distributed

defmodule Distributed do
	@moduledoc """
	Make your systems distributed, replicated, scaled well, easily.

	[![Hex Version](https://img.shields.io/hexpm/v/distributed.svg?style=flat-square)](https://hex.pm/packages/distributed) [![Docs](https://img.shields.io/badge/api-docs-orange.svg?style=flat-square)](https://hexdocs.pm/distributed) [![Hex downloads](https://img.shields.io/hexpm/dt/distributed.svg?style=flat-square)](https://hex.pm/packages/distributed) [![GitHub](https://img.shields.io/badge/vcs-GitHub-blue.svg?style=flat-square)](https://github.com/ertgl/distributed) [![MIT License](https://img.shields.io/hexpm/l/distributed.svg?style=flat-square)](LICENSE.txt)
	---

	### Tutorial

	This is an example of a replicated `GenServer`.

		defmodule Storage.KV do

			use GenServer

			def start_link() do
				GenServer.start_link(__MODULE__, [initial_state: %{}], name: __MODULE__.process_id())
			end

			def init(opts \\\\ []) do
				{:ok, Keyword.get(opts, :initial_state, %{})}
			end

			def process_id() do
				Storage.KV
			end

			def handle_cast({:set, key, value}, state) do
				{:noreply, Map.put(state, key, value)}
			end

			def handle_call({:get, key, default}, _from, state) do
				{:reply, Map.get(state, key, default), state}
			end

			def handle_call({:has, key}, _from, state) do
				{:reply, Map.has_key?(state, key), state}
			end

			def handle_call({:pop, key, default}, _from, state) do
				{value, new_state} = Map.pop(state, key, default)
				{:reply, value, new_state}
			end

			def get(key, default \\\\ nil) do
				Distributed.Scaler.GenServer.call(__MODULE__.process_id(), {:get, key, default})
			end

			def set(key, value) do
				{_node_name, result} = Distributed.Replicator.GenServer.cast(__MODULE__.process_id(), {:set, key, value})
					|> List.first()
				result
			end

			def has?(key) do
				Distributed.Scaler.GenServer.call(__MODULE__.process_id(), {:has, key})
			end

			def pop(key, default \\\\ nil) do
				{_node_name, result} = Distributed.Replicator.GenServer.call(__MODULE__.process_id(), {:pop, key, default})
					|> List.first()
				result
			end

		end

	You can see the example as a small project on [GitHub](https://github.com/ertgl/storage).


	### Installation:

	If [you have Hex](https://hex.pm), the package can be installed
	by adding `:distributed` to your list of dependencies in `mix.exs`:

		def application do
			[
				extra_applications: [
					:distributed,
				],
			]
		end

		def deps do
			[
				{:distributed, "~> 0.1.3"},
			]
		end
	"""

	defmacro __using__(opts \\ []) do
		scaler_opts = Keyword.get(opts, :scaler, [])
		replicator_opts = Keyword.get(opts, :replicator, [])

		quote do
			use Distributed.Scaler, unquote(scaler_opts)
			use Distributed.Replicator, unquote(replicator_opts)
		end
	end

end