plain text.

Download

The plugin module is available from NPM . Before proceeding, you should already have Node.js and RWSERVE configured and tested.

This module should be installed on your web server in a well-defined place, so that it can be discovered by RWSERVE. The standard place for public domain plugins is /srv/rwserve-plugins.

Configuration is Everything

Make the software available by declaring it in the plugins section of your configuration file. For detailed instructions on how to do this, refer to the plugins documentation on the Read Write Tools HTTP/2 Server website.

TL;DR

How it works

The plugin receives POST requests originating from a standard HTML <form> , which uses content-type application/x-www-form-urlencoded. The request body should contain one form element, named recipient, which contains an email address.

An email envelope is prepared using the given recipient plus the values for from subject, and text which are defined in the message-defaults section of the configuration file.

The email is queued for delivery using SMTP using the values for host, port, authMethod and connectionTimeout defined in the transport section of the configuration file. Values for authUser and authPassword should be entirely omitted unless required by your SMTP provider.

When communication with the SMTP server is complete, the last reply code received from the transport is placed in the special header nodemailer-smtp-reply . A value of 250 generally indicates success, and can be interpreted as "email was queued for delivery". Other values are generally failures. (Search for "smtp reply code" to help diagnose those problems.)

The HTTP request/response cycle completes with status code 200 and a response body with content-type application/json. The returned JSON payload contains:

• accepted an array of addresses that were accepted by SMTP
• rejected an array of addresses that were rejected by SMTP
• response the last communication from the SMTP server with reply code
• messageId a unique email identifier generated by SMTP for logging

Sample HTML

<form action='https://localhost:7443/customer-service/signup' method=POST>
    <label>Email address <input type=text name=recipient /></label>
    <input type=submit value=Submit />
</form>

CURL Test

You can also use CURL to send a request to the plugin like this:

Cookbook

A full configuration file with typical settings for a server running on localhost port 7443, is included in this NPM module at etc/nodemailer-config. To use this configuration file, adjust these variables if they don't match your server setup:

Deployment

Once you've tested the plugin and are ready to go live, adjust your production web server's configuration in /etc/rwserve/rwserve.conf and restart it using systemd . . .

. . . then monitor its request/response activity with journald.

Prerequisites

This is a plugin for the Read Write Tools HTTP/2 Server, which works on Linux platforms.

Review

License

The rwserve-nodemailer plugin is licensed under the MIT License.

Availability