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README.md

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+# warp-caching
+
+This is an example web API that expands on the [todos example in the warp 
+repo](https://github.com/seanmonstar/warp/blob/09f7a71306a46131d8ece7c49c32d21b52e90700/examples/todos.rs) 
+in order to test different methods of caching. I want to know how easy the 
+different methods are to implement and how they rank in performance.
+
+Besides caching, I have added these features on-top of the `todos.rs` example:
+
+* Split up the monolithic `todos.rs` into separate module files.
+* Better rejections using [`anyhow`](https://crates.io/crates/anyhow) errors 
+  that are JSON-ified into HTTP responses using 
+  [`http-api-problem`](https://crates.io/crates/http-api-problem).
+* Added the `Environment` struct that's just a cloneable container for handles 
+  to the database and caches.
+
+## Caching methods
+
+Here I will detail the different methods in this repo and how they performed.
+
+### No cache
+
+Endpoint: `/no_cache/todos`
+
+The baseline. This is approximately the same as the todos example in the warp 
+repo. Since it uses an in-memory database instead of a real database, it 
+actually performs the best out of all of the other options. But, if we were to 
+use a real database or add some delay to each faked database access then we 
+would see that this is actually the slowest option.
+
+### Database result LRU cache
+
+TODO
+
+Similar to [identity_cache](https://github.com/Shopify/identity_cache) in the 
+Ruby on Rails world.
+
+### HTTP response LRU cache
+
+Endpoint: `/lru_cache/todos`
+
+This option also uses the [lru](https://crates.io/crates/lru) crate wrapped in a 
+tokio Mutex, but it stores the entire HTTP response as bytes instead of just the 
+response from the database queries.
+
+warp's `Response` is not cloneable, which prevents it from being stored in a 
+cache directly, so I made a `CachedResponse` struct that serializes from a warp 
+`Reply` and cache it instead. When fetching from the cache, the `CachedResponse` 
+is converted back into a warp `Response` with `Response::builder()`.
+
+### Redis cache
+
+TODO
+
+Should probably use the [redis](https://crates.io/crates/redis) crate.
+
+### Other??
+
+I'd like to test out as many of these options that I can:
+
+* [nginx proxy response cache](https://docs.nginx.com/nginx/admin-guide/content-cache/content-caching/)
+* [memcached](https://memcached.org/)
+* [cached crate](https://lib.rs/crates/cached). I'd like to see if it could 
+  reduce a lot of the boilerplate in my own LRU cache implementation. I tried it 
+  briefly before, but ran into some issues.
+
+## Benchmarks
+
+TODO