Hello all,

after some years working with elixir, there are still some situations I don’t know how to clearly resolve, thinking about putting together some best practices for ecto and other tools. To make it easy I decided to start project and simply document all issues I came along. Besides that I’m also trying a lot of stuff (using plug and ecto without phoenix, schemas folder instead of domain driven design style). So I’m asking here for opinion, maybe some constructive critics etc GitHub - tino415/authex: Simple API only OAuth2/OpenID server · GitHub. So far I stumble on these:

• I’m trying to follow CQRS and also to use changeset for most casting and validation
  but I think these things sometimes get in conflict. In this case I got to conflict
  when I was trying to validate creation of token. Because, in case o refresh token,
  I need casted refresh token from data to retrieve previous token to verify it validity,
  I resolved to what I always does, basically manually cast it in action (sort of controller)
  and pass selected token to changeset.

  Action:

  @impl true
  def create(conn, %{"code" => code} = params) do
    with %{} = flow <- Authex.get_flow_by_code_without_token(code) do
      do_create(conn, flow, params)
    else
      nil -> View.unauthorized(conn)
    end
  end
  
  def create(conn, %{"refresh_token" => refresh_token} = params) do
    with %{} = flow <- Authex.get_flow_by_refresh_token(refresh_token) do
      do_create(conn, flow, params)
    else
      nil -> View.unauthorized(conn)
    end
  end
  
  def create(conn, body_params) do
    do_create(conn, nil, body_params)
  end
  

• I always tried to use put_assoc so result after inserting contains that association and
  I don’t need to return associated entity separately, but in this project it does not
  work. So I have this line after updating token:

    |> case do
      {:ok, client} -> {:ok, Repo.preload(client, scopes: :scope)}
      r -> r
    end