fix mqtt connection
This commit is contained in:
parent
41e88100ec
commit
ff1fb5e363
@ -1,197 +1,185 @@
|
||||
%%%-------------------------------------------------------------------
|
||||
%%% @author aresei
|
||||
%%% @doc
|
||||
%%% MQTT Client based on gen_statem
|
||||
%%% MQTT Client based on gen_statem (state_functions)
|
||||
%%% 自动重连 + 掉线期间 publish 入队 + flush 队列
|
||||
%%%-------------------------------------------------------------------
|
||||
-module(iot_mqtt_connection).
|
||||
-author("aresei").
|
||||
-behaviour(gen_statem).
|
||||
|
||||
-include("iot.hrl").
|
||||
|
||||
%% API
|
||||
-export([start_link/2, publish_status/1, publish_msg/2]).
|
||||
|
||||
%% gen_statem callbacks
|
||||
-export([init/1, callback_mode/0, handle_event/4, terminate/3, code_change/4]).
|
||||
|
||||
-define(DISCONNECTED, disconnected).
|
||||
-define(CONNECTED, connected).
|
||||
-export([init/1, callback_mode/0, disconnected/3, connected/3, terminate/3, code_change/4]).
|
||||
|
||||
-record(state, {
|
||||
parent_pid :: pid(),
|
||||
conn_pid = undefined :: pid() | undefined,
|
||||
retry = 0 :: non_neg_integer(),
|
||||
topics = [] :: list(),
|
||||
%% 掉线期间 publish 缓冲
|
||||
queue = queue:new() :: queue:queue()
|
||||
parent_pid :: pid(),
|
||||
conn_pid :: pid() | undefined,
|
||||
retry :: non_neg_integer(),
|
||||
topics :: list(),
|
||||
queue :: queue:queue()
|
||||
}).
|
||||
|
||||
%%%===================================================================
|
||||
%%% API
|
||||
%%%===================================================================
|
||||
|
||||
%% 需要订阅的主题信息
|
||||
%% Topics: [{<<"CET/NX/upload">>, 2}]
|
||||
-spec start_link(ParentPid :: pid(), Topics :: list()) -> {ok, pid()} | ignore | {error, term()}.
|
||||
start_link(ParentPid, Topics) when is_pid(ParentPid), is_list(Topics) ->
|
||||
-spec start_link(pid(), list()) ->
|
||||
{ok, pid()} | ignore | {error, term()}.
|
||||
start_link(ParentPid, Topics)
|
||||
when is_pid(ParentPid), is_list(Topics) ->
|
||||
gen_statem:start_link(?MODULE, [ParentPid, Topics], []).
|
||||
|
||||
-spec publish_status(ConnPid :: pid()) -> #{state := atom(), retry := non_neg_integer(), queue_len := non_neg_integer()}.
|
||||
publish_status(ConnPid) when is_pid(ConnPid) ->
|
||||
gen_statem:call(ConnPid, status).
|
||||
-spec publish_status(pid()) -> map().
|
||||
publish_status(Pid) when is_pid(Pid) ->
|
||||
gen_statem:call(Pid, status).
|
||||
|
||||
-spec publish_msg(ConnPid :: pid(), Msg :: any()) -> ok.
|
||||
publish_msg(ConnPid, Msg) when is_pid(ConnPid) ->
|
||||
gen_statem:cast(ConnPid, {publish, Msg}).
|
||||
-spec publish_msg(pid(), any()) -> ok.
|
||||
publish_msg(Pid, Msg) when is_pid(Pid) ->
|
||||
gen_statem:cast(Pid, {publish, Msg}).
|
||||
|
||||
%%%===================================================================
|
||||
%%% gen_statem callbacks
|
||||
%%%===================================================================
|
||||
|
||||
callback_mode() ->
|
||||
handle_event_function.
|
||||
state_functions.
|
||||
|
||||
-spec init([]) -> {ok, StateName :: atom(), StateData :: #state{}}.
|
||||
init([ParentPid, Topics]) ->
|
||||
%% 尝试建立到服务器的连接
|
||||
self() ! start_connect,
|
||||
{ok, ?DISCONNECTED, #state{parent_pid = ParentPid, topics = Topics}}.
|
||||
{ok, disconnected, #state{parent_pid = ParentPid, topics = Topics, retry = 0, conn_pid = undefined, queue = queue:new()}}.
|
||||
|
||||
%%%===================================================================
|
||||
%%% handle_event/4
|
||||
%%% disconnected state
|
||||
%%%===================================================================
|
||||
handle_event(info, start_connect, ?DISCONNECTED, State = #state{retry = Retry, topics = Topics}) ->
|
||||
|
||||
disconnected(info, start_connect, State = #state{retry = Retry, topics = Topics}) ->
|
||||
Opts = iot_config:emqt_opts(<<"host-subscriber">>),
|
||||
lager:debug("[mqtt] connecting, opts: ~p", [Opts]),
|
||||
lager:debug("[mqtt] connecting, opts=~p", [Opts]),
|
||||
case emqtt:start_link(Opts) of
|
||||
{ok, ConnPid} ->
|
||||
{ok, _} = emqtt:connect(ConnPid),
|
||||
case length(Topics) > 0 of
|
||||
true ->
|
||||
SubscribeResult = emqtt:subscribe(ConnPid, Topics),
|
||||
lager:debug("[mqtt] connected pid: ~p subscribed: ~p", [ConnPid, SubscribeResult]);
|
||||
false ->
|
||||
ok
|
||||
end,
|
||||
maybe_subscribe(ConnPid, Topics),
|
||||
NState = flush_queue(ConnPid, State#state{conn_pid = ConnPid, retry = 0}),
|
||||
{next_state, ?CONNECTED, NState};
|
||||
ignore ->
|
||||
lager:debug("[mqtt] start_link returned ignore"),
|
||||
try_reconnect(),
|
||||
{next_state, ?DISCONNECTED, State#state{retry = Retry + 1}};
|
||||
{error, Reason} ->
|
||||
lager:debug("[mqtt] start_link returned error: ~p", [Reason]),
|
||||
try_reconnect(),
|
||||
{next_state, ?DISCONNECTED, State#state{retry = Retry + 1}}
|
||||
{next_state, connected, NState};
|
||||
_ ->
|
||||
{keep_state, State#state{retry = Retry + 1}, [{timeout, start_connect, 5000}]}
|
||||
end;
|
||||
|
||||
%% -------------------------------
|
||||
%% connected 状态
|
||||
%% -------------------------------
|
||||
handle_event(cast, {publish, Msg}, ?CONNECTED, State = #state{conn_pid = ConnPid}) ->
|
||||
do_publish(ConnPid, Msg),
|
||||
{keep_state, State};
|
||||
%% 掉线期间 publish → 入队
|
||||
disconnected(cast, {publish, Msg}, State = #state{queue = Q}) ->
|
||||
{keep_state, State#state{queue = enqueue(Q, Msg)}};
|
||||
|
||||
handle_event(info, {disconnect, ReasonCode, _Props}, ?CONNECTED, State = #state{conn_pid = _ConnPid}) ->
|
||||
lager:debug("[mqtt] disconnected ReasonCode: ~p", [ReasonCode]),
|
||||
try_reconnect(),
|
||||
{next_state, ?DISCONNECTED, State#state{conn_pid = undefined}};
|
||||
%% status
|
||||
disconnected({call, From}, status, State) ->
|
||||
reply_status(disconnected, From, State);
|
||||
|
||||
%% -------------------------------
|
||||
%% disconnected / reconnect_wait 状态收到 publish
|
||||
%% -------------------------------
|
||||
handle_event(cast, {publish, Msg}, ?DISCONNECTED, State = #state{queue = Queue}) ->
|
||||
NewQueue = enqueue(Queue, Msg),
|
||||
{keep_state, State#state{queue = NewQueue}};
|
||||
|
||||
%% -------------------------------
|
||||
%% call
|
||||
%% -------------------------------
|
||||
handle_event({call, From}, status, StateName, State = #state{retry = Retry}) ->
|
||||
Reply = #{
|
||||
state => StateName,
|
||||
retry => Retry,
|
||||
queue_len => queue:len(State#state.queue)
|
||||
},
|
||||
{keep_state, State, [{reply, From, Reply}]};
|
||||
|
||||
%% -------------------------------
|
||||
%% 收到推送消息
|
||||
%% -------------------------------
|
||||
handle_event(info, {publish, #{packet_id := _PacketId, payload := Payload, qos := Qos, topic := Topic}}, _StateName, State = #state{parent_pid = ParentPid}) ->
|
||||
lager:debug("[iot_mqtt_subscriber] Recv a topic: ~p, publish packet: ~p, qos: ~p", [Topic, Payload, Qos]),
|
||||
%% 将消息分发到对应的host进程去处理
|
||||
ParentPid ! {mqtt_message, Topic, Payload, Qos},
|
||||
{keep_state, State};
|
||||
handle_event(info, {puback, Packet = #{packet_id := _PacketId}}, _, State = #state{}) ->
|
||||
lager:debug("[iot_mqtt_subscriber] receive puback packet: ~p", [Packet]),
|
||||
{keep_state, State};
|
||||
|
||||
%% -------------------------------
|
||||
%% 默认信息处理
|
||||
%% -------------------------------
|
||||
handle_event(_Type, Info, StateName, State) ->
|
||||
lager:debug("[mqtt] unhandled event ~p in state ~p", [Info, StateName]),
|
||||
%% 兜底
|
||||
disconnected(_Type, _Event, State) ->
|
||||
{keep_state, State}.
|
||||
|
||||
%%%===================================================================
|
||||
%%% Internal functions
|
||||
%%% connected state
|
||||
%%%===================================================================
|
||||
|
||||
-spec enqueue(Queue :: queue:queue(), Msg :: any()) -> NQueue :: queue:queue().
|
||||
enqueue(Queue, Msg) ->
|
||||
%% 队列最大长度 1000
|
||||
case queue:len(Queue) < 1000 of
|
||||
%% 正常 publish
|
||||
connected(cast, {publish, Msg}, State = #state{conn_pid = ConnPid}) ->
|
||||
do_publish(ConnPid, Msg),
|
||||
{keep_state, State};
|
||||
|
||||
%% MQTT 断线
|
||||
connected(info, {disconnect, ReasonCode, _Props}, State) ->
|
||||
lager:warning("[mqtt] disconnected, reason=~p", [ReasonCode]),
|
||||
{next_state, disconnected, State#state{conn_pid = undefined}, [{timeout, start_connect, 5000}]};
|
||||
|
||||
%% 收到订阅消息
|
||||
connected(info, {publish, #{topic := Topic, payload := Payload, qos := Qos}}, State = #state{parent_pid = ParentPid}) ->
|
||||
ParentPid ! {mqtt_message, Topic, Payload, Qos},
|
||||
{keep_state, State};
|
||||
|
||||
%% puback
|
||||
connected(info, {puback, Packet}, _State) ->
|
||||
lager:debug("[mqtt] puback ~p", [Packet]),
|
||||
keep_state_and_data;
|
||||
|
||||
%% status
|
||||
connected({call, From}, status, State) ->
|
||||
reply_status(connected, From, State);
|
||||
|
||||
%% 兜底
|
||||
connected(_Type, _Event, State) ->
|
||||
{keep_state, State}.
|
||||
|
||||
%%%===================================================================
|
||||
%%% Internal helpers
|
||||
%%%===================================================================
|
||||
|
||||
-spec enqueue(queue:queue(), any()) -> queue:queue().
|
||||
enqueue(Q, Msg) ->
|
||||
case queue:len(Q) < 1000 of
|
||||
true ->
|
||||
queue:in(Msg, Queue);
|
||||
queue:in(Msg, Q);
|
||||
false ->
|
||||
lager:warning("[mqtt] queue full, dropping message ~p", [Msg]),
|
||||
Queue
|
||||
lager:warning("[mqtt] queue full, drop msg"),
|
||||
Q
|
||||
end.
|
||||
|
||||
-spec flush_queue(ConnPid :: pid(), State :: #state{}) -> NState :: #state{}.
|
||||
flush_queue(ConnPid, State = #state{queue = Queue}) ->
|
||||
lists:foreach(fun(Msg) -> do_publish(ConnPid, Msg) end, queue:to_list(Queue)),
|
||||
-spec flush_queue(pid(), #state{}) -> #state{}.
|
||||
flush_queue(ConnPid, State = #state{queue = Q}) ->
|
||||
lists:foreach(
|
||||
fun(Msg) -> do_publish(ConnPid, Msg) end,
|
||||
queue:to_list(Q)
|
||||
),
|
||||
State#state{queue = queue:new()}.
|
||||
|
||||
-spec do_publish(ConnPid :: pid(), Msg :: any()) -> no_return().
|
||||
-spec do_publish(pid(), any()) -> ok.
|
||||
do_publish(ConnPid, Msg) ->
|
||||
try
|
||||
emqtt:publish(ConnPid, Msg)
|
||||
emqtt:publish(ConnPid, Msg),
|
||||
ok
|
||||
catch
|
||||
_:Err ->
|
||||
lager:error("[mqtt] publish failed ~p, requeueing", [Err]),
|
||||
Pid = self(),
|
||||
gen_statem:cast(Pid, {publish, Msg})
|
||||
lager:error("[mqtt] publish failed ~p, requeue", [Err]),
|
||||
gen_statem:cast(self(), {publish, Msg}),
|
||||
ok
|
||||
end.
|
||||
|
||||
%%%===================================================================
|
||||
%%% terminate/3
|
||||
%%%===================================================================
|
||||
-spec terminate(Reason :: term(), StateName :: atom(), State :: #state{}) -> ok.
|
||||
terminate(_Reason, _StateName, #state{conn_pid = undefined}) ->
|
||||
maybe_subscribe(_ConnPid, []) ->
|
||||
ok;
|
||||
terminate(_Reason, _StateName, #state{conn_pid = ConnPid, topics = Topics}) ->
|
||||
case length(Topics) > 0 of
|
||||
true ->
|
||||
TopicNames = lists:map(fun({Name,_}) -> Name end, Topics),
|
||||
{ok, _Props, _ReasonCode} = emqtt:unsubscribe(ConnPid, #{}, TopicNames);
|
||||
false ->
|
||||
ok
|
||||
end,
|
||||
ok = emqtt:disconnect(ConnPid),
|
||||
lager:debug("[mqtt] terminate cleanup done"),
|
||||
maybe_subscribe(ConnPid, Topics) ->
|
||||
SubResult = emqtt:subscribe(ConnPid, Topics),
|
||||
lager:debug("[iot_mqtt_connection] subscribe topics: ~p, result: ~p", [Topics, SubResult]).
|
||||
|
||||
reply_status(StateName, From,
|
||||
#state{retry = Retry, queue = Q} = State) ->
|
||||
Reply = #{
|
||||
state => StateName,
|
||||
retry => Retry,
|
||||
queue_len => queue:len(Q)
|
||||
},
|
||||
{keep_state, State, [{reply, From, Reply}]}.
|
||||
|
||||
%%%===================================================================
|
||||
%%% terminate / code_change
|
||||
%%%===================================================================
|
||||
|
||||
terminate(_Reason, _StateName,
|
||||
#state{conn_pid = undefined}) ->
|
||||
ok;
|
||||
terminate(_Reason, _StateName,
|
||||
#state{conn_pid = ConnPid, topics = Topics}) ->
|
||||
maybe_unsubscribe(ConnPid, Topics),
|
||||
emqtt:disconnect(ConnPid),
|
||||
ok.
|
||||
|
||||
maybe_unsubscribe(_ConnPid, []) ->
|
||||
ok;
|
||||
maybe_unsubscribe(ConnPid, Topics) ->
|
||||
TopicNames = [T || {T, _} <- Topics],
|
||||
emqtt:unsubscribe(ConnPid, #{}, TopicNames),
|
||||
ok.
|
||||
|
||||
%%%===================================================================
|
||||
%%% code_change/4
|
||||
%%%===================================================================
|
||||
-spec code_change(term(), StateName :: atom(), State :: #state{}, Extra :: term()) ->
|
||||
{ok, State :: #state{}}.
|
||||
code_change(_OldVsn, _StateName, State, _Extra) ->
|
||||
{ok, State}.
|
||||
|
||||
try_reconnect() ->
|
||||
erlang:send_after(5000, self(), start_connect).
|
||||
Loading…
x
Reference in New Issue
Block a user