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Diffstat (limited to 'src/rebar_mustache.erl')
| -rw-r--r-- | src/rebar_mustache.erl | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/src/rebar_mustache.erl b/src/rebar_mustache.erl new file mode 100644 index 0000000..af8a342 --- /dev/null +++ b/src/rebar_mustache.erl @@ -0,0 +1,296 @@ +%% The MIT License (MIT) +%% +%% Copyright (c) 2015 Hinagiku Soranoba +%% +%% 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. +%% +%% @doc Mustache template engine for Erlang/OTP. +-module(rebar_mustache). + +%%---------------------------------------------------------------------------------------------------------------------- +%% Exported API +%%---------------------------------------------------------------------------------------------------------------------- +-export([ + render/2, + parse_binary/1, + parse_file/1, + compile/2 + ]). + +-export_type([ + template/0, + data/0 + ]). + +%%---------------------------------------------------------------------------------------------------------------------- +%% Defines & Records & Types +%%---------------------------------------------------------------------------------------------------------------------- + +-define(PARSE_ERROR, incorrect_format). +-define(FILE_ERROR, file_not_found). +-define(COND(Cond, TValue, FValue), + case Cond of true -> TValue; false -> FValue end). + +-type key() :: binary(). +-type tag() :: {n, key()} | + {'&', key()} | + {'#', key(), [tag()], Source :: binary()} | + {'^', key(), [tag()]} | + binary(). + +-record(state, + { + dirname = <<>> :: file:filename_all(), + start = <<"{{">> :: binary(), + stop = <<"}}">> :: binary() + }). +-type state() :: #state{}. + +-record(?MODULE, + { + data :: [tag()] + }). + +-opaque template() :: #?MODULE{}. +%% @see parse_binary/1 +%% @see parse_file/1 +-ifdef(namespaced_types). +-type data() :: #{string() => data() | iodata() | fun((data(), function()) -> iodata())}. +-else. +-type data() :: dict(). +-endif. +%% @see render/2 +%% @see compile/2 +-type partial() :: {partial, {state(), EndTag :: binary(), LastTagSize :: non_neg_integer(), Rest :: binary(), [tag()]}}. + +%%---------------------------------------------------------------------------------------------------------------------- +%% Exported Functions +%%---------------------------------------------------------------------------------------------------------------------- + +%% @equiv compile(parse_binary(Bin), Map) +-spec render(binary(), data()) -> binary(). +render(Bin, Map) -> + compile(parse_binary(Bin), Map). + +%% @doc Create a {@link template/0} from a binary. +-spec parse_binary(binary()) -> template(). +parse_binary(Bin) when is_binary(Bin) -> + parse_binary_impl(#state{}, Bin). + +%% @doc Create a {@link template/0} from a file. +-spec parse_file(file:filename()) -> template(). +parse_file(Filename) -> + case file:read_file(Filename) of + {ok, Bin} -> parse_binary_impl(#state{dirname = filename:dirname(Filename)}, Bin); + _ -> error(?FILE_ERROR, [Filename]) + end. + +%% @doc Embed the data in the template. +-spec compile(template(), data()) -> binary(). +compile(#?MODULE{data = Tags}, Map) -> + ec_cnv:to_binary(lists:reverse(compile_impl(Tags, Map, []))). + +%%---------------------------------------------------------------------------------------------------------------------- +%% Internal Function +%%---------------------------------------------------------------------------------------------------------------------- + +%% @doc {@link compile/2} +%% +%% ATTENTION: The result is a list that is inverted. +-spec compile_impl(Template :: [tag()], data(), Result :: iodata()) -> iodata(). +compile_impl([], _, Result) -> + Result; +compile_impl([{n, Key} | T], Map, Result) -> + compile_impl(T, Map, [escape(to_binary(dict_get(binary_to_list(Key), Map, <<>>))) | Result]); +compile_impl([{'&', Key} | T], Map, Result) -> + compile_impl(T, Map, [to_binary(dict_get(binary_to_list(Key), Map, <<>>)) | Result]); +compile_impl([{'#', Key, Tags, Source} | T], Map, Result) -> + Value = dict_get(binary_to_list(Key), Map, undefined), + if + is_list(Value) -> compile_impl(T, Map, lists:foldl(fun(X, Acc) -> compile_impl(Tags, X, Acc) end, + Result, Value)); + Value =:= false; Value =:= undefined -> compile_impl(T, Map, Result); + is_function(Value, 2) -> compile_impl(T, Map, [Value(Source, fun(Text) -> render(Text, Map) end) | Result]); + %is_dict(Value) -> compile_impl(T, Map, compile_impl(Tags, Value, Result)); + true -> compile_impl(T, Map, compile_impl(Tags, Map, Result)) + end; +compile_impl([{'^', Key, Tags} | T], Map, Result) -> + Value = dict_get(binary_to_list(Key), Map, undefined), + case Value =:= undefined orelse Value =:= [] orelse Value =:= false of + true -> compile_impl(T, Map, compile_impl(Tags, Map, Result)); + false -> compile_impl(T, Map, Result) + end; +compile_impl([Bin | T], Map, Result) -> + compile_impl(T, Map, [Bin | Result]). + +%% @see parse_binary/1 +-spec parse_binary_impl(state(), Input :: binary()) -> template(). +parse_binary_impl(State, Input) -> + #?MODULE{data = parse(State, Input)}. + +%% @doc Analyze the syntax of the mustache. +-spec parse(state(), binary()) -> [tag()]. +parse(State, Bin) -> + case parse1(State, Bin, []) of + {partial, _} -> error(?PARSE_ERROR); + {_, Tags} -> lists:reverse(Tags) + end. + +%% @doc Part of the `parse/1' +%% +%% ATTENTION: The result is a list that is inverted. +-spec parse1(state(), Input :: binary(), Result :: [tag()]) -> {state(), [tag()]} | partial(). +parse1(#state{start = Start, stop = Stop} = State, Bin, Result) -> + case binary:split(Bin, Start) of + [] -> {State, Result}; + [B1] -> {State, [B1 | Result]}; + [B1, <<"{", B2/binary>>] -> parse2(State, binary:split(B2, <<"}", Stop/binary>>), [B1 | Result]); + [B1, B2] -> parse3(State, binary:split(B2, Stop), [B1 | Result]) + end. + +%% @doc Part of the `parse/1' +%% +%% ATTENTION: The result is a list that is inverted. +parse2(State, [B1, B2], Result) -> + parse1(State, B2, [{'&', remove_space_from_edge(B1)} | Result]); +parse2(_, _, _) -> + error(?PARSE_ERROR). + +%% @doc Part of the `parse/1' +%% +%% ATTENTION: The result is a list that is inverted. +parse3(State, [B1, B2], Result) -> + case remove_space_from_head(B1) of + <<"&", Tag/binary>> -> + parse1(State, B2, [{'&', remove_space_from_edge(Tag)} | Result]); + <<T, Tag/binary>> when T =:= $#; T =:= $^ -> + parse_loop(State, ?COND(T =:= $#, '#', '^'), remove_space_from_edge(Tag), B2, Result); + <<"=", Tag0/binary>> -> + Tag1 = remove_space_from_tail(Tag0), + Size = byte_size(Tag1) - 1, + case Size >= 0 andalso Tag1 of + <<Tag2:Size/binary, "=">> -> parse_delimiter(State, Tag2, B2, Result); + _ -> error(?PARSE_ERROR) + end; + <<"!", _/binary>> -> + parse1(State, B2, Result); + <<"/", Tag/binary>> -> + {partial, {State, remove_space_from_edge(Tag), byte_size(B1) + 4, B2, Result}}; + <<">", Tag/binary>> -> + parse_jump(State, remove_space_from_edge(Tag), B2, Result); + Tag -> + parse1(State, B2, [{n, remove_space_from_tail(Tag)} | Result]) + end; +parse3(_, _, _) -> + error(?PARSE_ERROR). + +%% @doc Loop processing part of the `parse/1' +%% +%% `{{# Tag}}' or `{{^ Tag}}' corresponds to this. +-spec parse_loop(state(), '#' | '^', Tag :: binary(), Input :: binary(), Result :: [tag()]) -> [tag()] | partial(). +parse_loop(State0, Mark, Tag, Input, Result0) -> + case parse1(State0, Input, []) of + {partial, {State, Tag, LastTagSize, Rest, Result1}} when is_list(Result1) -> + case Mark of + '#' -> Source = binary:part(Input, 0, byte_size(Input) - byte_size(Rest) - LastTagSize), + parse1(State, Rest, [{'#', Tag, lists:reverse(Result1), Source} | Result0]); + '^' -> parse1(State, Rest, [{'^', Tag, lists:reverse(Result1)} | Result0]) + end; + _ -> + error(?PARSE_ERROR) + end. + +%% @doc Partial part of the `parse/1' +-spec parse_jump(state(), Tag :: binary(), NextBin :: binary(), Result :: [tag()]) -> [tag()] | partial(). +parse_jump(#state{dirname = Dirname} = State0, Tag, NextBin, Result0) -> + Filename0 = <<Tag/binary, ".mustache">>, + Filename = filename:join(?COND(Dirname =:= <<>>, [Filename0], [Dirname, Filename0])), + case file:read_file(Filename) of + {ok, Bin} -> + case parse1(State0, Bin, Result0) of + {partial, _} -> error(?PARSE_ERROR); + {State, Result} -> parse1(State, NextBin, Result) + end; + _ -> + error(?FILE_ERROR, [Filename]) + end. + +%% @doc Update delimiter part of the `parse/1' +%% +%% Parse_BinaryDelimiterBin :: e.g. `{{=%% %%=}}' -> `%% %%' +-spec parse_delimiter(state(), Parse_BinaryDelimiterBin :: binary(), NextBin :: binary(), Result :: [tag()]) -> [tag()] | partial(). +parse_delimiter(State0, Parse_BinaryDelimiterBin, NextBin, Result) -> + case binary:match(Parse_BinaryDelimiterBin, <<"=">>) of + nomatch -> + case [X || X <- binary:split(Parse_BinaryDelimiterBin, <<" ">>, [global]), X =/= <<>>] of + [Start, Stop] -> parse1(State0#state{start = Start, stop = Stop}, NextBin, Result); + _ -> error(?PARSE_ERROR) + end; + _ -> + error(?PARSE_ERROR) + end. + +%% @doc Remove the space from the edge. +-spec remove_space_from_edge(binary()) -> binary(). +remove_space_from_edge(Bin) -> + remove_space_from_tail(remove_space_from_head(Bin)). + +%% @doc Remove the space from the head. +-spec remove_space_from_head(binary()) -> binary(). +remove_space_from_head(<<" ", Rest/binary>>) -> remove_space_from_head(Rest); +remove_space_from_head(Bin) -> Bin. + +%% @doc Remove the space from the tail. +-spec remove_space_from_tail(binary()) -> binary(). +remove_space_from_tail(<<>>) -> <<>>; +remove_space_from_tail(Bin) -> + PosList = binary:matches(Bin, <<" ">>), + LastPos = remove_space_from_tail_impl(lists:reverse(PosList), byte_size(Bin)), + binary:part(Bin, 0, LastPos). + +%% @see remove_space_from_tail/1 +-spec remove_space_from_tail_impl([{non_neg_integer(), pos_integer()}], non_neg_integer()) -> non_neg_integer(). +remove_space_from_tail_impl([{X, Y} | T], Size) when Size =:= X + Y -> + remove_space_from_tail_impl(T, X); +remove_space_from_tail_impl(_, Size) -> + Size. + +%% @doc Number to binary +-spec to_binary(number() | binary() | string()) -> binary() | string(). +to_binary(Integer) when is_integer(Integer) -> + ec_cnv:to_binary(Integer); +to_binary(Float) when is_float(Float) -> + io_lib:format("~p", [Float]); +to_binary(X) -> + X. + +%% @doc HTML Escape +-spec escape(iodata()) -> binary(). +escape(IoData) -> + Bin = ec_cnv:to_binary(IoData), + << <<(escape_char(X))/binary>> || <<X:8>> <= Bin >>. + +%% @see escape/1 +-spec escape_char(0..16#FFFF) -> binary(). +escape_char($<) -> <<"<">>; +escape_char($>) -> <<">">>; +escape_char($&) -> <<"&">>; +escape_char($") -> <<""">>; +escape_char($') -> <<"'">>; +escape_char(C) -> <<C:8>>. + +dict_get(Key, Dict, Default) -> + case dict:find(ec_cnv:to_atom(Key), Dict) of + {ok, Value} -> + Value; + error -> + Default + end. |