Race condition using broadway with Mongo multi-tenant

Questions / Help
,
1

Hello everyone!

I’m new to Elixir and I’m trying to use broadway with Mongo multi-tenant.

Every time I get a different host, I need to open a connection to Mongo, but I notice that I have more than one connection per host.

Before opening the connection, I validate if the process has started, but I’m not sure if it’s correct.

defmodule CoreConsumer.Shared.Mongo.Tenant do
  use DynamicSupervisor

  require Logger

  alias FE.Result
  alias CoreConsumer.Shared.Mongo

  def start_link(_arg) do
    DynamicSupervisor.start_link(__MODULE__, :ok, name: __MODULE__)
  end

  def init(:ok) do
    DynamicSupervisor.init(strategy: :one_for_one)
  end

  def start_connection(host) do
    case  Process.whereis(:"#{host}") do
      nil ->
        DynamicSupervisor.start_child(__MODULE__, %{
          id: host,
          type: :worker,
          restart: :transient,
          start: {Mongo, :start_link, [[host: host]]}
        })
      pid ->
        Result.ok(pid)
    end
  end
end