System requirements

Functional:

List functional requirements for the system (Ask the chat bot for hints if stuck.)...

Non-Functional:

• System should stay available 24h/24h
• In case of failure of a server, request are redirect to an another instance with the load balancer

Capacity estimation

Estimate the scale of the system you are going to design...

API design

Define what APIs are expected from the system...

• User client api involved only a post request
  • The url parameter in request param
  • and in response the url paramter shortened in payload

Database design

No database needed, we use a key-value store cache, like redis, memdb to store request

• key: url
• value: url-shortened

Url are store in case of cache missed

Cache strategy follow the strategy of LRU to free up some space

High-level design

• A client server, which is a front end GUI for user
  • It send an url , and wait the the url shortened
• A cache: position in front of the load balancer, it return the url shortened if he is already know, in case of cache missed the cache redirect the request to a load balancer who dispatch it to a server
• Load balancer: Is main rôle is to dispatch request between server
  • It serve both for reliabity in cas of a server failure and for scalability

Request flows

A post request is thrown by the client

case1 :

• No cache miss, the cache return the url shortened

case 2:

• Cache miss the request is redirect to the load balancer
• The load balancer analyse the load of the servers and redirect it to the best server
• The server receive a request, and process the shortener for the url specify, it return it to the client and save it to the cache:

Detailed component design

Dig deeper into 2-3 components and explain in detail how they work. For example, how well does each component scale? Any relevant algorithm or data structure you like to use for a component? Also you could draw a diagram using the diagramming tool to enhance your design...

Trade offs/Tech choices

Failure scenarios/bottlenecks

Try to discuss as many failure scenarios/bottlenecks as possible.

Future improvements

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