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:

• Latency and Reliability

API Design

POST api/v1/shorten/:longUrl

-> 201 Created

GET api/v1/long/:shortUrl

-> 301 Moved Permannet

High-Level Design

Here we need to focus on two aspects mainly shorten the url and get the url

We assume 10k writes per second and peak 100k

Then

10,000 * 3600 * 24 = 864 millon url/day

26 billon/month

315 billion/ year

URL shortener:

We will take 58 char left the confusing. We know we need roughly 1T url per year. So taking 58^8 , 8 char shorten url which is 128 T url combination sufficient enough

Storage and DB:

Lets assume temporary and permanent url split. Assume that around 250b urls max length 1 year and 75b max 10 year

Assuming 500 byte per url

So for a single year we need storage of,

250 + 750 = 1T url storage ,

which is 500 TB

We assume 5TB of of per db node so 100 db node needed

Based on number of visit and time created we will create a ranking list and used caching. We assume 1% url mostly visited . Which would be 50 gb . Can be handle with 4*16 shared redis cluster

We assume 100k read per second

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.