Controller.ex

  def create(conn, %{"stress" => stress_params}) do
    changeset = Stress.changeset(%Stress{}, stress_params)
    IO.inspect stress_params
    {long, lat, type} = {stress_params["long"], stress_params["lat"], stress_params["type"]}
    q = from p in Plataforma.Average,
        select: p,
        where: p.long == ^long and p.lat == ^lat and p.type == ^type
    average = Repo.all(q) |> first_or_create
    average_params = %Plataforma.Average{"long" => stress_params["long"],
                       "lat" => stress_params["lat"],
                       "type" => stress_params["type"],
                       "stress" => average[:stress] * (average[:samples]) / (average[:samples] + 1) + stress_params["stress"] / (average[:samples] + 1),
                       "samples" => average[:samples] + 1}
    average_cs = Average.changeset(average, average_params)
    case Repo.insert(changeset) do
      {:ok, stress} ->
        Repo.insert(average_cs)
        conn
        |> put_status(:created)
        |> put_resp_header("location", stress_path(conn, :show, stress))
        |> render("show.json", stress: stress)
      {:error, changeset} ->
        conn
        |> put_status(:unprocessable_entity)
        |> render(Plataforma.ChangesetView, "error.json", changeset: changeset)
    end
  end
  
  defp first_or_create([]) do %Plataforma.Average{stress: 0.5, samples: 0} end
  defp first_or_create([x|_]) do x end
  
  

error.log

== Compilation error on file web/controllers/stress_controller.ex ==
** (CompileError) web/controllers/stress_controller.ex:21: unknown key "long" for struct Plataforma.Average
    (elixir) src/elixir_map.erl:182: :elixir_map."-assert_struct_keys/5-lc$^0/1-0-"/5
    (elixir) src/elixir_map.erl:59: :elixir_map.translate_struct/4
    (elixir) src/elixir_clauses.erl:36: :elixir_clauses.clause/7
    (elixir) src/elixir_def.erl:178: :elixir_def.translate_clause/7
    (elixir) src/elixir_def.erl:167: :elixir_def.translate_definition/8
    (elixir) src/elixir_def.erl:82: :elixir_def.store_definition/9
    web/controllers/stress_controller.ex:13: (module)
    (stdlib) erl_eval.erl:657: :erl_eval.do_apply/6