simple elixir gproc pub/sub example for blog post

gproc_pubsub.ex

# supervisor.ex
defmodule EventSup do
  use Supervisor

  def start_link, do: Supervisor.start_link(__MODULE__, [], [])

  def init(_) do
    supervise(
      [
        worker(EventHandler, [:event_manager])
      ],
      [strategy: :one_for_one]
    )
  end
end

# event_handler.ex
defmodule EventHandler do
  use GenServer
  require Logger

  def start_link(topic), do: GenServer.start_link(__MODULE__, topic, [])

  def init(topic) do
    :gproc.reg({:p, :l, topic})

    {:ok, topic}
  end

  def handle_info(msg, topic) do
    Logger.info "received message #{inspect msg}"

    {:noreply, topic}
  end
end

# send message
iex>:gproc.send({:p, :l, :event_manager}, {:message, "stuff"})