Requirements

Functional Requirements:

• what do we need to return to the user? send full url and get short url back?
• Long to short URL mapping
• Database to store mapping - cache for faster retrieval
• endpoint hosted & load balancing for scaling

Non-Functional Requirements:

• how fast / reliable is perf requirements - maybe caching layer
• maybe need load balancing
• maybe geo located servers for speed

Capacity Estimation

• need to scale to how many users?
• what size of database do we need?
• how often do we need to rotate the database?
• what kind of retention do we need on the data?
• how to store the data? time series? key/value? traditional relational DB?

API Design

• single endpoint - REST
• POST - /shorturl
  • return str # return shortened URL
• GET - /shorturl
  • return str # long url

High-Level Design

Describe the overall system architecture. Identify the main components needed to solve the problem end-to-end. Use the diagramming tool to create a block diagram.

Database Design

need mapping between in sql short url to long url column. we can optimize further by using cacheing with map . we can load balance across regions by hashing with timestamps and geolocated servers. we can also scale lookup with having hot keys located on single server and hash those short urls to that server specifically. we can scale servers by using he hash method and understanding bandwidth each server can handle and scale when we start approaching bandwidth threshold . preemptively scale. we can use universal hash so we can scale without having to re-hash everything. we can optimize lookup with the cache by having O(1) lookup there and minimize re-balancing with universal hash.

Detailed Component Design

Deep dive into 2-3 key components. Explain how they work, how they scale, discuss tradeoffs, capacity, and any relevant algorithms or data structures.