Zero trust configuration issues about livebook

[spunkedy]

working on a PR now for this if this is a real issue

[josevalim]

Yeah, a PR is welcome. We should probably return {:zta, module, info}.

[josevalim]

And I was the one who broke it, here: c9d0c05 :)

[spunkedy]

haha no worries, I am trying to find the best way to add the test coverage now.

[josevalim]

It is really hard because it happens on boot. A type system would have caught it. I think a unit test is fine for now.

[spunkedy]

Yeah, my plan was to allow for an override for the config function something like:

  def identity_provider!(env) do
    case get_system_env_or_test_provider(env) do
      nil ->
        {:session, LivebookWeb.SessionIdentity, :unused}

      "custom:" <> module_key ->
        destructure [module, key], String.split(module_key, ":", parts: 2)
        module = Module.concat([module])

        if Code.ensure_loaded?(module) do
          {:custom, module, key}
        else
          abort!("module given as custom identity provider in #{env} could not be found")
        end

      provider ->
        with [type, key] <- String.split(provider, ":", parts: 2),
             %{^type => module} <- identity_provider_type_to_module() do
          {nil, module, key}
        else
          _ -> abort!("invalid configuration for identity provider given in #{env}")
        end
    end
  end

  # Allow for this function to be tested more easily
  defp get_system_env_or_test_provider(env) do
    case {System.get_env(env), env} do
      {nil, "TEST_IDENTITY_" <> provider} -> provider
      {nil, _} -> nil
      {provider, _} -> provider
    end
  end

that would then allow us to check the contract, since the bug was in the application start of the pattern match