Requirements

Functional Requirements:

• Create a short URL for a given long URL.
• Return the long URL associated with a given short URL.

Non-Functional Requirements:

• High availability - The service needs to be available and accessible at all times.
• Low Redirect Latency - users will expect redirects to be fast and should ideally be un-noticeable.
• Horizontal Scalability - The system should scale to cater for large peak volumes as well as for growth over time

API Design

All CRUD operations for maintaining shortened URLs. (Delete being an archive function, not a hard delete)

Lookup URL for finding full URL given the short URL.

Login & registration APIs.

High-Level Design

Core service: A Rest API hosted on a Web server backed by a database.

A multi-node caching layer for speed and resilience for url lookup.

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.