feat: auto subscribe, todo: test SUITE

apps/emqx_auto_subscribe/.gitignore

@@ -0,0 +1,19 @@
+.rebar3
+_*
+.eunit
+*.o
+*.beam
+*.plt
+*.swp
+*.swo
+.erlang.cookie
+ebin
+log
+erl_crash.dump
+.rebar
+logs
+_build
+.idea
+*.iml
+rebar3.crashdump
+*~

apps/emqx_auto_subscribe/LICENSE

@@ -0,0 +1,191 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
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+      the terms of any separate license agreement you may have executed
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+   6. Trademarks. This License does not grant permission to use the trade
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+      negligent acts) or agreed to in writing, shall any Contributor be
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+   9. Accepting Warranty or Additional Liability. While redistributing
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+
+   END OF TERMS AND CONDITIONS
+
+   Copyright 2021, DDDHuang <904897578@qq.com>.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
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+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+

apps/emqx_auto_subscribe/README.md

@@ -0,0 +1,9 @@
+emqx_auto_subscribe
+=====
+
+An OTP application
+
+Build
+-----
+
+    $ rebar3 compile

apps/emqx_auto_subscribe/etc/emqx_auto_subscribe.conf

@@ -0,0 +1,29 @@
+
+auto_subscribe {
+    topics = [
+        # {
+        #     topic = "/c/${clientid}",
+        #     qos   = 0
+        # },
+        # {
+        #     topic = "/u/${username}",
+        #     qos   = 1
+        # },
+        # {
+        #     topic = "/h/${host}",
+        #     qos   = 2
+        # },
+        # {
+        #     topic = "/p/${port}",
+        #     qos   = 0
+        # },
+        # {
+        #     topic = "/topic/abc",
+        #     qos   = 0
+        # },
+        # {
+        #     topic = "/client/${clientid}/username/${username}/host/${host}/port/${port}",
+        #     qos   = 0
+        # }
+    ]
+}

apps/emqx_auto_subscribe/rebar.config

@@ -0,0 +1,6 @@
+{erl_opts, [debug_info]}.
+{deps, []}.
+
+{shell, [
+    {apps, [emqx_auto_subscribe]}
+]}.

apps/emqx_auto_subscribe/src/emqx_auto_subscribe.app.src

@@ -0,0 +1,15 @@
+{application, emqx_auto_subscribe,
+ [{description, "An OTP application"},
+  {vsn, "0.1.0"},
+  {registered, []},
+  {mod, {emqx_auto_subscribe_app, []}},
+  {applications,
+   [kernel,
+    stdlib
+   ]},
+  {env,[]},
+  {modules, []},
+
+  {licenses, ["Apache 2.0"]},
+  {links, []}
+ ]}.

apps/emqx_auto_subscribe/src/emqx_auto_subscribe.erl

@@ -0,0 +1,80 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_auto_subscribe).
+
+-define(HOOK_POINT, 'client.connected').
+
+-define(MAX_AUTO_SUBSCRIBE, 20).
+
+-export([load/0]).
+
+-export([ max_limit/0
+        , list/0
+        , update/1
+        , test/1
+        ]).
+
+%% hook callback
+-export([on_client_connected/3]).
+
+load() ->
+    update_hook().
+
+max_limit() ->
+    ?MAX_AUTO_SUBSCRIBE.
+
+list() ->
+    emqx:get_config([auto_subscribe, topics], []).
+
+update(Topics) ->
+    update_(Topics).
+
+test(_) ->
+%% TODO: test rule with info map
+    ok.
+
+% test(Topic) when is_map(Topic) ->
+%     test([Topic]);
+
+% test(Topics) when is_list(Topics) ->
+%     PlaceHolders = emqx_auto_subscribe_placeholder:generate(Topics),
+%     ClientInfo = #{},
+%     ConnInfo = #{},
+%     emqx_auto_subscribe_placeholder:to_topic_table([PlaceHolders], ClientInfo, ConnInfo).
+
+%%--------------------------------------------------------------------
+%% hook
+
+on_client_connected(ClientInfo, ConnInfo, {TopicHandler, Options}) ->
+    TopicTables = erlang:apply(TopicHandler, handle, [ClientInfo, ConnInfo, Options]),
+    self() ! {subscribe, TopicTables};
+on_client_connected(_, _, _) ->
+    ok.
+
+%%--------------------------------------------------------------------
+%% internal
+
+update_(Topics) when length(Topics) =< ?MAX_AUTO_SUBSCRIBE ->
+    {ok, _} = emqx:update_config([auto_subscribe, topics], Topics),
+    update_hook();
+update_(_Topics) ->
+    {error, quota_exceeded}.
+
+update_hook() ->
+    {TopicHandler, Options} = emqx_auto_subscribe_handler:init(),
+    emqx_hooks:put(?HOOK_POINT, {?MODULE, on_client_connected, [{TopicHandler, Options}]}),
+    ok.

apps/emqx_auto_subscribe/src/emqx_auto_subscribe_api.erl

@@ -0,0 +1,64 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_auto_subscribe_api).
+
+-behaviour(minirest_api).
+
+-export([api_spec/0]).
+
+-export([auto_subscribe/2]).
+
+-define(EXCEED_LIMIT, 'EXCEED_LIMIT').
+
+api_spec() ->
+    {[auto_subscribe_api()], []}.
+
+schema() ->
+    emqx_mgmt_util:schema(
+        emqx_mgmt_api_configs:gen_schema(
+            emqx:get_raw_config([auto_subscribe, topics]))).
+
+auto_subscribe_api() ->
+    Metadata = #{
+        get => #{
+            description => <<"Auto subscribe list">>,
+            responses => #{
+                <<"200">> => schema()}},
+        put => #{
+            description => <<"Update auto subscribe topic list">>,
+            'requestBody' => schema(),
+            responses => #{
+                <<"200">> => schema(),
+                <<"409">> => emqx_mgmt_util:error_schema(
+                                <<"Auto Subscribe topics max limit">>, [?EXCEED_LIMIT])}}
+    },
+    {"/mqtt/auto_subscribe", Metadata, auto_subscribe}.
+
+%%%==============================================================================================
+%% api apply
+auto_subscribe(get, _) ->
+    {200, emqx_auto_subscribe:list()};
+
+auto_subscribe(put, #{body := Params}) ->
+    case emqx_auto_subscribe:update(Params) of
+        {error, quota_exceeded} ->
+            Message = list_to_binary(io_lib:format("Max auto subscribe topic count is  ~p",
+                                        [emqx_auto_subscribe:max_limit()])),
+            {409, #{code => ?EXCEED_LIMIT, message => Message}};
+        ok ->
+            {200, emqx_auto_subscribe:list()}
+    end.

apps/emqx_auto_subscribe/src/emqx_auto_subscribe_app.erl

@@ -0,0 +1,30 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_auto_subscribe_app).
+
+-behaviour(application).
+
+-export([start/2, stop/1]).
+
+start(_StartType, _StartArgs) ->
+    ok = emqx_auto_subscribe:load(),
+    emqx_auto_subscribe_sup:start_link().
+
+stop(_State) ->
+    ok.
+
+%% internal functions

apps/emqx_auto_subscribe/src/emqx_auto_subscribe_placeholder.erl

@@ -0,0 +1,72 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+-module(emqx_auto_subscribe_placeholder).
+
+-export([generate/1]).
+
+-export([to_topic_table/3]).
+
+-spec(generate(list() | map()) -> list() | map()).
+generate(Topics) when is_list(Topics) ->
+    [generate(Topic) || Topic <- Topics];
+
+generate(#{qos := Qos, topic := Topic}) when is_binary(Topic) ->
+    #{qos => Qos, placeholder => generate(Topic, [])}.
+
+-spec(to_topic_table(list(), map(), map()) -> list()).
+to_topic_table(PlaceHolders, ClientInfo, ConnInfo) ->
+    [begin
+        Topic0 = to_topic(PlaceHolder, ClientInfo, ConnInfo, []),
+        {Topic, Opts} = emqx_topic:parse(Topic0),
+        {Topic, Opts#{qos => Qos}}
+     end || #{qos := Qos, placeholder := PlaceHolder} <- PlaceHolders].
+
+%%--------------------------------------------------------------------
+%% internal
+
+generate(<<"">>, Result) ->
+    lists:reverse(Result);
+generate(<<"${clientid}", Tail/binary>>, Result) ->
+    generate(Tail, [clientid | Result]);
+generate(<<"${username}", Tail/binary>>, Result) ->
+    generate(Tail, [username | Result]);
+generate(<<"${host}", Tail/binary>>, Result) ->
+    generate(Tail, [host | Result]);
+generate(<<"${port}", Tail/binary>>, Result) ->
+    generate(Tail, [port | Result]);
+generate(<<Char:8, Tail/binary>>, []) ->
+    generate(Tail, [<<Char:8>>]);
+generate(<<Char:8, Tail/binary>>, [R | Result]) when is_binary(R) ->
+    generate(Tail, [<<R/binary, Char:8>> | Result]);
+generate(<<Char:8, Tail/binary>>, [R | Result]) when is_atom(R) ->
+    generate(Tail, [<<Char:8>> | [R | Result]]).
+
+to_topic([], _, _, Res) ->
+    list_to_binary(lists:reverse(Res));
+to_topic([Binary | PTs], C, Co, Res) when is_binary(Binary) ->
+    to_topic(PTs, C, Co, [Binary | Res]);
+to_topic([clientid | PTs], C = #{clientid := ClientID}, Co, Res) ->
+    to_topic(PTs, C, Co, [ClientID | Res]);
+to_topic([username | PTs], C = #{username := undefined}, Co, Res) ->
+    to_topic(PTs, C, Co, [<<"undefined">> | Res]);
+to_topic([username | PTs], C = #{username := Username}, Co, Res) ->
+    to_topic(PTs, C, Co, [Username | Res]);
+to_topic([host | PTs], C, Co = #{peername := {Host, _}}, Res) ->
+    HostBinary = list_to_binary(inet:ntoa(Host)),
+    to_topic(PTs, C, Co, [HostBinary | Res]);
+to_topic([port | PTs], C, Co = #{peername := {_, Port}}, Res) ->
+    PortBinary = integer_to_binary(Port),
+    to_topic(PTs, C, Co, [PortBinary | Res]).

apps/emqx_auto_subscribe/src/emqx_auto_subscribe_schema.erl

@@ -0,0 +1,34 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+-module(emqx_auto_subscribe_schema).
+
+-behaviour(hocon_schema).
+
+-include_lib("typerefl/include/types.hrl").
+
+-export([ structs/0
+        , fields/1]).
+
+structs() ->
+    ["auto_subscribe"].
+
+fields("auto_subscribe") ->
+    [ {topics, hoconsc:array(hoconsc:ref(?MODULE, "topic"))}];
+
+fields("topic") ->
+    [ {topic, emqx_schema:t(binary(), undefined, <<"">>)}
+    , {qos, emqx_schema:t(integer(), undefined, 0)}
+    ].

apps/emqx_auto_subscribe/src/emqx_auto_subscribe_sup.erl

@@ -0,0 +1,37 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_auto_subscribe_sup).
+
+-behaviour(supervisor).
+
+-export([start_link/0]).
+
+-export([init/1]).
+
+-define(SERVER, ?MODULE).
+
+start_link() ->
+    supervisor:start_link({local, ?SERVER}, ?MODULE, []).
+
+init([]) ->
+    SupFlags = #{strategy => one_for_all,
+                 intensity => 0,
+                 period => 1},
+    ChildSpecs = [],
+    {ok, {SupFlags, ChildSpecs}}.
+
+%% internal functions

apps/emqx_auto_subscribe/src/topics_handler/emqx_auto_subscribe_handler.erl

@@ -0,0 +1,29 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+-module(emqx_auto_subscribe_handler).
+
+-export([init/0]).
+
+-spec(init() -> {Module :: atom(), Config :: term()}).
+init() ->
+    do_init(emqx:get_config([auto_subscribe], #{})).
+
+do_init(Config = #{topics := _Topics}) ->
+    Options = emqx_auto_subscribe_internal:init(Config),
+    {emqx_auto_subscribe_internal, Options};
+
+do_init(_) ->
+    erlang:error("only support in EMQ X Enterprise").

apps/emqx_auto_subscribe/src/topics_handler/emqx_auto_subscribe_internal.erl

@@ -0,0 +1,29 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+-module(emqx_auto_subscribe_internal).
+
+-export([init/1]).
+
+-export([handle/3]).
+
+-spec(init(Config :: map()) -> HandlerOptions :: term()).
+init(#{topics := Topics}) ->
+    emqx_auto_subscribe_placeholder:generate(Topics).
+
+-spec(handle(ClientInfo :: map(), ConnInfo :: map(), HandlerOptions :: term()) ->
+    TopicTables :: list()).
+handle(ClientInfo, ConnInfo, PlaceHolders) ->
+    emqx_auto_subscribe_placeholder:to_topic_table(PlaceHolders, ClientInfo, ConnInfo).

apps/emqx_machine/src/emqx_machine_schema.erl

@@ -48,6 +48,7 @@
         , emqx_statsd_schema
         , emqx_authn_schema
         , emqx_authz_schema
+        , emqx_auto_subscribe_schema
         , emqx_bridge_mqtt_schema
         , emqx_modules_schema
         , emqx_management_schema

rebar.config.erl

@@ -267,6 +267,7 @@ relx_apps(ReleaseType) ->
     , emqx_connector
     , emqx_authn
     , emqx_authz
+    , emqx_auto_subscribe
     , emqx_gateway
     , emqx_exhook
     , emqx_data_bridge