Ecto 2 Allowances for TestingAdapter

[nathany]

When upgraded a Phoenix project to Ecto 2.0-beta.2 we see the following error in our mailer tests:

** (RuntimeError) cannot find ownership process

There are two solutions to this issue, as documented in Ecto.Adapters.SQL.Sandbox.

For now we're using Shared mode, which works but runs the mailer tests synchronously. To have all the tests run concurrently, we could use Allowances in TestingAdapter:

defmodule Mailman.TestingAdapter do
  @moduledoc "Implementation of the testing SMTP adapter"

  def deliver(config, _email, message) do
    parent = self() # PID of the parent process
    Task.async fn ->
      Ecto.Adapters.SQL.Sandbox.allow(TestRepo, parent, self()) # need MyApp.Repo
      if config.store_deliveries do
        Mailman.TestServer.register_delivery message
      end
      { :ok, message }
    end
  end

end

We've tested this out, but with the name of our Repo hard coded. Do you think it would be possible to get this working?

[keichan34]

Similar situation -- I'm working on making more of my tests async and Ecto 2.0. I'm currently using solutions in my PRs #44 and #45:

• Refactor Mailman.Context to allow for explicit config structs #44 for a MyApp.TestingAdapter that has similar contents to what you have there, with the Repo hardcoded in. My rationale for not patching Mailman for this was because Mailman should not be dependent on Ecto.
• Independent TestServer per calling process #45 for the actual async tests not interfering with each other

[nathany]

Thanks.

I agree it makes sense to not depend on Ecto. Does using independent test processes have any significant impact on how quickly tests run?

[keichan34]

In my case, it's speeding tests up because the central TestServer was the bottleneck when doing a bunch of mailer tests in parallel.

[nathany]

Very nice. Thanks a bunch.

I'm gonna close this issue since you're obviously on top of it.