email-microservice

send email to all the users at specific time according to different time zones of the users

Using Express, Mongoose, node-schedule and nodemailer

Clone repository

git clone https://github.com/sthnaqvi/email-microservice

After repository is cloned, go inside of repository directory and install dependencies there:

cd email-microservice
npm install

To start the server

npm start

API routes

Create a new client: uncomment clientCtrl.createClient() function in app.js file

 clientCtrl.createClient({name: "Sam", email: "sam@xyz.com", city: "Dubai", country: "UAE", password: "test123"});

 POST: http://localhost:9000/api/client/login

Request:

 {
 	"email":"david@xyz.com",
 	"password":"test123"
 }

Response:

 {
     "success": true,
     "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJlbWFpbCI6ImRhdmlkQHh5ei5jb20iLCJjbGllbnRJZCI6IjViMWM0NmRjYWRjYzMwNDg0NjU1Mzg3NiIsImlhdCI6MTUyODY1ODIyOH0.SBTyeyAKbwmppf8Q9WJ5vHWQNQNRY0P7DaxO9lYW0Pk"
 }

Create User API for client to create a new user: Request: with Authorization Header(JWT)

 {
 	"name":"demo",
 	"email":"demo@xyz.com",
 	"offset":"-300",
 	"city":"Lima",
 	"country":"Peru"
 }

Response:

 {
     "success": true,
     "msg": "New user created.",
     "user": {
         "_id": "5b1d8699b05dec1cf3900aca",
         "name": "demo",
         "email": "demo@xyz.com",
         "offset": -300,
         "city": "Lima",
         "country": "Peru",
         "clientId": "5b1c46dcadcc304846553876",
         "__v": 0
     }
 }

How it works

After run npm start start script run node app.js

in app.js file called cron.startCron() function.
in cron.js file startCron() function find total number of unique offset(time zone) in database.
after getting all existing offsets in Array[] call scheduleJob() for each offset.
in scheduleJob()
1. set key value of scheduledOffset[offset] = true; to store running offset(timezone) cron.
2. call otherTimeToLocalTime(offset); to get time hour & minute (8:00AM of particular time zone to local time).
3. call schedule.scheduleJob(rule, function (){ }) (function of node-schedule package) to schedule job.
  1. when cron execute call findUsersAndSendEmail() function to find users of particular time zone and send Email in batch 100 users.

Accounts

Database: Mongodb(create a test account on MLab)
SMTP: GMAIL test account