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README.md

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+# objcache
+
+Cache serde-able objects with Redis.
+
+## Quick overview
+
+Imagine you have the following:
+
+1) A struct or enum that implements `Serialize` and `Deserialize`
+
+```rust
+#[derive(Serialize, Deserialize)]
+struct Item {
+    value: usize,
+}
+```
+
+2) An expensive function that creates an instance of that struct or enum
+
+```rust
+async fn get_item(v: usize) -> Result<Item, Error> {
+    // your business logic here
+    Ok(Item { value: v })
+}
+```
+
+3) A redis connection
+
+```rust
+let client = RedisClient::new((IpAddr::V4(Ipv4Addr::LOCALHOST), 6379)).unwrap();
+```
+
+This library lets you add a cache to your application by `wrap()`ing your function:
+
+```rust
+let item = client.wrap(
+    get_item,
+    &RedisCacheArgs {
+        lock_name: b"item_lock",
+        key_name: b"item",
+        expiry: Duration::from_secs(5),
+    },
+)(100)
+.await?;
+
+assert_eq!(item.value, 100);
+```
+
+That's it! Any call to the wrapped function will reuse the latest response if it is not
+older than 5 seconds.
+
+## Not implemented
+
+* Cache depending on the input parameters
+* Non-async wrap functions (should be easy to implement with some refactoring)
+
+## Status
+
+More of a proof of concept, there may be some big hidden issues.
+
+## Available methods
+
+|Method|Use case|
+|---|---|
+|`wrap()`|You want to unconditionally cache a response|
+|`wrap_opt()`|Your function returns an `Option<T>` and you only want to cache `Some` responses|
+|`wrap_const()`|You want to select whether or not to cache depending on a separate parameter taking `CacheDecision`|
+|`wrap_on()`|You have a function that takes your `Item` and returns a `CacheDecision`|