Route: /slow is very slow (takes 5 seconds to respond)
Solution: implement caching using Redis!
Implement a caching approach so that when the initial GET request to /api, it takes 5 seconds as usual with the
exception that the response value will be saved to the cache.
But all subsequent GET requests to /api should be served from the cache. This request should be instant, e.g. not take 5 seconds to respond. The cache should expire after 1 minute. After that the first GET request to /api will take 5 seconds to respond and the cache miss flow will occur
A Express middleware module that can be imported onto any route on our server. The middleware function will check the cache store for the cached data for a route and serves the data in the cache back (cache hit) to the client. Otherwise, if the data has not been cached, the middleware lets the request fall-through and hit the route.
Module should have:
- a method which returns a function that can be mounted as middleware
- a method to save a key-value pair to the cache
- a method to retrieve a value from the cache
How does a non-cached request differ from a request served from cache? This is your baseline for your test specifications.
Is there a way to achieve the goal without the getter and setter methods? Yes, but it might require some spoon-bending. After this step you will have built a caching middlware with base similarity to other popular express middlware modules. \o/ :sparkles:
Hint: "fall-through middlware"
