System Design

FUNCTION REQUIREMENTS:

- user can login/logout
- user can post the article
- user can upload file
- user can searching
- user can like, comment, follow

NON FUNCTION REQUIREMENTS:

- high availability, latency < 500ms
- total users: 100M
- daily active user: 1M
- 1 user upload 2 image per day
- image size < 5MB
--> Write 1 * 2 * 5MB * 1M = 10MB = 10TB
- QPS: Write: 1M * 2(image upload) / (24hours * 60 minutes * 60 seconds) == 25 QPS
- QPS: Read: 1M * 50 / (24hours * 60 minutes * 60 seconds) == 580 QPS
==> READ HEAVY
- No lost for image

API Design

Login: - request: { username, password} - response: { accessToken, refreshToken }
Logout - request: { token } - response: boolean
Post Article - request: { userId, title, description, content, hastag } - response: articleId
Upload File - request: { string base 64 } - response: file_url
Searching - request: { keyword } - response: [ article ]
Like - request: { userId, articleId } - response: boolean
Comment - request: { userId, articleId, content } - response: commentId | Comment
Follow - request: { currentUserId, toUserId } - response: boolean

DB Schema

Design system

Getting started

Installation

Clone the repository

git clone https://github.com/anhtt2211/social-api.git

Switch to the repo folder

cd social-api

Install dependencies

npm install

Create file .env from .env.example and fill it

cp .env.example .env

Run migration

npm run migration:run <db_name>

Running on docker

Build images

docker-compose build

Run on docker

docker-compose up

NPM scripts

npm start - Start application
npm run start:watch - Start application in watch mode
npm run test - run Jest test runner
npm run start:prod - Build application

Swagger API docs

This example repo uses the NestJS swagger module for API documentation. NestJS Swagger - www.swagger.io

anhtt2211/nestjs-boilerplate