urlsafe_decode64.erl

-module (base64ex).

-export ([urlsafe_decode64/1, urlsafe_encode64/1]).

urlsafe_decode64(Str) ->
    Str2 = re:replace(Str, "-", "+", [global, {return,list}]),
    Str3 = re:replace(Str2, "_", "/", [global, {return,list}]),
    base64:decode(Str3).

urlsafe_encode64(Bin) ->
    Bin2 = base64:encode(Bin),
    Bin3 = re:replace(binary_to_list(Bin2), "\\+", "-", [global, {return,list}]),
    re:replace(Bin3, "/", "_", [global, {return,list}]).

% Decode base64, throwing a more intelligible exception if it fails.
decode_base64(Base64) ->
    try base64:decode(Base64)
    catch
        error:_ -> throw({invalidBase64, Base64})
    end.