System requirements

Functional:

1. generate unique short alias
2. redirection from short url to original long url
3. custom URL
4. URL expiration date

Non-Functional:

1. scalable
2. highly available
3. secured access
4. analytics

Capacity estimation

total users - 1 million

active users - 10^5 users/day ~ 1user/sec ~ 1QPS

API design

API required - getURL {url short code, long url, short url, expiry date), postURL (long URL, expiry date), deleteURL (url short code, long url, short url), updateURL (url short code, long URL, custom short URL, expiry date)

Database design

database table - userid, username, url short code, long URL, short URL, expiry date

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

1. user/client provide LONG URL and request for shortened URL
2. request goes via LB which distrubutes traffic across web servers

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?