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List functional requirements for the system (Ask the chat bot for hints if stuck.)...
checking parking locations and availability
book parking slots on each location
able to track enter/exit of vehicle
support different type of vehicle
support different type of payments
List non-functional requirements for the system...
highly available
scale ability
Estimate the scale of the system you are going to design...
assume there are 200 parking slots on each location
currently we have 100 locations
in average there are 200 vehicles check in/out every day
so we have number below:
QPS > 1 per seconds, it is very low
Storage: each information has parking info + vehicle info (plate, type) + payment info, order info ~= 10 k
10 * 200 * 365 * 50 = 36500000 k = 36500 mb ~= 36.5 gb
the storage is also low
to make system more reliable, we can have 2 or 3 instance and each have
about 1 gb ram and 2 core cpu will be sufficient.
Define what APIs are expected from the system...
/api/getLocations
get /api/{location}/slots
get /api/{location}/{slotNum}
post /api/{location}/{slotNum}
post /api/order
get /api/order/{orderNum}
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...
//location
Location
ParkingSlot
Vehicle
Order
Payemnt
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...
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...
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...
Explain any trade offs you have made and why you made certain tech choices...
Try to discuss as many failure scenarios/bottlenecks as possible.
What are some future improvements you would make? How would you mitigate the failure scenario(s) you described above?