Run Oban and schedule jobs in not booted system

Questions / Help
1

I am trying to use Oban to queue jobs that send emails from a code that is run with eval "MySystem.Tasks.schedule_emails()". I do not have the system booted and trying to start Oban manual.
My code is something like

defmodule MySystem.Tasks do
  def schedule_emails do
     Ecto.Migrator.with_repo(MySystem.Repo, fn repo ->
        Application.ensure_all_started(:oban)
        config = Keyword.put(Application.fetch_env!(:my_system, Oban), :repo, repo)
        Supervisor.start_child(Oban.Registry, {Oban, config})

        do_schedule_emails()
     end)
  end

  defp do_schedule_emails do
    ...
    Oban.insert(SendEmailWorker.new(params))
  end
end

My question is if that is the correct way of starting the Oban.Registry and the Oban application?

2

The Oban registry is an internal detail and you don’t need to start children in it. Instead, you should use Oban.start_link:

Ecto.Migrator.with_repo(MySystem.Repo, fn repo ->
  Application.ensure_all_started(:oban)

  :my_system
  |> Application.fetch_env!(Oban)
  |> Keyword.put(:repo, repo)
  |> Oban.start_link()

  do_schedule_emails()
end)

Alternatively, if you’re only inserting emails without uniqueness, then you can use Repo.insert instead of Oban.insert and avoid starting Oban altogether.

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