Elixir lunch & learn

pattern_matching.ex

case HTTPoison.get(url, headers) do

  {:ok, %HTTPoison.Response{status_code: 200, body: body}} ->
    case Poison.decode(body) do
      {:ok, decoded} -> {:ok, decoded}
      {:error, error} -> {:error, error}
    end
    
  {:ok, %HTTPoison.Response{status_code: status_code}} ->
    {:error, status_code}

  {:error, error} ->
    {:error, error}
    
end

pipe_operator.ex

def process_response_body(body) do
  body
  |> Poison.decode!
  |> Map.take(@expected_fields)
  |> Enum.map(fn({k, v}) -> {String.to_atom(k), v} end)
end