Stateful Web App: MyClothes.com
- MyClothes.com allows people to buy clothes online.
- There’s a shopping cart
- Our website is having hundreds of users at the same time
- We need to scale, maintain horizontal scalability and keep our web application as stateless as possible
- Users should not lose their shopping cart
- Users should have their details (address, etc) in a database
- Let’s see how we can proceed!
Introduce Stickiness (Session Affinity)
Introduce User Cookies
Introduce Server Session
Storing User Data in a database
Scaling Reads
Scaling Reads (Alternative) – Lazy Loading
Multi AZ – Survive disasters
Security Groups
In this lecture we’ve discussed… 3-tier architectures for web applications
- ELB sticky sessions
- Web clients for storing cookies and making our web app stateless
- ElastiCache
- For storing sessions (alternative: DynamoDB)
- For caching data from RDS
- Multi AZ
- RDS
- For storing user data
- Read replicas for scaling reads
- Multi AZ for disaster recovery
- Tight Security with security groups referencing each other