System requirements
Functional:
User
- User could browse and view events
- User could view the details of the event
- User could make the order with multiple events
- User could reverse a order with the seat
- User could make the payment
Merchant
- Merchant could publish new event
- Merchant could update the event
- Merchant could view the ticket availability, analysis
Non-Functional:
- Consistency (payement)
- Availability
- Latency (view, browse)
Capacity estimation
Estimate the scale of the system you are going to design...
- Assume total user 100M
- DAU 10M -> Peak DAU 50M
- View 10pages per day, 10 pages per day
- View DAU 100M, 1k QPS to browse (peak view DAU 5k)
- Reservation 1% rate, DAU 0.1M -> Peak DAU 0.5M -> QPS 1 and peak QPS 5
For merchant
- 1M merchant (100 events)
- 100M events in total
- Events has metadata 1K and details 1M
- 100M * 1K = 100GB
- 100M * 1M = 100PB
API design
Define what APIs are expected from the system...
GET fetchOpenEvents
GET fetchEventInDetails(eventId)
POST makeReservation(orderId, event)
POST checkOut(orderId)
POST makeAnEvent
Database design
Defining the system data model early on will clarify how data will flow among different components of the system. Also you could draw an ER diagram using the diagramming tool to enhance your design...
High-level design
You should identify enough components that are needed to solve the actual problem from end to end. Also remember to draw a block diagram using the diagramming tool to augment your design. If you are unfamiliar with the tool, you can simply describe your design to the chat bot and ask it to generate a starter diagram for you to modify...
Request flows
Explain how the request flows from end to end in your high level design. Also you could draw a sequence diagram using the diagramming tool to enhance your explanation...
Detailed component design
Dig deeper into 2-3 components and explain in detail how they work. For example, how well does each component scale? Any relevant algorithm or data structure you like to use for a component? Also you could draw a diagram using the diagramming tool to enhance your design...
Trade offs/Tech choices
Explain any trade offs you have made and why you made certain tech choices...
Failure scenarios/bottlenecks
Try to discuss as many failure scenarios/bottlenecks as possible.
Future improvements
What are some future improvements you would make? How would you mitigate the failure scenario(s) you described above?