System requirements
Functional:
- A user can generate a short URL from a long one
- A user can customize the URL
- A user can save the URL to it's profile
- A user can update the URL
- When entering the short URL into the browser, it will be redirected to the original long URL page
Non-Functional:
- The system needs to be highly available
- The system needs to handle a large amount of read request
Capacity estimation
1 url = 100 bytes
each day 1 million short URLs is created
We need 1 GB storage a day
API design
generateShortURL(originalURL, cuztomization): shortURL
getAllSavedURLs(user, id): url[]
updateURL(shortURL) : newShortURL
Database design
Need high scalability so we use noSQL to store URL to shortURL
A user database to store the URL a user created
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...
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?