增加基于udp的心跳检查机制

apps/iot/include/iot.hrl

@@ -15,6 +15,7 @@
 %% 设备是否在线状态
 -define(DEVICE_OFFLINE, 0).
 -define(DEVICE_ONLINE, 1).
+-define(DEVICE_UNKNOWN, 2).
 
 %% 下发的任务状态
 -define(TASK_STATUS_INIT,   -1).  %% 未接入

apps/iot/src/http_handler/host_handler.erl

@@ -32,6 +32,16 @@ handle_request("GET", "/host/metric", #{<<"uuid">> := UUID}, _) ->
             end
     end;
 
+%% 处理主机的授权的 取消激活
+handle_request("GET", "/host/status", _, #{<<"uuid">> := UUID}) when is_binary(UUID) ->
+    case iot_host:get_pid(UUID) of
+        undefined ->
+            {ok, 200, iot_util:json_error(404, <<"host not found">>)};
+        Pid when is_pid(Pid) ->
+            {ok, StatusInfo} = iot_host:get_status(Pid),
+            {ok, 200, iot_util:json_data(StatusInfo)}
+    end;
+
 %% 重新加载对应的主机信息
 handle_request("POST", "/host/reload", _, #{<<"uuid">> := UUID}) when is_binary(UUID) ->
     lager:debug("[host_handler] will reload host uuid: ~p", [UUID]),

apps/iot/src/iot_app.erl

@@ -19,6 +19,8 @@ start(_StartType, _StartArgs) ->
 
     %% 加速内存的回收
     erlang:system_flag(fullsweep_after, 16),
+    %% 启动udp服务
+    start_udp_server(),
     %% 启动http服务
     start_http_server(),
     %% 启动redis服务器
@@ -84,7 +86,14 @@ start_redis_server() ->
     ],
     {ok, _} = esockd:open(redis_server, Port, TransOpts, {redis_protocol, start_link, []}),
 
-    lager:debug("[iot_app] the rpc server start at: ~p", [Port]).
+    lager:debug("[iot_app] the redis server start at: ~p", [Port]).
+
+start_udp_server() ->
+    {ok, Props} = application:get_env(iot, udp_server),
+    Port = proplists:get_value(port, Props),
+    UdpOpts = [{udp_options, [binary, {reuseaddr, true}]}],
+    {ok, _} = esockd:open_udp(iot_udp_server, Port, UdpOpts, {iot_udp_server, start_link, []}),
+    lager:debug("[iot_app] the udp server start at: ~p", [Port]).
 
 %% 启动内存数据库
 start_mnesia() ->

apps/iot/src/iot_device.erl

@@ -16,7 +16,7 @@
 -export([start_link/2, is_activated/1, change_status/2, reload/1, auth/2]).
 
 %% gen_statem callbacks
--export([init/1, format_status/2, handle_event/4, terminate/3, code_change/4, callback_mode/0]).
+-export([init/1, handle_event/4, terminate/3, code_change/4, callback_mode/0]).
 
 %% 终端是否授权
 -define(DEVICE_AUTH_DENIED, 0).
@@ -43,7 +43,9 @@ get_pid(DeviceUUID) when is_binary(DeviceUUID) ->
 get_name(DeviceUUID) when is_binary(DeviceUUID) ->
     binary_to_atom(<<"iot_device:", DeviceUUID/binary>>).
 
--spec is_activated(Pid :: pid()) -> boolean().
+-spec is_activated(Pid :: pid() | undefined) -> boolean().
+is_activated(undefined) ->
+    false;
 is_activated(Pid) when is_pid(Pid) ->
     gen_statem:call(Pid, is_activated).
 
@@ -103,14 +105,6 @@ init0(#{<<"device_uuid">> := DeviceUUID, <<"status">> := Status, <<"authorize_st
 callback_mode() ->
     handle_event_function.
 
-%% @private
-%% @doc Called (1) whenever sys:get_status/1,2 is called by gen_statem or
-%% (2) when gen_statem terminates abnormally.
-%% This callback is optional.
-format_status(_Opt, [_PDict, _StateName, _State]) ->
-    Status = some_term,
-    Status.
-
 %% @private
 %% @doc If callback_mode is handle_event_function, then whenever a
 %% gen_statem receives an event from call/2, cast/2, or as a normal

apps/iot/src/iot_host.erl

@@ -16,14 +16,18 @@
 -define(STATE_DENIED, denied).
 -define(STATE_SESSION, session).
 
+%% 心跳包检测时间间隔, 2分钟检测一次
+-define(HEARTBEAT_INTERVAL, 120 * 1000).
+
 %% API
 -export([start_link/2, get_name/1, get_alias_name/1, get_pid/1, handle/2, activate/2]).
--export([get_metric/1, publish_message/4, get_aes/1]).
+-export([get_metric/1, publish_message/4, get_aes/1, get_status/1]).
 -export([create_session/2, attach_channel/2]).
 -export([reload_device/2, delete_device/2, activate_device/3]).
+-export([heartbeat/1]).
 
 %% gen_statem callbacks
--export([init/1, format_status/2, handle_event/4, terminate/3, code_change/4, callback_mode/0]).
+-export([init/1, handle_event/4, terminate/3, code_change/4, callback_mode/0]).
 
 -record(state, {
     host_id :: integer(),
@@ -32,6 +36,9 @@
     %% aes的key, 后续通讯需要基于这个加密
     aes = <<>> :: binary(),
 
+    %% 心跳计数器
+    heartbeat_counter = 0 :: integer(),
+
     %% websocket相关
     channel_pid :: undefined | pid(),
     monitor_ref :: undefined | reference(),
@@ -67,6 +74,10 @@ handle(Pid, Packet) when is_pid(Pid) ->
 get_aes(Pid) when is_pid(Pid) ->
     gen_statem:call(Pid, get_aes).
 
+-spec get_status(Pid :: pid()) -> {ok, Status :: map()}.
+get_status(Pid) when is_pid(Pid) ->
+    gen_statem:call(Pid, get_status).
+
 %% 激活主机, true 表示激活； false表示关闭激活
 -spec activate(Pid :: pid(), Auth :: boolean()) -> ok.
 activate(Pid, Auth) when is_pid(Pid), is_boolean(Auth) ->
@@ -116,6 +127,12 @@ delete_device(Pid, DeviceUUID) when is_pid(Pid), is_binary(DeviceUUID) ->
 activate_device(Pid, DeviceUUID, Auth) when is_pid(Pid), is_binary(DeviceUUID), is_boolean(Auth) ->
     gen_statem:call(Pid, {activate_device, DeviceUUID, Auth}).
 
+-spec heartbeat(Pid :: pid()) -> no_return().
+heartbeat(undefined) ->
+    ok;
+heartbeat(Pid) when is_pid(Pid) ->
+    gen_statem:cast(Pid, heartbeat).
+
 %% @doc Creates a gen_statem process which calls Module:init/1 to
 %% initialize. To ensure a synchronized start-up procedure, this
 %% function does not return until Module:init/1 has returned.
@@ -131,17 +148,21 @@ start_link(Name, UUID) when is_atom(Name), is_binary(UUID) ->
 %% gen_statem:start_link/[3,4], this function is called by the new
 %% process to initialize.
 init([UUID]) ->
-    %% 重启时，认为主机是离线状态; 等待主机主动建立连接
     {ok, _} = host_bo:change_status(UUID, ?HOST_OFFLINE),
-
     case host_bo:get_host_by_uuid(UUID) of
         {ok, #{<<"id">> := HostId}} ->
             %% 通过host_id注册别名, 可以避免通过查询数据库获取HostPid
             AliasName = get_alias_name(HostId),
             global:register_name(AliasName, self()),
-
             Aes = list_to_binary(iot_util:rand_bytes(32)),
 
+            %% 启动主机相关的devices
+            {ok, Devices} = device_bo:get_host_devices(HostId),
+            lists:foreach(fun iot_device_sup:ensured_device_started/1, Devices),
+
+            %% 心跳检测机制
+            erlang:start_timer(?HEARTBEAT_INTERVAL, self(), heartbeat_ticker),
+
             {ok, ?STATE_DENIED, #state{host_id = HostId, uuid = UUID, aes = Aes}};
         undefined ->
             lager:warning("[iot_host] host uuid: ~p, loaded from mysql failed", [UUID]),
@@ -154,14 +175,6 @@ init([UUID]) ->
 callback_mode() ->
     handle_event_function.
 
-%% @private
-%% @doc Called (1) whenever sys:get_status/1,2 is called by gen_statem or
-%% (2) when gen_statem terminates abnormally.
-%% This callback is optional.
-format_status(_Opt, [_PDict, _StateName, _State]) ->
-    Status = some_term,
-    Status.
-
 %% @private
 %% @doc If callback_mode is handle_event_function, then whenever a
 %% gen_statem receives an event from call/2, cast/2, or as a normal
@@ -172,6 +185,31 @@ handle_event({call, From}, get_metric, _, State = #state{metrics = Metrics}) ->
 handle_event({call, From}, get_aes, _, State = #state{aes = Aes}) ->
     {keep_state, State, [{reply, From, {ok, Aes}}]};
 
+%% 获取主机的状态
+handle_event({call, From}, get_status, StateName, State = #state{host_id = HostId, channel_pid = ChannelPid, heartbeat_counter = HeartbeatCounter, metrics = Metrics}) ->
+    %% 启动主机相关的devices
+    {ok, Devices} = device_bo:get_host_devices(HostId),
+    DeviceInfos = lists:map(fun(DeviceUUID) ->
+        DevicePid = iot_device:get_pid(DeviceUUID),
+        case iot_device:is_activated(DevicePid) of
+            true ->
+                {DeviceUUID, <<"online">>};
+            false ->
+                {DeviceUUID, <<"offline">>}
+        end
+                            end, Devices),
+
+    Status = if StateName == ?STATE_SESSION -> <<"session">>; true -> <<"denied">> end,
+    HasChannel = (ChannelPid /= undefined),
+    Reply = #{
+        <<"status">> => Status,
+        <<"has_channel">> => HasChannel,
+        <<"heartbeat_counter">> => HeartbeatCounter,
+        <<"metrics">> => Metrics,
+        <<"device_infos">> => DeviceInfos
+    },
+    {keep_state, State, [{reply, From, {ok, Reply}}]};
+
 %% 发送普通格式的消息, 激活的时候，会话时创建不成功的; 发送aes类型的命令的时候，必须要求session是存在的
 handle_event({call, From}, {publish_message, ReceiverPid, CommandType, {aes, Command0}}, ?STATE_SESSION, State = #state{uuid = UUID, aes = AES, channel_pid = ChannelPid}) ->
     lager:debug("[iot_host] host: ~p, will publish aes message: ~p", [UUID, Command0]),
@@ -193,22 +231,20 @@ handle_event({call, From}, {publish_message, _, _, _}, _, State) ->
     {keep_state, State, [{reply, From, {error, <<"主机状态错误，发送命令失败"/utf8>>}}]};
 
 %% 关闭授权
-handle_event({call, From}, {activate, Auth}, StateName, State = #state{host_id = HostId, uuid = UUID, monitor_ref = MRef, channel_pid = ChannelPid}) ->
-    case {StateName, Auth} of
-        {?STATE_DENIED, _} ->
-            {keep_state, State, [{reply, From, ok}]};
-        {?STATE_SESSION, false} ->
-            %% 取消之前的monitor
-            erlang:demonitor(MRef),
-            ws_channel:stop(ChannelPid, closed),
+handle_event({call, From}, {activate, _}, ?STATE_DENIED, State) ->
+    {keep_state, State, [{reply, From, ok}]};
 
-            {ok, _} = host_bo:change_status(UUID, ?HOST_OFFLINE),
-            change_devices_status(HostId, ?DEVICE_OFFLINE),
+handle_event({call, From}, {activate, true}, ?STATE_SESSION, State) ->
+    {keep_state, State, [{reply, From, ok}]};
+handle_event({call, From}, {activate, false}, ?STATE_SESSION, State = #state{host_id = HostId, uuid = UUID, monitor_ref = MRef, channel_pid = ChannelPid}) ->
+    %% 取消之前的monitor
+    erlang:demonitor(MRef),
+    ws_channel:stop(ChannelPid, closed),
 
-            {next_state, ?STATE_DENIED, State#state{monitor_ref = undefined, channel_pid = undefined}, [{reply, From, ok}]};
-        {?STATE_SESSION, true} ->
-            {keep_state, State, [{reply, From, ok}]}
-    end;
+    {ok, _} = host_bo:change_status(UUID, ?HOST_OFFLINE),
+    change_devices_status(HostId, ?DEVICE_UNKNOWN),
+
+    {next_state, ?STATE_DENIED, State#state{monitor_ref = undefined, channel_pid = undefined}, [{reply, From, ok}]};
 
 %% 绑定channel
 handle_event({call, From}, {attach_channel, ChannelPid}, _, State = #state{uuid = UUID, channel_pid = undefined}) ->
@@ -226,7 +262,7 @@ handle_event({call, From}, {attach_channel, ChannelPid}, _, State = #state{uuid
     {keep_state, State#state{channel_pid = ChannelPid, monitor_ref = MRef}, [{reply, From, ok}]};
 
 %% 授权通过后，才能将主机的状态设置为在线状态
-handle_event({call, From}, {create_session, PubKey}, _, State = #state{uuid = UUID, aes = Aes, host_id = HostId}) ->
+handle_event({call, From}, {create_session, PubKey}, _, State = #state{uuid = UUID, aes = Aes}) ->
     {ok, #{<<"authorize_status">> := AuthorizeStatus}} = host_bo:get_host_by_uuid(UUID),
     case AuthorizeStatus =:= 1 of
         true ->
@@ -235,9 +271,6 @@ handle_event({call, From}, {create_session, PubKey}, _, State = #state{uuid = UU
             {ok, AffectedRow} = host_bo:change_status(UUID, ?HOST_ONLINE),
             lager:debug("[iot_host] host_id(~p) uuid: ~p, create_session, will change status, affected_row: ~p", [?STATE_SESSION, UUID, AffectedRow]),
 
-            %% 启动主机相关的device
-            start_devices(HostId),
-
             {next_state, ?STATE_SESSION, State, [{reply, From, {ok, <<10:8, EncReply/binary>>}}]};
         false ->
             lager:debug("[iot_host] host_id(denied) uuid: ~p, create_session, will not change host status", [UUID]),
@@ -378,19 +411,27 @@ handle_event(cast, {handle, {event, Event0}}, ?STATE_SESSION, State = #state{uui
     end,
     {keep_state, State};
 
-%% 当websocket断开的时候，则设置主机状态为下线状态; 主机的状态需要转换
-handle_event(info, {'DOWN', Ref, process, ChannelPid, Reason}, StateName, State = #state{host_id = HostId, uuid = UUID, monitor_ref = Ref, channel_pid = ChannelPid}) ->
-    lager:warning("[iot_host] channel: ~p, down with reason: ~p, state name: ~p, state: ~p", [ChannelPid, Reason, StateName, State]),
-    {ok, _} = host_bo:change_status(UUID, ?HOST_OFFLINE),
-    change_devices_status(HostId, ?DEVICE_OFFLINE),
+%% 心跳机制
+handle_event(cast, heartbeat, _, State = #state{uuid = UUID, heartbeat_counter = HeartbeatCounter}) ->
+    lager:debug("[iot_host] uuip: ~p, get heartbeat, counter is: ~p", [UUID, HeartbeatCounter]),
+    {keep_state, State#state{heartbeat_counter = HeartbeatCounter + 1}};
 
-    %% 会话状态如果链接丢失，需要切换到activated状态，其他情况保持不变
-    case StateName =:= session of
+handle_event(info, {timeout, _, heartbeat_ticker}, StateName, State = #state{uuid = UUID, host_id = HostId, heartbeat_counter = HeartbeatCounter}) ->
+    case StateName =:= ?STATE_DENIED andalso HeartbeatCounter =:= 0 of
         true ->
-            {next_state, activated, State#state{channel_pid = undefined}};
+            {ok, _} = host_bo:change_status(UUID, ?HOST_OFFLINE),
+            change_devices_status(HostId, ?DEVICE_UNKNOWN);
         false ->
-            {keep_state, State#state{channel_pid = undefined}}
-    end;
+            ok
+    end,
+    erlang:start_timer(?HEARTBEAT_INTERVAL, self(), heartbeat_ticker),
+
+    {keep_state, State#state{heartbeat_counter = 0}};
+
+%% 当websocket断开的时候，则设置主机状态为下线状态; 主机的状态需要转换
+handle_event(info, {'DOWN', Ref, process, ChannelPid, Reason}, StateName, State = #state{uuid = UUID, monitor_ref = Ref, channel_pid = ChannelPid}) ->
+    lager:warning("[iot_host] uuid: ~p, channel: ~p, down with reason: ~p, state name: ~p, state: ~p", [UUID, ChannelPid, Reason, StateName, State]),
+    {next_state, ?STATE_DENIED, State#state{channel_pid = undefined}};
 
 handle_event(EventType, EventContent, StateName, State) ->
     lager:warning("[iot_host] unknown event_type: ~p, event: ~p, state name: ~p, state: ~p", [EventType, EventContent, StateName, State]),
@@ -405,7 +446,7 @@ handle_event(EventType, EventContent, StateName, State) ->
 terminate(Reason, StateName, _State = #state{host_id = HostId, uuid = UUID}) ->
     lager:debug("[iot_host] host: ~p, terminate with reason: ~p, state_name: ~p", [UUID, Reason, StateName]),
     host_bo:change_status(UUID, ?HOST_OFFLINE),
-    change_devices_status(HostId, ?DEVICE_OFFLINE),
+    change_devices_status(HostId, ?DEVICE_UNKNOWN),
     ok.
 
 %% @private
@@ -417,18 +458,6 @@ code_change(_OldVsn, StateName, State = #state{}, _Extra) ->
 %%% Internal functions
 %%%===================================================================
 
-start_devices(HostId) when is_integer(HostId) ->
-    %% 启动主机相关的device，此时device的状态为离线状态
-    {ok, Devices} = device_bo:get_host_devices(HostId),
-    lists:foreach(fun(DeviceUUID) ->
-        case iot_device_sup:ensured_device_started(DeviceUUID) of
-            {ok, DevicePid} ->
-                iot_device:change_status(DevicePid, ?DEVICE_OFFLINE);
-            {error, Reason} ->
-                lager:notice("[iot_host] start_device: ~p, get error: ~p", [DeviceUUID, Reason])
-        end
-                  end, Devices).
-
 %% 修改设备的状态
 change_devices_status(HostId, NewStatus) when is_integer(HostId), is_integer(NewStatus) ->
     {ok, Devices} = device_bo:get_host_devices(HostId),

config/sys-dev.config

@@ -14,6 +14,10 @@
       {backlog, 10240}
     ]},
 
+    {udp_server, [
+      {port, 18080}
+    ]},
+
     %% 目标服务器地址
     {emqx_server, [
       {host, {39, 98, 184, 67}},

config/sys-prod.config

@@ -14,6 +14,10 @@
       {backlog, 10240}
     ]},
 
+    {udp_server, [
+      {port, 18080}
+    ]},
+
     %% 目标服务器地址
     %{emqx_server, [
     %  {host, {39, 98, 184, 67}},