I am trying to update a map before rendered as json, but it is not working this way.
defp login_reply({:ok, user}, conn) do
with nil <- user.image_url do
user = Map.get_and_update(user, :image_url, fn current_value ->
{current_value, "<svg>image</svg>"}
end)
conn
|> render("show.json", user: user)
end
end