emqx/apps/emqx_gateway_mqttsn/src/emqx_gateway_mqttsn.erl

128 lines
3.6 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 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.
%%--------------------------------------------------------------------
%% @doc The MQTT-SN Gateway implement interface
-module(emqx_gateway_mqttsn).
-include_lib("emqx/include/logger.hrl").
%% define a gateway named stomp
-gateway(#{
name => mqttsn,
callback_module => ?MODULE,
config_schema_module => emqx_mqttsn_schema
}).
%% callback_module must implement the emqx_gateway_impl behaviour
-behaviour(emqx_gateway_impl).
%% callback for emqx_gateway_impl
-export([
on_gateway_load/2,
on_gateway_update/3,
on_gateway_unload/2
]).
-import(
emqx_gateway_utils,
[
normalize_config/1,
start_listeners/4,
stop_listeners/2
]
).
%%--------------------------------------------------------------------
%% emqx_gateway_impl callbacks
%%--------------------------------------------------------------------
on_gateway_load(
_Gateway = #{
name := GwName,
config := Config
},
Ctx
) ->
%% We Also need to start `emqx_mqttsn_broadcast`
case maps:get(broadcast, Config, false) of
false ->
ok;
true ->
%% FIXME:
Port = 1884,
SnGwId = maps:get(gateway_id, Config, undefined),
_ = emqx_mqttsn_broadcast:start_link(SnGwId, Port),
ok
end,
PredefTopics = maps:get(predefined, Config, []),
ok = emqx_mqttsn_registry:persist_predefined_topics(PredefTopics),
NConfig = maps:without([broadcast, predefined], Config),
Listeners = emqx_gateway_utils:normalize_config(NConfig),
ModCfg = #{
frame_mod => emqx_mqttsn_frame,
chann_mod => emqx_mqttsn_channel
},
case
start_listeners(
Listeners, GwName, Ctx, ModCfg
)
of
{ok, ListenerPids} ->
{ok, ListenerPids, _GwState = #{ctx => Ctx}};
{error, {Reason, Listener}} ->
throw(
{badconf, #{
key => listeners,
value => Listener,
reason => Reason
}}
)
end.
on_gateway_update(Config, Gateway, GwState = #{ctx := Ctx}) ->
GwName = maps:get(name, Gateway),
try
%% XXX: 1. How hot-upgrade the changes ???
%% XXX: 2. Check the New confs first before destroy old instance ???
on_gateway_unload(Gateway, GwState),
on_gateway_load(Gateway#{config => Config}, Ctx)
catch
Class:Reason:Stk ->
logger:error(
"Failed to update ~ts; "
"reason: {~0p, ~0p} stacktrace: ~0p",
[GwName, Class, Reason, Stk]
),
{error, Reason}
end.
on_gateway_unload(
_Gateway = #{
name := GwName,
config := Config
},
_GwState
) ->
PredefTopics = maps:get(predefined, Config, []),
ok = emqx_mqttsn_registry:clear_predefined_topics(PredefTopics),
Listeners = normalize_config(Config),
stop_listeners(GwName, Listeners).