Airline Ticket Booking Backend System

Objective

• We need to build a backend feature for an airline company. our end-user is going to be someone who wants to book flights and query about flights, so we need a robust system to actually help them give the best experience possible.

• This Doc is going to solely focus on Backend Part. We want to prepare the whole backend keeping in the fact in mind that code-base should be easily maintainable as much as possible.

Requirements

• A user should be able to search for flights from one place to another.
  • User should be able to mention the src and dest details.
  • User should be able to select the date of journey. {V2 -> multicity and round trip implementation}
  • User should be able to select the class of the flights. (Non-mandatory, have some default value)
  • User should be able to select the number of seats. (Non-mandatory, have some default value)
  • List down the flights based on the above data.
  • The best available flights should be shown based on price and least journey time.
  • Need to support pagination so that we can list chunk of flights at one point of time.
  • Filter of flights should be supported based on Price, Departure Time, Arrival time, Journey time, etc. {V2 -> some more filters}
• A user should be able to book a flight considering that user is reisterred on the platform.
  • Excess luggage addition feature should be supported.
• Tracking of the flight prices should be possible; user should be notified for any price drops or any delays. {V2 -> some more notification service}
• For booking, the user has to make a payment. (dummy)
• User should be able to list their previous and upcoming flights.
• User should be able to download their boarding pass if they have done Web Check-in.
• Web Check-in should be supported.
  • {V2 -> Seat Selection feature}
• Notification via email for Web check-in.
• Reqview system for users iff they have booked the flight.
  • Star based review system
  • Listing of flights should involve review display.
• User should be able to authenticate to our system using email and password.
• Cancellation of a flight should be supported and cancellation returns (dummy).
• While making a booking, a persone can reserve more than one seat with one login id.

Non-Functional Requirements

• We can expect that we are going to have more number of flight searches than flight bookings.
• The system needs to be accurate in terms of booking.(No Over booking)
• Expect that we will be having approx 1,00,000 total users, 5,00,000 bookings might happen in one quarter.
• So in one day we can expect 10,000 bookings.
• System should be capable of scaling up to atleast 3x the current estimated traffic.
• The system should handle realtime updates to flight prices, before user makes the final booking.
• Concurrency should be handled, using RDBMS should be the good solution.

Capacity Estimations

• Storage Estimations:
  • For upcoming 5 years, 80,00,000 bookings, 2,00,000 users.
  • Considering all the users records and booking records take 10 MB of data, then overall 10 TB of memory should be fine for out initial pilot run.
• Traffic estimates: If we consider 30:1 as the search:booking ratio, then max we can expect 1,50,000 search queries a day. (2 queries/sec)

Authentication Service

URL: https://github.com/omkarharade/Authentication-Service-AirlineTicketBooking.git

Flights Service

URL: https://github.com/omkarharade/FlightsAndSearchService-AirlineTicketBooking.git

Booking Service

URL: https://github.com/omkarharade/BookingService-AirlineTicketBooking.git

Email Service

URL: https://github.com/omkarharade/ReminderService-AirlineTicketBooking.git

API Gateway Service

URL: https://github.com/omkarharade/APIGateway-AirlineTicketBooking.git