%% The MIT License %% Copyright (c) 2011 Alisdair Sullivan %% Permission is hereby granted, free of charge, to any person obtaining a copy %% of this software and associated documentation files (the "Software"), to deal %% in the Software without restriction, including without limitation the rights %% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell %% copies of the Software, and to permit persons to whom the Software is %% furnished to do so, subject to the following conditions: %% The above copyright notice and this permission notice shall be included in %% all copies or substantial portions of the Software. %% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR %% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, %% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE %% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER %% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, %% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN %% THE SOFTWARE. -module(jsx_encoder). -export([encoder/3]). -spec encoder(Handler::module(), State::any(), Opts::jsx:opts()) -> jsx:encoder(). encoder(Handler, State, Opts) -> fun(JSON) -> start( JSON, {Handler, Handler:init(State)}, jsx_utils:parse_opts(Opts) ) end. -include("jsx_opts.hrl"). -ifndef(error). -define(error(Args), erlang:error(badarg, Args) ). -endif. start(Term, {Handler, State}, Opts) -> Handler:handle_event(end_json, value(pre_encode(Term, Opts), {Handler, State}, Opts)). value(String, {Handler, State}, Opts) when is_binary(String) -> Handler:handle_event({string, clean_string(String, Opts)}, State); value(Float, {Handler, State}, _Opts) when is_float(Float) -> Handler:handle_event({float, Float}, State); value(Int, {Handler, State}, _Opts) when is_integer(Int) -> Handler:handle_event({integer, Int}, State); value(Literal, {Handler, State}, _Opts) when Literal == true; Literal == false; Literal == null -> Handler:handle_event({literal, Literal}, State); value([{}], {Handler, State}, _Opts) -> Handler:handle_event(end_object, Handler:handle_event(start_object, State)); value([], {Handler, State}, _Opts) -> Handler:handle_event(end_array, Handler:handle_event(start_array, State)); value([Tuple|_] = List, Handler, Opts) when is_tuple(Tuple) -> list_or_object(List, Handler, Opts); value(List, Handler, Opts) when is_list(List) -> list_or_object(List, Handler, Opts); value(Term, Handler, Opts) -> ?error([Term, Handler, Opts]). list_or_object([Term|Rest], {Handler, State}, Opts) -> case pre_encode(Term, Opts) of {K, V} -> object([{K, V}|Rest], {Handler, Handler:handle_event(start_object, State)}, Opts) ; T -> list([T|Rest], {Handler, Handler:handle_event(start_array, State)}, Opts) end. object([{Key, Value}, Next|Rest], {Handler, State}, Opts) when is_atom(Key); is_binary(Key) -> V = pre_encode(Value, Opts), object( [pre_encode(Next, Opts)|Rest], { Handler, value( V, {Handler, Handler:handle_event({key, clean_string(fix_key(Key), Opts)}, State)}, Opts ) }, Opts ); object([{Key, Value}], {Handler, State}, Opts) when is_atom(Key); is_binary(Key) -> object( [], { Handler, value( pre_encode(Value, Opts), {Handler, Handler:handle_event({key, clean_string(fix_key(Key), Opts)}, State)}, Opts ) }, Opts ); object([], {Handler, State}, _Opts) -> Handler:handle_event(end_object, State); object(Term, Handler, Opts) -> ?error([Term, Handler, Opts]). list([Value, Next|Rest], {Handler, State}, Opts) -> list([pre_encode(Next, Opts)|Rest], {Handler, value(Value, {Handler, State}, Opts)}, Opts); list([Value], {Handler, State}, Opts) -> list([], {Handler, value(Value, {Handler, State}, Opts)}, Opts); list([], {Handler, State}, _Opts) -> Handler:handle_event(end_array, State); list(Term, Handler, Opts) -> ?error([Term, Handler, Opts]). pre_encode(Value, #opts{pre_encode=false}) -> Value; pre_encode(Value, Opts) -> (Opts#opts.pre_encode)(Value). fix_key(Key) when is_atom(Key) -> fix_key(atom_to_binary(Key, utf8)); fix_key(Key) when is_binary(Key) -> Key. clean_string(Bin, Opts) -> jsx_utils:clean_string(Bin, Opts). -ifdef(TEST). -include_lib("eunit/include/eunit.hrl"). encode(Term) -> encode(Term, []). encode(Term, Opts) -> try (encoder(jsx, [], Opts))(Term) catch _:_ -> {error, badarg} end. encode_test_() -> [ {"naked string", ?_assertEqual(encode(<<"a string\n">>), [{string, <<"a string\n">>}, end_json])}, {"escaped naked string", ?_assertEqual(encode(<<"a string\n">>, [escaped_strings]), [{string, <<"a string\\n">>}, end_json])}, {"naked integer", ?_assertEqual(encode(123), [{integer, 123}, end_json])}, {"naked float", ?_assertEqual(encode(1.23), [{float, 1.23}, end_json])}, {"naked literal", ?_assertEqual(encode(null), [{literal, null}, end_json])}, {"empty object", ?_assertEqual(encode([{}]), [start_object, end_object, end_json])}, {"empty list", ?_assertEqual(encode([]), [start_array, end_array, end_json])}, {"simple list", ?_assertEqual( encode([1,2,3,true,false]), [ start_array, {integer, 1}, {integer, 2}, {integer, 3}, {literal, true}, {literal, false}, end_array, end_json ] ) }, {"simple object", ?_assertEqual( encode([{<<"a">>, true}, {<<"b">>, false}]), [ start_object, {key, <<"a">>}, {literal, true}, {key, <<"b">>}, {literal, false}, end_object, end_json ] ) }, {"complex term", ?_assertEqual( encode([ {<<"a">>, true}, {<<"b">>, false}, {<<"c">>, [1,2,3]}, {<<"d">>, [{<<"key">>, <<"value">>}]} ]), [ start_object, {key, <<"a">>}, {literal, true}, {key, <<"b">>}, {literal, false}, {key, <<"c">>}, start_array, {integer, 1}, {integer, 2}, {integer, 3}, end_array, {key, <<"d">>}, start_object, {key, <<"key">>}, {string, <<"value">>}, end_object, end_object, end_json ] ) }, {"atom keys", ?_assertEqual( encode([{key, <<"value">>}]), [start_object, {key, <<"key">>}, {string, <<"value">>}, end_object, end_json] ) } ]. pre_encoders_test_() -> Term = [ {<<"object">>, [ {<<"literals">>, [true, false, null]}, {<<"strings">>, [<<"foo">>, <<"bar">>, <<"baz">>]}, {<<"numbers">>, [1, 1.0, 1.0e0]} ]} ], [ {"no pre encode", ?_assertEqual( encode(Term, []), [ start_object, {key, <<"object">>}, start_object, {key, <<"literals">>}, start_array, {literal, true}, {literal, false}, {literal, null}, end_array, {key, <<"strings">>}, start_array, {string, <<"foo">>}, {string, <<"bar">>}, {string, <<"baz">>}, end_array, {key, <<"numbers">>}, start_array, {integer, 1}, {float, 1.0}, {float, 1.0}, end_array, end_object, end_object, end_json ] )}, {"replace lists with empty lists", ?_assertEqual( encode(Term, [{pre_encode, fun(V) -> case V of [{_,_}|_] -> V; [{}] -> V; V when is_list(V) -> []; _ -> V end end}]), [ start_object, {key, <<"object">>}, start_object, {key, <<"literals">>}, start_array, end_array, {key, <<"strings">>}, start_array, end_array, {key, <<"numbers">>}, start_array, end_array, end_object, end_object, end_json ] )}, {"replace objects with empty objects", ?_assertEqual( encode(Term, [{pre_encode, fun(V) -> case V of [{_,_}|_] -> [{}]; _ -> V end end}]), [ start_object, end_object, end_json ] )}, {"replace all non-list and non_tuple values with false", ?_assertEqual( encode(Term, [{pre_encode, fun(V) when is_list(V); is_tuple(V) -> V; (_) -> false end}]), [ start_object, {key, <<"object">>}, start_object, {key, <<"literals">>}, start_array, {literal, false}, {literal, false}, {literal, false}, end_array, {key, <<"strings">>}, start_array, {literal, false}, {literal, false}, {literal, false}, end_array, {key, <<"numbers">>}, start_array, {literal, false}, {literal, false}, {literal, false}, end_array, end_object, end_object, end_json ] )}, {"replace all atoms with atom_to_list", ?_assertEqual( encode(Term, [{pre_encode, fun(V) when is_atom(V) -> unicode:characters_to_binary(atom_to_list(V)); (V) -> V end}]), [ start_object, {key, <<"object">>}, start_object, {key, <<"literals">>}, start_array, {string, <<"true">>}, {string, <<"false">>}, {string, <<"null">>}, end_array, {key, <<"strings">>}, start_array, {string, <<"foo">>}, {string, <<"bar">>}, {string, <<"baz">>}, end_array, {key, <<"numbers">>}, start_array, {integer, 1}, {float, 1.0}, {float, 1.0}, end_array, end_object, end_object, end_json ] )}, {"pre_encode tuple", ?_assertEqual( encode({1, 2, 3}, [{pre_encode, fun(Tuple) when is_tuple(Tuple) -> tuple_to_list(Tuple); (V) -> V end}]), [ start_array, {integer, 1}, {integer, 2}, {integer, 3}, end_array, end_json ] )}, {"pre_encode 2-tuples", ?_assertEqual( encode([{two, 1}, {three, 2}], [{pre_encode, fun({K, V}) -> {K, V + 1}; (V) -> V end}]), [ start_object, {key, <<"two">>}, {integer, 2}, {key, <<"three">>}, {integer, 3}, end_object, end_json ] )}, {"pre_encode one field record", ?_assertEqual( encode([{foo, bar}], [{pre_encode, fun({foo, V}) -> {V, undefined}; (undefined) -> false; (V) -> V end}]), [ start_object, {key, <<"bar">>}, {literal, false}, end_object, end_json ] )}, {"pre_encode list", ?_assertEqual( encode([1,2,3], [{pre_encode, fun(X) when is_integer(X) -> X + 1; (V) -> V end}]), [ start_array, {integer, 2}, {integer, 3}, {integer, 4}, end_array, end_json ] )} ]. -endif.