jsx/src/jsx_encoder.erl

305 lines
No EOL
11 KiB
Erlang

%% The MIT License
%% Copyright (c) 2011 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
%% 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(), Config::jsx:config()) -> jsx:encoder().
encoder(Handler, State, Config) ->
fun(JSON) ->
start(
JSON,
{Handler, Handler:init(State)},
jsx_utils:parse_config(Config)
)
end.
-include("jsx_config.hrl").
-ifndef(error).
-define(error(State, Term, Handler, Config),
case Config#config.error_handler of
false -> erlang:error(badarg);
F -> erlang:throw(F(Term, {encoder, State, Handler}, jsx_utils:config_to_list(Config)))
end
).
-endif.
start(Term, {Handler, State}, Config) ->
try Handler:handle_event(end_json, value(pre_encode(Term, Config), {Handler, State}, Config))
catch
throw:Error -> Error;
Type:Value -> erlang:Type(Value)
end.
value(String, {Handler, State}, Config) when is_binary(String) ->
Handler:handle_event({string, clean_string(String, {Handler, State}, Config)}, State);
value(Float, {Handler, State}, _Config) when is_float(Float) ->
Handler:handle_event({float, Float}, State);
value(Int, {Handler, State}, _Config) when is_integer(Int) ->
Handler:handle_event({integer, Int}, State);
value(Literal, {Handler, State}, _Config)
when Literal == true; Literal == false; Literal == null ->
Handler:handle_event({literal, Literal}, State);
value([{}], {Handler, State}, _Config) ->
Handler:handle_event(end_object, Handler:handle_event(start_object, State));
value([], {Handler, State}, _Config) ->
Handler:handle_event(end_array, Handler:handle_event(start_array, State));
value([Tuple|_] = List, Handler, Config) when is_tuple(Tuple) ->
list_or_object(List, Handler, Config);
value(List, Handler, Config) when is_list(List) ->
list_or_object(List, Handler, Config);
value(Term, Handler, Config) -> ?error(value, Term, Handler, Config).
list_or_object([Term|Rest], {Handler, State}, Config) ->
case pre_encode(Term, Config) of
{K, V} when is_atom(K); is_binary(K) ->
object([{K, V}|Rest], {Handler, Handler:handle_event(start_object, State)}, Config)
; T ->
list([T|Rest], {Handler, Handler:handle_event(start_array, State)}, Config)
end.
object([{Key, Value}, Next|Rest], {Handler, State}, Config) when is_atom(Key); is_binary(Key) ->
V = pre_encode(Value, Config),
object(
[pre_encode(Next, Config)|Rest],
{
Handler,
value(
V,
{Handler, Handler:handle_event({key, clean_string(fix_key(Key), {Handler, State}, Config)}, State)},
Config
)
},
Config
);
object([{Key, Value}], {Handler, State}, Config) when is_atom(Key); is_binary(Key) ->
object(
[],
{
Handler,
value(
pre_encode(Value, Config),
{Handler, Handler:handle_event({key, clean_string(fix_key(Key), {Handler, State}, Config)}, State)},
Config
)
},
Config
);
object([], {Handler, State}, _Config) -> Handler:handle_event(end_object, State).
list([Value, Next|Rest], {Handler, State}, Config) ->
list([pre_encode(Next, Config)|Rest], {Handler, value(Value, {Handler, State}, Config)}, Config);
list([Value], {Handler, State}, Config) ->
list([], {Handler, value(Value, {Handler, State}, Config)}, Config);
list([], {Handler, State}, _Config) -> Handler:handle_event(end_array, State).
pre_encode(Value, #config{pre_encode=false}) -> Value;
pre_encode(Value, Config) -> (Config#config.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, Handler, Config) ->
try jsx_utils:clean_string(Bin, Config)
catch error:badarg -> ?error(string, Bin, Handler, Config)
end.
-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").
encode_test_() ->
Data = jsx:test_cases(),
[
{
Title, ?_assertEqual(
Events ++ [end_json],
start(Term, {jsx, []}, #config{})
)
} || {Title, _, Term, Events} <- Data
].
encode(Term, Config) -> start(Term, {jsx, []}, jsx_utils:parse_config(Config)).
pre_encoders_test_() ->
Term = [
{<<"object">>, [
{<<"literals">>, [true, false, null]},
{<<"strings">>, [<<"foo">>, <<"bar">>, <<"baz">>]},
{<<"numbers">>, [1, 1.0, 1.0e0]}
]}
],
[
{"no pre encode", ?_assertEqual(
[
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
],
encode(Term, [])
)},
{"replace lists with empty lists", ?_assertEqual(
[
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
],
encode(Term, [{pre_encode, fun(V) -> case V of [{_,_}|_] -> V; [{}] -> V; V when is_list(V) -> []; _ -> V end end}])
)},
{"replace objects with empty objects", ?_assertEqual(
[
start_object,
end_object,
end_json
],
encode(Term, [{pre_encode, fun(V) -> case V of [{_,_}|_] -> [{}]; _ -> V end end}])
)},
{"replace all non-list and non_tuple values with false", ?_assertEqual(
[
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
],
encode(Term, [{pre_encode, fun(V) when is_list(V); is_tuple(V) -> V; (_) -> false end}])
)},
{"replace all atoms with atom_to_list", ?_assertEqual(
[
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
],
encode(Term, [{pre_encode, fun(V) when is_atom(V) -> unicode:characters_to_binary(atom_to_list(V)); (V) -> V end}])
)},
{"pre_encode tuple", ?_assertEqual(
[
start_array,
{integer, 1}, {integer, 2}, {integer, 3},
end_array,
end_json
],
encode({1, 2, 3}, [{pre_encode, fun(Tuple) when is_tuple(Tuple) -> tuple_to_list(Tuple); (V) -> V end}])
)},
{"pre_encode 2-tuples", ?_assertEqual(
[
start_object,
{key, <<"two">>}, {integer, 2}, {key, <<"three">>}, {integer, 3},
end_object,
end_json
],
encode([{two, 1}, {three, 2}], [{pre_encode, fun({K, V}) -> {K, V + 1}; (V) -> V end}])
)},
{"pre_encode one field record", ?_assertEqual(
[
start_object,
{key, <<"bar">>}, {literal, false},
end_object,
end_json
],
encode([{foo, bar}], [{pre_encode, fun({foo, V}) -> {V, undefined}; (undefined) -> false; (V) -> V end}])
)},
{"pre_encode list", ?_assertEqual(
[
start_array,
{integer, 2}, {integer, 3}, {integer, 4},
end_array,
end_json
],
encode([1,2,3], [{pre_encode, fun(X) when is_integer(X) -> X + 1; (V) -> V end}])
)}
].
error_test_() ->
[
{"value error", ?_assertError(badarg, encode(self(), []))},
{"string error", ?_assertError(badarg, encode(<<16#ffff/utf8>>, []))}
].
custom_error_handler_test_() ->
Error = fun(Term, {_, State, _}, _) -> {State, Term} end,
[
{"value error", ?_assertEqual(
{value, self()},
encode(self(), [{error_handler, Error}])
)},
{"string error", ?_assertEqual(
{string, <<16#ffff/utf8>>},
encode(<<16#ffff/utf8>>, [{error_handler, Error}])
)}
].
-endif.