Requirements

Functional Requirements:

• Create a short URL for a given long URL.
• Return the long URL associated with a given short URL.
• System needs to provide the analytics for each short url ( like for example number of clicks for the given short url )

Non-Functional Requirements:

• Low latency :- for the given short url need to return the long url very fast
• Horizontal Scalability :- When the load is increasing , then the servers will be automatically create replicas so that they can accomodate the incoming load.
• High Reliability :- System should need to be respond with correct response
• High Availability :- System need to be available for almost all the time
• Low Redirect lantecy :- System should redirect the short url to the correct long url in few milli seconds

API Design

. /generateUrl :- POST API , that will generate the short url for the given long url

. /getUrl :- GET API, that will extract the long url corresponding to the short url

High-Level Design

1. Cloud cluster to deploy the url service ( kubernetes cluster, Docker Spawn etc...)
2. Load Balancer to distribute the load evenly to all the pods ( for reliablity).
3. Database ( Relational database) to store the records of the generated short urls for the given long urls.
4. Cache for the faster retrievals
5. ApiGate way to provide reverse proxy to the servers
6. A CDN to get the urls fast

Detailed Component Design

. CDN will deliver the urls faster to the users based on the regions, so that the users will redirect in few milli seconds.

. API Gateway - will be act as a authentication server so that the valid users only allowed to use the service.

. Load Balancer - When the load is coming, load balancer can redirect the load to different pods, so that the single pod cannot be overwhelmed by the load.