%%%----------------------------------------------------------------------
%%% File : translate.erl
%%% Author : Alexey Shchepin <alexey@process-one.net>
%%% Purpose : Localization helper
%%% Created : 6 Jan 2003 by Alexey Shchepin <alexey@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2021 ProcessOne
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program is distributed in the hope that it will be useful,
%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License along
%%% with this program; if not, write to the Free Software Foundation, Inc.,
%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
%%%
%%%----------------------------------------------------------------------
-module(translate).
-author('alexey@process-one.net').
-behaviour(gen_server).
-export([start_link/0, reload/0, translate/2]).
%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
terminate/2, code_change/3]).
-include("logger.hrl").
-include_lib("kernel/include/file.hrl").
-define(ZERO_DATETIME, {{0,0,0}, {0,0,0}}).
-type error_reason() :: file:posix() | {integer(), module(), term()} |
badarg | terminated | system_limit | bad_file |
bad_encoding.
-record(state, {}).
start_link() ->
gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
init([]) ->
process_flag(trap_exit, true),
case load() of
ok ->
xmpp:set_tr_callback({?MODULE, translate}),
{ok, #state{}};
{error, Reason} ->
{stop, Reason}
end.
handle_call(Request, From, State) ->
?WARNING_MSG("Unexpected call from ~p: ~p", [From, Request]),
{noreply, State}.
handle_cast(Msg, State) ->
?WARNING_MSG("Unexpected cast: ~p", [Msg]),
{noreply, State}.
handle_info(Info, State) ->
?WARNING_MSG("Unexpected info: ~p", [Info]),
{noreply, State}.
terminate(_Reason, _State) ->
xmpp:set_tr_callback(undefined).
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
-spec reload() -> ok | {error, error_reason()}.
reload() ->
load(true).
-spec load() -> ok | {error, error_reason()}.
load() ->
load(false).
-spec load(boolean()) -> ok | {error, error_reason()}.
load(ForceCacheRebuild) ->
{MsgsDirMTime, MsgsDir} = get_msg_dir(),
{CacheMTime, CacheFile} = get_cache_file(),
{FilesMTime, MsgFiles} = get_msg_files(MsgsDir),
LastModified = lists:max([MsgsDirMTime, FilesMTime]),
if ForceCacheRebuild orelse CacheMTime < LastModified ->
case load(MsgFiles, MsgsDir) of
ok -> dump_to_file(CacheFile);
Err -> Err
end;
true ->
case ets:file2tab(CacheFile) of
{ok, _} ->
ok;
{error, {read_error, {file_error, _, enoent}}} ->
load(MsgFiles, MsgsDir);
{error, {read_error, {file_error, _, Reason}}} ->
?WARNING_MSG("Failed to read translation cache from ~ts: ~ts",
[CacheFile, format_error(Reason)]),
load(MsgFiles, MsgsDir);
{error, Reason} ->
?WARNING_MSG("Failed to read translation cache from ~ts: ~p",
[CacheFile, Reason]),
load(MsgFiles, MsgsDir)
end
end.
-spec load([file:filename()], file:filename()) -> ok | {error, error_reason()}.
load(Files, Dir) ->
try ets:new(translations, [named_table, public]) of
_ -> ok
catch _:badarg -> ok
end,
case Files of
[] ->
?WARNING_MSG("No translation files found in ~ts, "
"check directory access",
[Dir]);
_ ->
?INFO_MSG("Building language translation cache", []),
Objs = lists:flatten(misc:pmap(fun load_file/1, Files)),
case lists:keyfind(error, 1, Objs) of
false ->
ets:delete_all_objects(translations),
ets:insert(translations, Objs),
?DEBUG("Language translation cache built successfully", []);
{error, File, Reason} ->
?ERROR_MSG("Failed to read translation file ~ts: ~ts",
[File, format_error(Reason)]),
{error, Reason}
end
end.
-spec load_file(file:filename()) -> [{{binary(), binary()}, binary()} |
{error, file:filename(), error_reason()}].
load_file(File) ->
Lang = lang_of_file(File),
try file:consult(File) of
{ok, Lines} ->
lists:map(
fun({In, Out}) ->
try {unicode:characters_to_binary(In),
unicode:characters_to_binary(Out)} of
{InB, OutB} when is_binary(InB), is_binary(OutB) ->
{{Lang, InB}, OutB};
_ ->
{error, File, bad_encoding}
catch _:badarg ->
{error, File, bad_encoding}
end;
(_) ->
{error, File, bad_file}
end, Lines);
{error, Reason} ->
[{error, File, Reason}]
catch _:{case_clause, {error, _}} ->
%% At the moment of the writing there was a bug in
%% file:consult_stream/3 - it doesn't process {error, term()}
%% result from io:read/3
[{error, File, bad_file}]
end.
-spec translate(binary(), binary()) -> binary().
translate(Lang, Msg) ->
LLang = ascii_tolower(Lang),
case ets:lookup(translations, {LLang, Msg}) of
[{_, Trans}] -> Trans;
_ ->
ShortLang = case str:tokens(LLang, <<"-">>) of
[] -> LLang;
[SL | _] -> SL
end,
case ShortLang of
<<"en">> -> Msg;
LLang -> translate(Msg);
_ ->
case ets:lookup(translations, {ShortLang, Msg}) of
[{_, Trans}] -> Trans;
_ -> translate(Msg)
end
end
end.
-spec translate(binary()) -> binary().
translate(Msg) ->
case ejabberd_option:language() of
<<"en">> -> Msg;
Lang ->
LLang = ascii_tolower(Lang),
case ets:lookup(translations, {LLang, Msg}) of
[{_, Trans}] -> Trans;
_ ->
ShortLang = case str:tokens(LLang, <<"-">>) of
[] -> LLang;
[SL | _] -> SL
end,
case ShortLang of
<<"en">> -> Msg;
Lang -> Msg;
_ ->
case ets:lookup(translations, {ShortLang, Msg}) of
[{_, Trans}] -> Trans;
_ -> Msg
end
end
end
end.
-spec ascii_tolower(list() | binary()) -> binary().
ascii_tolower(B) when is_binary(B) ->
<< <<(if X >= $A, X =< $Z ->
X + 32;
true ->
X
end)>> || <<X>> <= B >>;
ascii_tolower(S) ->
ascii_tolower(unicode:characters_to_binary(S)).
-spec get_msg_dir() -> {calendar:datetime(), file:filename()}.
get_msg_dir() ->
Dir = misc:msgs_dir(),
case file:read_file_info(Dir) of
{ok, #file_info{mtime = MTime}} ->
{MTime, Dir};
{error, Reason} ->
?ERROR_MSG("Failed to read directory ~ts: ~ts",
[Dir, format_error(Reason)]),
{?ZERO_DATETIME, Dir}
end.
-spec get_msg_files(file:filename()) -> {calendar:datetime(), [file:filename()]}.
get_msg_files(MsgsDir) ->
Res = filelib:fold_files(
MsgsDir, ".+\\.msg", false,
fun(File, {MTime, Files} = Acc) ->
case xmpp_lang:is_valid(lang_of_file(File)) of
true ->
case file:read_file_info(File) of
{ok, #file_info{mtime = Time}} ->
{lists:max([MTime, Time]), [File|Files]};
{error, Reason} ->
?ERROR_MSG("Failed to read translation file ~ts: ~ts",
[File, format_error(Reason)]),
Acc
end;
false ->
?WARNING_MSG("Ignoring translation file ~ts: file name "
"must be a valid language tag",
[File]),
Acc
end
end, {?ZERO_DATETIME, []}),
case Res of
{_, []} ->
case file:list_dir(MsgsDir) of
{ok, _} -> ok;
{error, Reason} ->
?ERROR_MSG("Failed to read directory ~ts: ~ts",
[MsgsDir, format_error(Reason)])
end;
_ ->
ok
end,
Res.
-spec get_cache_file() -> {calendar:datetime(), file:filename()}.
get_cache_file() ->
MnesiaDir = mnesia:system_info(directory),
CacheFile = filename:join(MnesiaDir, "translations.cache"),
CacheMTime = case file:read_file_info(CacheFile) of
{ok, #file_info{mtime = Time}} -> Time;
{error, _} -> ?ZERO_DATETIME
end,
{CacheMTime, CacheFile}.
-spec dump_to_file(file:filename()) -> ok.
dump_to_file(CacheFile) ->
case ets:tab2file(translations, CacheFile) of
ok -> ok;
{error, Reason} ->
?WARNING_MSG("Failed to create translation cache in ~ts: ~p",
[CacheFile, Reason])
end.
-spec lang_of_file(file:filename()) -> binary().
lang_of_file(FileName) ->
BaseName = filename:basename(FileName),
ascii_tolower(filename:rootname(BaseName)).
-spec format_error(error_reason()) -> string().
format_error(bad_file) ->
"corrupted or invalid translation file";
format_error(bad_encoding) ->
"cannot translate from UTF-8";
format_error({_, _, _} = Reason) ->
"at line " ++ file:format_error(Reason);
format_error(Reason) ->
file:format_error(Reason).
