how to retry connect ampq in Elixir - rabbitmq

Question

I'm trying to connect to a RabbitMQ instance using the ampq package on Elixir, but at times the RabbitMQ instance won't be available at the time that the Elixir server is running. I was wondering how I might be able to implement a simple retry mechanism. There's one strategy here but that seems more involved than I feel necessary especially since there's a mention of it on the README about more information being found on the official docs. I unfortunately couldn't find anything.
Edit: This will crash the application on start and exit.
My code for the module is as follows:
Server.Gen.Rabbit (child)
defmodule Server.Gen.Rabbit do
use GenServer
use AMQP
defmodule State do
#type t :: %{
id: String.t(),
chan: map()
}
defstruct id: "", chan: nil
end
def start_link(%{id: id}) do
GenServer.start_link(
__MODULE__,
%State{
id: id
},
name: :"#{id}:rabbit"
)
end
def init(opts) do
host = "amqp://guest:guest#localhost"
case Connection.open(host) do
{:ok, conn} ->
{:ok, chan} = Channel.open(conn)
setup_queue(opts.id, chan)
:ok = Basic.qos(chan, prefetch_count: 1)
queue_to_consume = #online_receive_queue <> opts.id
IO.puts("queue_to_consume_online: " <> queue_to_consume)
{:ok, _consumer_tag} = Basic.consume(chan, queue_to_consume, nil, no_ack: true)
{:ok, %State{chan: chan, id: opts.id}}
{:error, _} ->
IO.puts("[Rabbit] error on connecting to server: #{host}")
{:backoff, 5_000}
end
end
Server (parent)
defmodule Server do
use Application
def start(_type, _args) do
import Supervisor.Spec, warn: false
children = [
{
GenRegistry,
worker_module: Server.Gen.Rabbit
},
Plug.Cowboy.child_spec(
scheme: :http,
plug: Server.Router,
options: [
port: String.to_integer(System.get_env("PORT") || "3000"),
dispatch: dispatch(),
protocol_options: [idle_timeout: :infinity]
]
)
]
opts = [strategy: :one_for_one, name: Server.Supervisor]
Supervisor.start_link(children, opts)
end
end