postmailer/nodemailer.js

HTTP POST -> SMTP proxy, as Express middleware

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

function commaSplit(string) {
	return string.match(/([^,]|"([^"]|\\.)*")+/g) || [];
}

function emailFromUrls(urls) {
	for (var i = 0; i < urls.length; i++) {
		if (/^mailto\:/.test(urls[i])) {
			return urls[i].replace('mailto:', '');
		}
	}
	return null;
}

function sendWithNodemailer(hub, options) {
	options = options || {};
	var maxInline = options.maxInline || 500*1024; // 500kb maximum inline document
	var transport = nodemailer.createTransport(options.transport || directTransport());
	transport.on('log', function (message) {
		hub.emit('log', message);
	});

	hub.handle('mail', function (mail, next) {
		var hub = this;

		var email = emailFromUrls(mail.target.urls);
		if (!email) return next();

		// Replace URLs with email addresses
		var messageHeaders = {};
		function transformField(value) {
			if (Array.isArray(value)) return value.map(transformField);
			return value.replace(/<([^<>]+\:\/\/[^<>]+)>/g, function (original, url) {
				var match = hub.canonical(url);
				var email = emailFromUrls(match.urls);
				if (email) return '<' + email + '>';
				return original;
			});
		}
		for (var key in mail.headers) {
			messageHeaders[key] = transformField(mail.headers[key]);
		}

		// Envelope sender
		var sender = (messageHeaders['sender'] || commaSplit(messageHeaders['from'])[0]);
		// strip name and <>
		sender = sender.replace(/^\s*"([^"\\]|\\.)*"/, '').replace(/(^[^<]*<|>[^>]*$)/g, '');

		var nodeMail = {
			from: messageHeaders['from'],
			to: [email],
			cc: messageHeaders['cc'] ? commaSplit(messageHeaders['cc']) : [],
			subject: messageHeaders['subject'] || '',
			headers: mail.headers,
			envelope: { /* only send to the "to" address, don't include CC/BCC */
				from: sender,
				to: email
			}
		};
		nodeMail.headers['to'] = nodeMail.headers['to'] || (JSON.stringify(mail.target.name) + ' <' + mail.target.email + '>');

		// Format as inline text, inline HTML, inline image (with HTML) or attachment
		var inline = mail.length && mail.length < maxInline && mail.filename;
		var contentType = mail.headers['content-type'] || 'text/plain';
		if (inline && /^text\/plain($|\s|;)/.test(contentType)) {
			nodeMail.text = copyStream(request);
		} else if (inline && /^text\/html($|\s|;)/.test(contentType)) {
			nodeMail.html = copyStream(request);
		} else {
			var filename = mail.filename || ('attachment.' + mime.extension(contentType));
			var cid = null;
			if (/^image\//.test(contentType) && inline) {
				cid = crypto.pseudoRandomBytes(16).toString('hex') + '-' + email;
				nodeMail.html = '<img src="cid:' + cid + '" style="max-width: 100%; max-height: 100%" alt="' + filename.replace(/&/g, '&amp;').replace(/"/g, '&quot;').replace(/</g, '&lt') + '"/>';
			}
			nodeMail.attachments = [{
				contentType: contentType,
				content: mail.message,
				cid: cid,
				filename: filename
			}];
		}

		hub.emit('log', 'Forwarding to ' + nodeMail.to);

		transport.sendMail(nodeMail, function (error) {
			if (error) {
				hub.emit('error', error);
				return next();
			}
		});
	});
}

module.exports = sendWithNodemailer;