Elixir Email Validation

Elixir Email Validation

  defmodule EmailValidator do
  
    # ensure that the email looks valid
    def validate_email(email) when is_binary(email) do
      case Regex.run(~r/^[\w.!#$%&’*+\-\/=?\^`{|}~]+@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*$/i, email) do
        nil ->
          {:error, "Invalid email"}
        [email] ->
          try do
            Regex.run(~r/(\w+)@([\w.]+)/, email) |> validate_email
          rescue
            _ -> {:error, "Invalid email"}
          end
      end
    end
  
    # check the email against a list of accepted domains, then make check if it is unique
    def validate_email([email, username, host]) do
      case host in Config.accepted_domains do
        true ->
          case find_by_email(email) do
              nil -> :ok
              _account -> :account
          end
        _ ->
          {:error, "Not an accepted domain."}
      end
    end
  end

You are including both lowercase and uppercase ranges and then adding case-insensitivity flag. One of them is unnecessary.

~r/^[A-Za-z0-9._%+-+']+@[A-Za-z0-9.-]+\.[A-Za-z]+$/ no more {2,4}

I think you want to escape your dash between the + characters in the first "section" of the regex:

~r/^[A-Za-z0-9._%+\-+']+@[A-Za-z0-9.-]+\.[A-Za-z]+$/