feat(notification): add user notification

- Add event listener and emitter on a new article created
- Add option for followers to receive notification when a new articles created
- Add functionalities of choosing preferred notificastions
- Add unit tests
- Add swagger documentation
[Delivers #165413114]

app.js

@@ -7,6 +7,9 @@ import session from 'express-session';
 import routes from './routes';
 import registerApiDocEndpoint from './config/swagger';
 import pass from './config/passport/localstrategy';
+import initNotification from './helpers/utils/eventHandlers';
+
+initNotification();
 
 const isProduction = process.env.NODE_ENV === 'production';
 

controllers/article.controller.js

@@ -1,6 +1,7 @@
 import ArticleHelper from '../helpers/article';
 
 /**
+ * @author Samuel Niyitanga
  * @exports ArticleController
  * @class ArticleController
  * @description Handles all related articles functioanlities

controllers/notification.controller.js

@@ -0,0 +1,44 @@
+import NotificationHelper from '../helpers/notification';
+
+/**
+ * @author Samuel Niyitanga
+ * @exports ArticleController
+ * @class ArticleController
+ * @description Handles all related notifications functioanlities
+ * */
+class NotificationController {
+  /**
+ * @param  {object} req - Request object
+ * @param {object} res - Response object
+ * @returns {object} response
+ *  @static
+ */
+  static async setNotification(req, res) {
+    await NotificationHelper.setOption(req);
+    return res.status(200).send({ Message: 'Notification option setted.' });
+  }
+
+  /**
+ * @param  {object} req - Request object
+ * @param {object} res - Response object
+ * @returns {object} response
+ *  @static
+ */
+  static async unsetNotification(req, res) {
+    await NotificationHelper.UnsetOption(req);
+
+    return res.status(200).send({ Message: 'Notification successfully unsetted.' });
+  }
+
+  /**
+ * @param  {object} req - Request object
+ * @param {object} res - Response object
+ * @returns {object} response
+ *  @static
+ */
+  static async getNotificationByUser(req, res) {
+    const notification = await NotificationHelper.getByUser(req);
+    return res.status(200).send({ notification });
+  }
+}
+export default NotificationController;

helpers/article.js

@@ -3,10 +3,12 @@ import uniqid from 'uniqid';
 import Joi from 'joi';
 import PassportHelper from './passport';
 import db from '../models';
+import emitter from './eventEmitters';
 
 const { Article, User, Like } = db;
 
 /**
+ * @author Samuel Niyitanga
  * @exports ArticleHelper
  * @class ArticleHelper
  * @description Article Helper
@@ -49,6 +51,11 @@ class ArticleHelper {
       slug,
       authorId: articleAuthor.id
     });
+    emitter.emit('onFollowPublish', {
+      title,
+      authorId: articleAuthor.id,
+      slug
+    });
     const values = {
       userData,
       article
@@ -145,7 +152,7 @@ class ArticleHelper {
   }
 
   /**
-     * Check article owner
+     * Update article
      * @param {object} req - an object
      * @return {object} Returns response
      * @static
@@ -164,10 +171,10 @@ class ArticleHelper {
   }
 
   /**
-     * Return if the user is owner
+     * Delete article
      * @param {object} req - an object
      * @param {object} res - an object
-     *@return {boolean} Return true if user matche
+     *@return {boolean} Return true if deleted
      */
   static async deleteArticle(req) {
     const currentSlug = req.params.slug;
@@ -177,7 +184,7 @@ class ArticleHelper {
   }
 
   /**
-     * Return if the user is owner
+     * Return all article
      *@return {object} Return all articles
      */
   static async getAllArticles() {
@@ -195,7 +202,7 @@ class ArticleHelper {
   /**
      * Return one article
      * @param {object} req - an object
-     *@return {object} Return all articles
+     *@return {object} Return  article
      */
   static async getOneArticle(req) {
     const article = await Article.findOne({

helpers/eventEmitters.js

@@ -0,0 +1,5 @@
+import { EventEmitter } from 'events';
+
+const emitter = new EventEmitter();
+
+export default emitter;

helpers/notification.js

@@ -0,0 +1,238 @@
+import db from '../models';
+import passportHelper from './passport';
+import mailSender from './utils/mail-sender';
+
+const {
+  User, Follows, Notification
+} = db;
+
+/**
+ * @author Samuel Niyitanga
+ * @exports NotificationHelper
+ * @class NotificationHelper
+ * @description Notification Helper
+ * */
+class NotificationHelper {
+  /**
+     * Set notification option
+     * @param {object} req - an object
+     * @return {object} Returns response
+     * @static
+     */
+  static async setOption(req) {
+    const { option } = req.params;
+    const user = await User.findOne({ where: { id: req.user.id } });
+    const notifsArray = user.dataValues.notification;
+    notifsArray.push(option);
+    const optionSet = await user.update({ notification: notifsArray });
+    return optionSet;
+  }
+
+  /**
+     * Unset notification option
+     * @param {object} req - an object
+     * @return {object} Returns response
+     * @static
+     */
+  static async UnsetOption(req) {
+    const { option } = req.params;
+    const user = await User.findOne({ where: { id: req.user.id } });
+    const notifsArray = user.dataValues.notification;
+    const optionIndex = notifsArray.indexOf(option);
+    notifsArray.splice(optionIndex, 1);
+    const optionUnsetted = await user.update({ notification: notifsArray });
+    return optionUnsetted;
+  }
+
+  /**
+     * Check if option exists
+     * @param {object} req - an object
+     * @param {object} res - an object
+     * @param {object} next - an object
+     * @return {boolean} Returns if true if it is valid else return false
+     * @static
+     */
+  static async isOptionAvailable(req, res, next) {
+    const user = await User.findOne({ where: { id: req.user.id } });
+    const index = user.dataValues.notification
+      .findIndex(notification => notification === req.params.option);
+    if (index !== -1) {
+      return res.status(422).send({ status: 422, Error: 'You already have this Option set' });
+    }
+    next();
+  }
+
+  /**
+     * Check if option exists
+     * @param {object} req - an object
+     * @param {object} res - an object
+     * @param {object} next - an object
+     * @return {boolean} Returns if true if it is valid else return false
+     * @static
+     */
+  static async isOptionIn(req, res, next) {
+    const user = await User.findOne({ where: { id: req.user.id } });
+    const index = user.dataValues.notification
+      .findIndex(notification => notification === req.params.option);
+    if (index === -1) {
+      return res.status(422).send({ status: 422, Error: 'You don\'t have this Option set' });
+    }
+    next();
+  }
+
+  /**
+     * Check if it is valid params
+     * @param {object} req - an object
+     * @param {object} res - an object
+     * @param {object} next - an object
+     * @return {boolean} Returns if true if it is valid else return false
+     * @static
+     */
+  static isValidOption(req, res, next) {
+    const validValues = ['email', 'in-app', 'follower', 'articleFavorite'];
+    if (validValues.indexOf(req.params.option) === -1) {
+      return res.status(422).send({ status: 422, Error: 'Only option must be email,in-app,follower or articleFavorite' });
+    }
+    next();
+  }
+
+  /**
+   * @param {integer} authorId
+   * @returns {object} return list of followers
+   */
+  static async getFollowersList(authorId) {
+    const lists = await Follows.findAll({
+      where: { follower: authorId },
+      attributes: ['following']
+    });
+    return lists;
+  }
+
+  /**
+   * @param {object} userIds
+   * @param {string} userType
+   * @returns {Array} return array of object
+   */
+  static async serializeUsers(userIds, userType) {
+    const type = userType === 'follower' ? 'follower' : 'following';
+    const userList = [];
+    await Promise.all(userIds.map(async (currentId) => {
+      const userInfo = await passportHelper.findRecord(User, currentId[type]);
+      userList.push({
+        id: currentId[type],
+        username: userInfo.dataValues.username,
+        bio: userInfo.dataValues.bio,
+        image: userInfo.dataValues.image,
+        email: userInfo.dataValues.email,
+        notification: userInfo.dataValues.notification
+      });
+    }));
+    return userList;
+  }
+
+  /**
+   * @param {object} followers
+   * @returns {object} return emails
+   */
+  static getfollowersWithEmailOption(followers) {
+    const followersWithEmails = [];
+    followers.forEach((follower) => {
+      if (follower.notification.indexOf('email') !== -1) {
+        followersWithEmails.push(follower);
+      }
+    });
+    return followersWithEmails;
+  }
+
+  /**
+   * @param {object} followers
+   * @param {integer} authorId
+   * @param {string} articleSlug
+   * @returns {object} return followers
+   */
+  static getfollowersWithAppOption(followers) {
+    const followersWithApp = [];
+    followers.forEach((follower) => {
+      if (follower.notification.indexOf('in-app') !== -1) {
+        followersWithApp.push(follower);
+      }
+    });
+    return followersWithApp;
+  }
+
+  /**
+   *  Send notification email when users they follow publish new articles
+   * @param {string } email - A user aemail
+   * @param {string} author
+   * @param {string} title
+   * @returns {object} return email to send
+   */
+  static sendEmailToFollowers(email, author, title) {
+    return mailSender.send({
+      email,
+      subject: `${author} created a new article`,
+      html: `<html>You can check <strong>${title}</strong> created on Author Haven</html>`
+    });
+  }
+
+  /**
+   *  Send notification email when articles they favorited have new interaction
+   * @param {string } email - A user aemail
+   * @param {string} user - People who interacted with an article
+   * @param {string} title
+   * @returns {object} return email to send
+   */
+  static sendEmailOnInteraction(email, user, title) {
+    return mailSender.send({
+      email,
+      subject: `Reaction on Article by  ${user} on Author Haven`,
+      html: `<html>On Author Haven<strong>${title}</strong> had a new interaction </html>`
+    });
+  }
+
+  /**
+   * @param {object}  followers followers object
+   * @param {string}  title
+   * @param {string}  username
+   * @returns {array} return array of notification object
+   */
+  static inAppNotifications(followers, title, username) {
+    const notifications = [];
+    followers.forEach((follower) => {
+      if (follower.notification.indexOf('follower') !== -1) {
+        const singleNotification = {
+          userId: follower.id,
+          notificationMessage: `New article called ${title} was created by ${username} `,
+        };
+        notifications.push(singleNotification);
+        return;
+      }
+      if (follower.notification.indexOf('articleFavorite') !== -1) {
+        const singleNotification = {
+          userId: follower.id,
+          notificationMessage: `Reaction on Article  called ${title}  by ${username} `,
+        };
+        notifications.push(singleNotification);
+      }
+    });
+    return notifications;
+  }
+
+  /**
+       * Return one article
+       * @param {object} req - an object
+       *@return {object} Return  article
+       */
+  static async getByUser(req) {
+    const article = await Notification.findAll({
+      where: { userId: req.user.id },
+      include: [{
+        model: User,
+        as: 'user',
+        attributes: ['username', 'bio', 'image']
+      }]
+    });
+    return article;
+  }
+}
+export default NotificationHelper;