Appointment Scheduling Nodes.js Backend

Appointment Scheduling with Google Calender API and Node JS

Change Configurations in .env.sample file (Important step!!!)

First off, please configure Google Calender API credentials, Port no. inside .env.sample file then change the name of .env.sample file to .env using below command (for linux and unix), or vice-versa.

mv .env.sample .env

For example:

Before Config

PORT = <PUT YOUR PORT NO>

GOOGLE_CLIENT_ID = <PUT YOUR GOOGLE CLIENT ID>
GOOGLE_CLIENT_SECRET = <PUT YOUR GOOGLE CLIENT SECRET>
GOOGLE_REDIRECT_END_POINT = <PUT YOUR GOOGLE REDIRECT ENDPOINT>
GOOGLE_REDIRECT_URI = <PUT YOUR GOOGLE OAUTH REDIRECT URI>
GOOGLE_CALENDAR_ID = <PUT YOUR GOOGLE CALENDAR ID>

After Config

PORT = 8081

GOOGLE_CLIENT_ID = 200692833635-6diasdfasdfc15fhuphe8jnq76ldcjttq32.apps.googleusercontent.com
GOOGLE_CLIENT_SECRET = RssSmuC2lHqcjGId1FB8FYJs
GOOGLE_REDIRECT_END_POINT = /oauth/callback
GOOGLE_REDIRECT_URI = https://quickstart-1569289058700.appspot.com
GOOGLE_CALENDAR_ID = [email protected]

Please leave other configuration as it is!

For you own GCP, OAuth and Calendar API (OAuth Approach)

For Authorized redirect URIs, we use combination of GOOGLE_REDIRECT_URI + GOOGLE_REDIRECT_END_POINT (from the .env file), that would be, for example,

https://quickstart-1569289058700.appspot.com/oauth/callback

If you have your own redirect point on your GCP, please update GOOGLE_REDIRECT_END_POINT with your own redirect end-point for example,

https://youGooleGCPAppEngine.url.com/youOwnRedirect/EndPoint

For GOOGLE_CALENDAR_ID, just use your own Google Calendar's ID.

So, in .env file, the final configuration should look something similar like below,

PORT = 8081

GOOGLE_CLIENT_ID = 200692833635-6diasdfasdfc15fhuphe8jnq76ldcjttq32.apps.googleusercontent.com
GOOGLE_CLIENT_SECRET = RssSmuC2lHqcjGId1FB8FYJs
GOOGLE_REDIRECT_END_POINT = /youOwnRedirect/EndPoint
GOOGLE_REDIRECT_URI = https://youGooleGCPAppEngine.url.com
GOOGLE_CALENDAR_ID = [email protected]
GOOGLE_CALENDAR_SCOPE = https://www.googleapis.com/auth/calendar
GOOGLE_TOKEN_ACCESS_TYPE = offline

START_OF_DAY = 00:01:00
END_OF_DAY = 23:59:00

START_TIME = 09:00:00
END_TIME = 18:00:00

APPOINTMENT_DURATION = 40
APPOINTMENT_INTERVAL = 5

TIME_FORMAT = HH:mm:ss

NODE_PATH = ./src
NODE_ENV: production

Points to be noted (Other Important Instructions)

• As per the requirement, I have tested the app features in UTC timezone.
• Please do not forget to put your Google Calender's timezone to UTC.
• Every time you start the app, the time zone is set to UTC. For example, as you can see below, start script from package.json file "start": "TZ=utc node -r dotenv/config dist/server.js"
• DO NOT forget to make your Google Calender publicly accessable if you want to use other gmail-id to access the calender. You can easily change this under your Calender Setting Options.
• You have to allow every access to google oauth consent to make booking and fetching timeslots.

Install Dependencies: (I prefer Yarn personally)

yarn install

Start server in Production mode:

yarn start

Start server in Development mode with nodemon:

yarn dev

Make app production ready:

yarn build && yarn serve

Google Cloud Platform end-point URLs

Days

https://quickstart-1569289058700.appspot.com/days?year=YYYY&month=MM

eg: https://quickstart-1569289058700.appspot.com/days?year=2019&month=11

Timeslots

https://quickstart-1569289058700.appspot.com/timeslots?year=YYYY&month=MM&day=DD

eg: https://quickstart-1569289058700.appspot.com/timeslots?year=2019&month=11&day=29

Booking

https://quickstart-1569289058700.appspot.com/book?year=YYYY&month=MM&day=DD&hour=HH&minute=MM

eg: https://quickstart-1569289058700.appspot.com/book?year=2019&month=11&day=29&hour=14&minute=15

About the logger

• Only error and warn level of logs are logged in file called logs.log, however, all level of logs can be traced at console.

Thank you! :)

Given Requirements:

• All appointments are 40 minutes long and have fixed times, starting from 9–9:40 am
• Ensure there is always a 5 minutes break in between each appointment
• Appointments can only be booked during weekdays from 9 am to 6 pm
• Bookings can only be made at least 24 hours in advance
• Appointments cannot be booked in the past
• For simplicity, use UTC time for all bookings and days and ISO 8601 format for timeslots

Endpoints:

GET bookable days

Requires a year and month. Note that months must not be zero-indexed.

GET /days?year=yyyy&month=mm

Returns an array of all days in the specified month, each of which has the field hasTimeSlots, which is false if there are no time slots available, based on the requirements listed above.

{
  "success": true,
  "days": [
    { "day": 1,  "hasTimeSlots": false },
    ...
    { "day": 31, "hasTimeSlots": true }
  ]
}

GET available time slots

Requires a year, month, and day.

GET /timeslots?year=yyyy&month=mm&day=dd

Returns a list of all 40-minute time slots available for that day as an array of objects that contain a startTime and endTime in ISO 8601 format.

{
  "success": true,
  "timeSlots": [
    {
      "startTime": "2019-09-04T09:00:00.000Z",
        "endTime": "2019-09-04T09:40:00.000Z"
    },
    {
      "startTime": "2019-09-04T09:45:00.000Z",
        "endTime": "2019-09-04T10:25:00.000Z"
    },
    ...
  ]
}

POST book an appointment

Requires a year, month, day, hour, and minute.

POST /book?year=yyyy&month=MM&day=dd&hour=hh&minute=mm

Returns a boolean field success. If the booking was successful, also return startTime and endTime.

If not successful, return a message, a string for the error message.

// Success
{
    "success": true,
  "startTime": "2019-09-04T10:30:00.000Z",
    "endTime": "2019-09-04T11:10:00.000Z"
}

// Fail
{
    "success": false,
    "message": "Invalid time slot"
}

Error messages for this POST request are:

• Invalid time slot: The time slot provided was not one of the time slots returned in the GET available time slots request
• Cannot book with less than 24 hours in advance
• Cannot book outside bookable timeframe: The time slot provided was not on a weekday between 9 am and 5 pm
• Cannot book time in the past

Error messages for ALL endpoints should be in this format:

{
    "success": false,
    "message": "Invalid time slot"
}

Where message contains the corresponding error message, such as Request is missing parameter: year