0nitro/src/nitro_conv.erl

-module(nitro_conv).
% N2Z Formatter: JSON, BERT
% author Maxim Sokhatsky

-include_lib("nitro/include/nitro.hrl").

-compile([export_all, nowarn_export_all]). % todo export

% JOIN

join([],_) -> [];
join([Item], _Delim) -> [Item];
join([Item|Items], Delim) -> [Item, Delim | join(Items,Delim)].


f(S) -> f(S, []).
f(S, Args) -> lists:flatten(io_lib:format(S, Args)).

replace([], _, _) -> [];
replace(String, S1, S2) when erlang:is_list(String), erlang:is_list(S1), erlang:is_list(S2) ->
  Length = erlang:length(S1),
  case string:substr(String, 1, Length) of
    S1 ->
      S2 ++ replace(string:substr(String, Length + 1), S1, S2);
    _ ->
      [erlang:hd(String)|replace(erlang:tl(String), S1, S2)]
  end.

coalesce({_, Y}) -> Y;
coalesce(false) -> undefined;
coalesce([]) -> undefined;
coalesce([H]) -> H;
coalesce([undefined|T]) -> coalesce(T);
coalesce([[]|T]) -> coalesce(T);
coalesce([H|_]) -> H.

indexof(Key, Fields) -> indexof(Key, Fields, 2).
indexof(_Key, [], _N) -> undefined;
indexof(Key, [Key|_T], N) -> N;
indexof(Key, [_|T], N) -> indexof(Key, T, N + 1).

config(App, Key, Default) ->
  application:get_env(App,Key,Default).

os_env(Key) -> os_env(Key, "").
os_env(Key, Default) ->
  case os:getenv(Key) of
    false -> Default;
    V -> V
  end.


% base64 encode/decode
pickle(Data) ->
  base64:encode(erlang:term_to_binary({Data, os:timestamp()}, [compressed])).

depickle(PickledData) ->
  try
    {Data, _PickleTime} = erlang:binary_to_term(base64:decode(nitro:to_binary(PickledData))),
    Data
  catch _:_ ->
    undefined
  end.