notification to subscribers on groups

mongoDB.js

@@ -39,6 +39,15 @@ const getDB = new Promise((resolve, reject) => {
             return DB.usersCol.findOne({ _id });
         }
 
+        let usernamesCache = {}
+        DB.getUsernameByIdCache = async (userid)=>{
+            if(usernamesCache[userid]) return usernamesCache[userid];
+            const _id = new mongo.ObjectID(userid);
+            let user = await DB.usersCol.findOne({ _id });
+            usernamesCache[userid] = user.username;
+            return usernamesCache[userid];
+        }
+
         DB.newUser = (userInformation)=>{
             return DB.usersCol.insertOne(userInformation).catch((err)=>{
                 console.log(err);

notifications.js

@@ -3,36 +3,33 @@ const DBGetter = require("./mongoDB.js");
 
 const Notifications = {
     async sendEmail(to, subject, html) {
-        // create reusable transporter object using the default SMTP transport
         let transporter = nodemailer.createTransport({
           host: "mail.emmint.com",
           port: 465,
-          secure: true, // true for 465, false for other ports
+          secure: true,
           auth: {
-            user: "noreply@emmint.com", // generated ethereal user
-            pass: process.env.EMAILPASS, // generated ethereal password
+            user: "noreply@emmint.com",
+            pass: process.env.EMAILPASS,
           },
         });
       
-        // send mail with defined transport object
         let info = await transporter.sendMail({
-          from: '"EMI Social" <noreply@emmint.com', // sender address
-          to, // list of receivers
-          subject, // Subject line
-          //text: "Hello world?", // plain text body
-          html, // html body
+          from: '"EMI Social" <noreply@emmint.com',
+          to, 
+          subject,
+          html,
         });
       
         console.log("Message sent: %s", info.messageId);
     },
-    async youGotANewPostComment(postId, whoPostedId, Message){
+    async youGotANewPostComment(postId, whoPostedId, message){
         const DB = await DBGetter.getDB;
         const post = await DB.getPost(postId)
         const profile = await DB.getProfileCache(post.profileid);
         const user = await DB.getUserById(profile.userid);
         const senderProfile = await DB.getProfileCache(whoPostedId);
         let subject = senderProfile.profile.firstName + " comment on your post";
-        let message = `
+        let html = `
 <p>Hello ${profile.profile.firstName},</p>
 
 <p>You got a comment on your post:</p>
@@ -45,7 +42,7 @@ const Notifications = {
 <p>Comment:</p>
 
 <blockquote cite="https://social.emmint.com/">
-<p>${Message}</p>
+<p>${message}</p>
 </blockquote>
 <figcaption>— ${senderProfile.profile.firstName} ${senderProfile.profile.lastName}</figcaption>
 
@@ -54,21 +51,56 @@ const Notifications = {
 <p>Blessings</p>
 
 `;
-        this.sendEmail(user.username, subject, message)
+        this.sendEmail(user.username, subject, html)
     },
-    async youGotANewPost(toProfileId, whoPostedId, Message){
+    async yourGroupGotANewPost(groupProfile, whoPostedId, message){
+      const DB = await DBGetter.getDB;
+      let subscribedPromise = Object.keys(groupProfile.subscribed).map((profileid)=>{
+        return DB.getProfileCache(profileid);
+      });
+      let subscribed = await Promise.all(subscribedPromise);
+      let usersPromise = subscribed.map((profile)=>{
+        return DB.getUsernameByIdCache(profile.userid);
+      });
+      let users = await Promise.all(usersPromise);
+      const senderProfile = await DB.getProfileCache(whoPostedId);
+      users.forEach((user, index)=>{
+        let profile = subscribed[index];
+        let subject = senderProfile.profile.firstName + " posted on one of the groups you follow";
+        let html = `
+<p>Hello ${profile.profile.firstName},</p>
+
+<p>${groupProfile.profile.firstName} ${groupProfile.profile.lastName} have new post:</p>
+
+<blockquote cite="https://social.emmint.com/">
+<p>${message}</p>
+</blockquote>
+<figcaption>— ${senderProfile.profile.firstName} ${senderProfile.profile.lastName}</figcaption>
+
+<p><a href="https://social.emmint.com/">Check it on the site</a></p>
+
+<p>Blessings</p>
+
+`;
+        this.sendEmail(user, subject, html)
+      })
+    },
+    async youGotANewPost(toProfileId, whoPostedId, message){
       const DB = await DBGetter.getDB;
       const profile = await DB.getProfileCache(toProfileId);
+      if(profile.isGroup){
+        return this.yourGroupGotANewPost(profile, whoPostedId, message);
+      }
       const user = await DB.getUserById(profile.userid);
       const senderProfile = await DB.getProfileCache(whoPostedId);
       let subject = senderProfile.profile.firstName + " post on your profile";
-      let message = `
+      let html = `
 <p>Hello ${profile.profile.firstName},</p>
 
 <p>You got a new post:</p>
 
 <blockquote cite="https://social.emmint.com/">
-<p>${Message}</p>
+<p>${message}</p>
 </blockquote>
 <figcaption>— ${senderProfile.profile.firstName} ${senderProfile.profile.lastName}</figcaption>
 
@@ -77,7 +109,7 @@ const Notifications = {
 <p>Blessings</p>
 
 `;
-      this.sendEmail(user.username, subject, message)
+      this.sendEmail(user.username, subject, html)
   }
 }