feat: support for one-click unsubscribe from email clients (#7203)

* feat: sending notifs via ACP creates real notification

re: #7202

* feat: basic integration for one-click unsubscription #7202

* feat: tests for #7202 + bugfix

* feat: added and organized digest unsub tests

closes #7202

src/controllers/accounts/settings.js

@@ -1,7 +1,10 @@
 'use strict';
 
 var async = require('async');
+var nconf = require('nconf');
+var winston = require('winston');
 var _ = require('lodash');
+var jwt = require('jsonwebtoken');
 
 var user = require('../../user');
 var languages = require('../../languages');
@@ -183,6 +186,52 @@ settingsController.get = function (req, res, callback) {
 	], callback);
 };
 
+settingsController.unsubscribe = function (req, res) {
+	if (!req.params.token) {
+		return res.sendStatus(404);
+	}
+
+	jwt.verify(req.params.token, nconf.get('secret'), function (err, payload) {
+		if (err) {
+			return res.sendStatus(403);
+		}
+
+		switch (payload.template) {
+		case 'digest':
+			async.parallel([
+				async.apply(user.setSetting, payload.uid, 'dailyDigestFreq', 'off'),
+				async.apply(user.updateDigestSetting, payload.uid, 'off'),
+			], function (err) {
+				if (err) {
+					winston.error('[settings/unsubscribe] One-click unsubscribe failed with error: ' + err.message);
+					return res.sendStatus(500);
+				}
+
+				return res.sendStatus(200);
+			});
+			break;
+		case 'notification':
+			async.waterfall([
+				async.apply(db.getObjectField, 'user:' + payload.uid + ':settings', 'notificationType_' + payload.type),
+				(current, next) => {
+					user.setSetting(payload.uid, 'notificationType_' + payload.type, (current === 'notificationemail' ? 'notification' : 'none'), next);
+				},
+			], function (err) {
+				if (err) {
+					winston.error('[settings/unsubscribe] One-click unsubscribe failed with error: ' + err.message);
+					return res.sendStatus(500);
+				}
+
+				return res.sendStatus(200);
+			});
+			break;
+		default:
+			res.sendStatus(404);
+			break;
+		}
+	});
+};
+
 function getNotificationSettings(userData, callback) {
 	var privilegedTypes = [];
 

src/emailer.js

@@ -11,6 +11,7 @@ var url = require('url');
 var path = require('path');
 var fs = require('fs');
 var _ = require('lodash');
+var jwt = require('jsonwebtoken');
 
 var User = require('./user');
 var Plugins = require('./plugins');
@@ -216,6 +217,31 @@ Emailer.sendToEmail = function (template, email, language, params, callback) {
 		'List-Unsubscribe': '<' + [nconf.get('url'), 'uid', params.uid, 'settings'].join('/') + '>',
 	}, params.headers);
 
+	// Digests and notifications can be one-click unsubbed
+	let payload = {
+		template: template,
+		uid: params.uid,
+	};
+
+	switch (template) {
+	case 'digest':
+		payload = jwt.sign(payload, nconf.get('secret'), {
+			expiresIn: '30d',
+		});
+		params.headers['List-Unsubscribe'] = '<' + [nconf.get('url'), 'email', 'unsubscribe', payload].join('/') + '>';
+		params.headers['List-Unsubscribe-Post'] = 'List-Unsubscribe=One-Click';
+		break;
+
+	case 'notification':
+		payload.type = params.notification.type;
+		payload = jwt.sign(payload, nconf.get('secret'), {
+			expiresIn: '30d',
+		});
+		params.headers['List-Unsubscribe'] = '<' + [nconf.get('url'), 'email', 'unsubscribe', payload].join('/') + '>';
+		params.headers['List-Unsubscribe-Post'] = 'List-Unsubscribe=One-Click';
+		break;
+	}
+
 	async.waterfall([
 		function (next) {
 			Plugins.fireHook('filter:email.params', {

src/routes/index.js

@@ -35,6 +35,7 @@ function mainRoutes(app, middleware, controllers) {
 	setupPageRoute(app, '/tos', middleware, [], controllers.termsOfUse);
 
 	app.post('/compose', middleware.applyCSRF, controllers.composer.post);
+	app.post('/email/unsubscribe/:token', controllers.accounts.settings.unsubscribe);
 }
 
 function modRoutes(app, middleware, controllers) {

src/socket.io/admin.js

@@ -14,6 +14,7 @@ var userDigest = require('../user/digest');
 var userEmail = require('../user/email');
 var logger = require('../logger');
 var events = require('../events');
+var notifications = require('../notifications');
 var emailer = require('../emailer');
 var db = require('../database');
 var analytics = require('../analytics');
@@ -273,6 +274,30 @@ SocketAdmin.email.test = function (socket, data, callback) {
 		}, callback);
 		break;
 
+	case 'notification':
+		async.waterfall([
+			function (next) {
+				notifications.create({
+					type: 'test',
+					bodyShort: '[[admin-settings-email:testing]]',
+					bodyLong: '[[admin-settings-email:testing.send-help]]',
+					nid: 'uid:' + socket.uid + ':test',
+					path: '/',
+					from: socket.uid,
+				}, next);
+			},
+			function (notifObj, next) {
+				emailer.send('notification', socket.uid, {
+					path: notifObj.path,
+					subject: utils.stripHTMLTags(notifObj.subject || '[[notifications:new_notification]]'),
+					intro: utils.stripHTMLTags(notifObj.bodyShort),
+					body: notifObj.bodyLong || '',
+					notification: notifObj,
+					showUnsubscribe: true,
+				}, next);
+			},
+		]);
+		break;
 	default:
 		emailer.send(data.template, socket.uid, payload, callback);
 		break;