OnePic is a product that makes it easy to use one profile picture everywhere. The product let's you have one unique URL that when any website uses under img tag renders the image on the page. THe product also let's you upload multiple pictures and set one of them as active.
<img src="https://onepic.relog.in/arpit" />
The OnePic URL for user arpit will be https://onepic.relog.in/arpit which when put under img tag renders the one active profile picture of that user. This URL will be used by all other social media to render arpit's profile picture. This way when arpit marks some other of his profile picture as active, it will take its effect on all the websites automatically, without needing him to go and update the picture on each site individually.
The problem statement is something to start with, be creative and dive into the product details and add constraints and features you think would be important.
- user to manage multiple profile pictures and mark one as active
- one unqiue URL used by all the websites to render the user's profile picture
- 50000 photo uploads per minute
- read to write ratio 100000:1
- make your high-level components operate with high availability
- ensure that the data in your system is durable, not matter what happens
- define how your system would behave while scaling-up and scaling-down
- make your system cost-effective and provide a justification for the same
- describe how capacity planning helped you made a good design decision
- think about how other services will interact with your service
- ensure the data in your system is never going in an inconsistent state
- ensure your system is free of deadlocks (if applicable)
- ensure that the throughput of your system is not affected by locking, if it does, state how it would affect
Create a design document of this system/feature stating all critical design decisions, tradeoffs, components, services, and communications. Also specify how your system handles at scale, and what will eventually become a chokepoint.
Do not create unnecessary components, just to make design look complicated. A good design is always simple and elegant. A good way to think about it is if you were to create a spearate process/machine/infra for each component and you will have to code it yourself, would you still do it?
To understand the nuances and internals of this system, build a prototype that
- built a simple static site server that serves user uploaded images
- CRUD to manage profile pictures and marking one active
- render the active profile picture whenever the image is requested through the URL
This is a recommended tech-stack for building this prototype
| Which | Options |
|---|---|
| Language | Golang, Java, NodeJS, C++ |
| Database | Pick your favourite |
These are the common pitfalls that you should keep in mind while you are building this prototype
- serving images through API server is simple than it looks
- static file server
- read heavy systems serving static content
- database schema design
If you find this assignment helpful, please
- share this assignment with your friends and peers
- star this repository and help it reach a wider audience
- give me a shoutout on Twitter @arpit_bhayani, or on LinkedIn at @arpitbhayani.
This assignment is part of Arpit's System Design Masterclass - A masterclass that helps you become great at designing scalable, fault-tolerant, and highly available systems.