Requirements

Functional Requirements:

• Allow reservation of a parking spot.
• Process payment for the reservation.
• Enable parking of a car in the reserved spot.
• Support early departure before reservation time expires.
• Gate check-in/out.
• Handle no show.

Non-Functional Requirements:

• Scalable
• prevent double booking (consistency)
• reliable

Capacity Estimation

daily users, depends on location. in a very central lot with many 200+ lots one can expect 2000-5000 users. So one server + dB may not be enough in peak times, but could work still. increase capacity on demand.

API Design

• GET number free lots
• POST checkin
• POST checkout
• POST payment
• ...

High-Level Design

We need a Server that handles booking request, has acess to a DB logging users, payment info, bookings, etc. also the server handles the current state (how many free lots) based on the database. must periodically check in database if a timewindow closed but there was no checkout by the user... Then it should bill extra per hour.

Database Design

SQl database: with a table with customer id name +payment info. then a table with actions like personid 223 booked a lot from 2pm till 4pm... this may be enough

Detailed Component Design

Easily scalable like this, as we can simply increase the number of servers allowing for more users. the database can be a bottleneck, but it can also be scaled.