Nebulex (Nebulex v2.1.1) View Source

Nebulex is split into 2 main components:

  • Nebulex.Cache - caches are wrappers around the in-memory data store. Via the cache, we can put, get, update, delete and query existing entries. A cache needs an adapter to communicate to the in-memory data store.

  • Nebulex.Caching - decorators provide an elegant way of annotating functions to be cached or evicted. By means of these decorators, it is possible the implementation of cache usage patterns like Read-through, Write-through, Cache-as-SoR, etc.

In the following sections, we will provide an overview of those components and how they interact with each other. Feel free to access their respective module documentation for more specific examples, options and configuration.

If you want to quickly check a sample application using Nebulex, please check the getting started guide.

Caches

Nebulex.Cache is the wrapper around the Cache. We can define a cache as follows:

defmodule MyApp.MyCache do
  use Nebulex.Cache,
    otp_app: :my_app,
    adapter: Nebulex.Adapters.Local
end

Where the configuration for the Cache must be in your application environment, usually defined in your config/config.exs:

config :my_app, MyApp.MyCache,
  gc_interval: 3_600_000, #=> 1 hr
  backend: :shards,
  partitions: 2

Each cache in Nebulex defines a start_link/1 function that needs to be invoked before using the cache. In general, this function is not called directly, but used as part of your application supervision tree.

If your application was generated with a supervisor (by passing --sup to mix new) you will have a lib/my_app/application.ex file containing the application start callback that defines and starts your supervisor. You just need to edit the start/2 function to start the cache as a supervisor on your application's supervisor:

def start(_type, _args) do
  children = [
    {MyApp.Cache, []}
  ]

  opts = [strategy: :one_for_one, name: MyApp.Supervisor]
  Supervisor.start_link(children, opts)
end

Otherwise, you can start and stop the cache directly at any time by calling MyApp.Cache.start_link/1 and MyApp.Cache.stop/1.

Declarative annotation-based caching

See Nebulex.Caching.