Use banword instead of bloom + etbloom + bitarray (thanks to ytkang)

mod_pottymouth/README.txt

@@ -6,24 +6,6 @@ sizes. Using a large list (say, 87M terms) will slow down the initial server
 boot time (to about 15 minutes respectively), but once loaded lookups are very
 speedy.
 
-Prerequisite bitarray lib:
-
-mod_pottymouth uses a modified version of the 'etbloom' library that uses 
-'bitarray' to replace 'hipe_bifs'. Ejabberd doesn't handle installing 
-dependences of dependecies quite so well (etbloom being a dep of mod_pottymouth 
-and bitarray being a dep of etbloom), so bitarray needs to be installed manually 
-before installation of mod_pottymouth.
-
-This is how I got it to work... YMMV.
-
-1. Make sure ejabberd is running
-2. Get the updated ejabberd-contrib sources:
-   ejabberdctl modules_update_specs
-3. Execute this script to get and build the dependencies:
-   ~/.ejabberd-modules/sources/ejabberd-contrib/mod_pottymouth/make-deps.sh
-4. When you install the module, its dependencies will be installed as well:
-   ejabberdctl module_install mod_pottymouth
-
 Configuration file is ~/.ejabberd-modules/mod_pottymouth/conf/mod_pottymouth.yml
 
 modules:
@@ -73,8 +55,3 @@ Blacklist helper
 Thinking of a bunch of swear words and all the permutations can be tough. We made
 a helper script to take a bare wordlist and generate permutations given a
 dictionary of substitution characters: https://github.com/madglory/permute_wordlist
-
-Tip of the hat:
-
-This mod makes use of the excellent 'etbloom' module:
-https://github.com/erlangtoolbox/etbloom

mod_pottymouth/make-deps.sh

@@ -1,18 +0,0 @@
-#!/bin/sh
-
-PWD=`pwd`
-
-cd ~/.ejabberd-modules/sources/ejabberd-contrib/mod_pottymouth/
-mkdir deps
-cd deps
-git clone https://github.com/madglory/etbloom.git
-cd etbloom
-rm -rf deps/
-./rebar get-deps
-cp ../../rebar.config.bitarray deps/bitarray/rebar.config
-./rebar compile
-cp -R deps/bitarray/ebin ../../
-cp -R deps/bitarray/priv ../../
-cp -R deps/proper/ebin ../../
-
-cd $PWD

mod_pottymouth/rebar.config.bitarray

@@ -1,14 +0,0 @@
-{ct_extra_params, "-env ERL_LIBS deps/"}.
-{port_env,
-    [ {"DRV_CFLAGS", "-fPIC -O2 $ERL_CFLAGS"},
-      {"ERL_LDFLAGS", " -L$ERL_EI_LIBDIR -lei"}
-    ]}.
-{port_specs, [{"priv/bitarray.so", ["c_src/bitarray_nif.c"]}]}.
-
-
-{deps, [
- %% For runtime
- %% --
- %% For tests
-  {proper, "1.2",
-    {git, "https://github.com/manopapad/proper.git", {tag, "v1.2"}}}]}.

mod_pottymouth/src/banword_gen_server.erl

@@ -0,0 +1,77 @@
+-module(banword_gen_server).
+
+-behaviour(gen_server).
+
+-include("logger.hrl").
+
+-export([member/1]).
+
+%% gen_server callbacks
+-export([start/1, stop/0, init/1, handle_call/3, handle_cast/2, handle_info/2,
+        terminate/2, code_change/3]).
+
+serverName(Lang) ->
+  list_to_atom(lists:flatten([atom_to_list(?MODULE), "_", atom_to_list(Lang)])).
+
+member({Lang, Word} = _MessageToken) ->
+  gen_server:call(serverName(Lang), {member, Word}).
+
+start({Lang, BlacklistFile} = _Opts) ->
+  Name = serverName(Lang),
+  ?INFO_MSG("Building blacklist name ~p~n", [Name]),
+  gen_server:start_link({local, serverName(Lang)}, ?MODULE, [BlacklistFile], []).
+
+stop() ->
+    ok.
+
+readlines(FileName) ->
+    {ok, Data} = file:read_file(FileName),
+    BinList = binary:split(Data, [<<"\n">>], [global]),
+    [binary_to_list(X) || X <- BinList].
+
+init([BlacklistFile]) ->
+  ?INFO_MSG("Building blacklist ~p~n", [BlacklistFile]),
+  {ok, loadWordList(BlacklistFile)}.
+
+check_banword(Word, BlackWord) ->
+  try 
+    % ?INFO_MSG("== CHECK == ~p ~p~n", [Word, BlackWord]),
+    Res = string:rstr(Word, BlackWord),
+    if 
+      Res > 0 ->
+        true;
+      true ->
+        false
+    end
+  catch _ -> 
+    false
+  end.
+
+handle_call({member, Word}, _From, BlackList) ->
+  % ?INFO_MSG("~p ~p~n", [Word, BlackList]),
+  lists:foreach(
+    fun(Elem) -> 
+      Res = check_banword(Word, Elem),
+      if 
+        Res ->
+          throw({reply, true, BlackList});
+        true ->
+          false          
+      end
+    end, BlackList),
+  {reply, false, BlackList}.
+
+handle_cast(_Msg, State) -> {noreply, State}.
+handle_info(_Info, State) -> {noreply, State}.
+terminate(_Reason, _State) -> ok.
+code_change(_OldVsn, State, _Extra) -> {ok, State}.
+
+loadWordList(BlacklistFile) ->
+  BlacklistExists = filelib:is_file(BlacklistFile),
+  if
+    BlacklistExists ->
+      readlines(BlacklistFile);
+    true ->
+      ?ERROR_MSG("Blacklist file not found: ~p~n", [BlacklistFile]),
+      []
+  end.

mod_pottymouth/src/bloom_gen_server.erl

@@ -1,54 +0,0 @@
--module(bloom_gen_server).
-
--behaviour(gen_server).
-
--include("logger.hrl").
-
--import(etbloom, [bloom/1, member/2]).
--export([member/1]).
-
-%% gen_server callbacks
--export([start/1, stop/1, init/1, handle_call/3, handle_cast/2, handle_info/2,
-        terminate/2, code_change/3]).
-
-serverName(Lang) ->
-  list_to_atom(lists:flatten([atom_to_list(?MODULE), "_", atom_to_list(Lang)])).
-
-member({Lang, Word} = _MessageToken) ->
-  gen_server:call(serverName(Lang), {member, Word}).
-
-start({Lang, BlacklistFile} = _Opts) ->
-  gen_server:start_link({local, serverName(Lang)}, ?MODULE, [BlacklistFile], []).
-
-stop({Lang, _BlacklistFile} = _Opts) ->
-    gen_server:stop(serverName(Lang)).
-
-init([BlacklistFile]) ->
-  ?INFO_MSG("Building bloom ~p~n", [BlacklistFile]),
-  Bloom = etbloom:sbf(10000000),
-  {ok, loadWordList(Bloom, BlacklistFile)}.
-
-handle_call({member, Word}, _From, Bloom) ->
-  Reply = etbloom:member(Word, Bloom),
-  {reply, Reply, Bloom}.
-
-handle_cast(_Msg, State) -> {noreply, State}.
-handle_info(_Info, State) -> {noreply, State}.
-terminate(_Reason, _State) -> ok.
-code_change(_OldVsn, State, _Extra) -> {ok, State}.
-
-loadWordList(Bloom, BlacklistFile) ->
-  BlacklistExists = filelib:is_file(BlacklistFile),
-  if
-    BlacklistExists ->
-      {ok, S} = file:open(BlacklistFile, read),
-      loadWordList(io:get_line(S, ''), Bloom, S);
-    true ->
-      ?ERROR_MSG("Blacklist file not found: ~p~n", [BlacklistFile]),
-      loadWordList(eof, Bloom, BlacklistFile)
-  end.
-
-loadWordList(eof, Bloom, _S) ->
-  Bloom;
-loadWordList(Line, Bloom, S) ->
-  loadWordList(io:get_line(S, ''), etbloom:add(lists:droplast(Line), Bloom), S).

mod_pottymouth/src/mod_pottymouth.erl

@@ -15,7 +15,7 @@
   mod_options/1
 ]).
 
--import(bloom_gen_server, [start/0, stop/0, member/1]).
+-import(banword_gen_server, [start/0, stop/0, member/1]).
 -import(nomalize_leet_gen_server, [normalize/1]).
 
 getMessageLang(Msg) ->
@@ -31,8 +31,8 @@ getMessageLang(Msg) ->
 censorWord({Lang, Word} = _MessageTerm) ->
   % we need unicode characters to normlize the word
   NormalizedWord = normalize_leet_gen_server:normalize({Lang, unicode:characters_to_list(list_to_binary(Word))}),
-  % we need bytewise format for bloom lookup
-  IsBadWord = bloom_gen_server:member({Lang, binary_to_list(unicode:characters_to_binary(NormalizedWord))}),
+  % we need bytewise format for banword lookup
+  IsBadWord = banword_gen_server:member({Lang, binary_to_list(unicode:characters_to_binary(NormalizedWord))}),
   if
     IsBadWord ->
       "****";
@@ -61,7 +61,7 @@ filterMessageText2(Lang, MessageText) ->
 
 start(_Host, Opts) ->
   Blacklists = gen_mod:get_opt(blacklists, Opts),
-  lists:map(fun bloom_gen_server:start/1, Blacklists),
+  lists:map(fun banword_gen_server:start/1, Blacklists),
   CharMaps = gen_mod:get_opt(charmaps, Opts),
   lists:map(fun normalize_leet_gen_server:start/1, CharMaps),
   ejabberd_hooks:add(filter_packet, global, ?MODULE, on_filter_packet, 0),
@@ -69,7 +69,7 @@ start(_Host, Opts) ->
 
 stop(Host) ->
   Blacklists = gen_mod:get_module_opt(Host, ?MODULE, blacklists),
-  lists:map(fun bloom_gen_server:stop/1, Blacklists),
+  lists:map(fun banword_gen_server:stop/1, Blacklists),
   CharMaps = gen_mod:get_module_opt(Host, ?MODULE, charmaps),
   lists:map(fun normalize_leet_gen_server:stop/1, CharMaps),
   ejabberd_hooks:delete(filter_packet, global, ?MODULE, on_filter_packet, 0),