View Source ExKits.Cache (ex_kits v0.2.7)

This module provides a simple cache framework for storing and retrieving key-value pairs.

Examples

Retrieve a value from the cache:

```Elixir
storage = SomeImplement.new()
ExKits.Cache.fetch(storage, :key, [{:ttl, 3000}], fn _key ->
  {:commit, "value"}
end)
|> IO.puts()
```

Evict a value from the cache:

```Elixir
storage = SomeImplement.new()
ExKits.Cache.evict(storage, :key)
```

Security Warning

This module provides a basic implementation of a cache framework and should not be used in production environments without proper security review and testing.

Summary

Functions

evict(storage, key)

This function removes the cached value with the given key from the cache storage.

fetch(storage, key, opts, fallback)

This function retrieves a value from the cache storage with the given key. If the value is not found, the fallback function is called to generate a new value, which is then stored in the cache storage and returned. If the value is found, it is returned directly.

Types

fallback()

@type fallback() :: (k() -> {:commit, v()} | {:ignore, v()})

k()

@type k() :: term()

put_opts()

@type put_opts() :: [{:ttl, pos_integer() | :infinity}]

storage()

@type storage() :: ExKits.Cache.Storage.t()

v()

@type v() :: term() | nil

Functions

evict(storage, key)

@spec evict(storage(), k()) :: any()

This function removes the cached value with the given key from the cache storage.

The storage argument is a cache storage, which is an opaque data structure that holds the cached key-value pairs. The key argument is the key of the value to remove from the cache.

Examples

```Elixir
storage = SomeImplement.new()
ExKits.Cache.fetch(storage, :key, [], fn _key ->
{:commit, "value"}
end)
|> IO.puts()

ExKits.Cache.evict(storage, :key)
```

fetch(storage, key, opts, fallback)

@spec fetch(storage(), k(), put_opts(), fallback()) :: v()

The storage argument is a cache storage, which is an opaque data structure that holds the cached key-value pairs. The key argument is the key of the value to retrieve.

The opts argument is a list of put options, which can be used to set a time-to-live (TTL) for the cached value.

The fallback argument is a function that takes the cache key as an argument and returns either a {:commit, value} tuple to indicate that the value should be stored in the cache, or a {:ignore, value} tuple to indicate that the value should not be stored in the cache.

The function returns the cached value, or nil if the value is not found and the fallback function returns a {:ignore, value} tuple. If the fallback function returns a {:commit, value} tuple, the value is stored in the cache storage and returned.

Examples

iex> storage = SomeImplement.new()
iex> ExKits.Cache.fetch(storage, :key, [{:ttl, 3000}], fn _key ->
  {:commit, "value"}
end)
|> IO.puts()