ekfa/apps/efka/src/websocket_server/ws_channel.erl
2025-08-27 15:50:10 +08:00

188 lines
8.3 KiB
Erlang

%%%-------------------------------------------------------------------
%%% @author licheng5
%%% @copyright (C) 2021, <COMPANY>
%%% @doc
%%%
%%% @end
%%% Created : 11. 1月 2021 上午12:17
%%%-------------------------------------------------------------------
-module(ws_channel).
-author("licheng5").
-include("efka_service.hrl").
%% API
-export([init/2]).
-export([websocket_init/1, websocket_handle/2, websocket_info/2, terminate/3]).
%% 最大的等待时间
-define(PENDING_TIMEOUT, 10 * 1000).
-record(state, {
packet_id = 1,
service_id :: undefined | binary(),
service_pid :: undefined | pid(),
is_registered = false :: boolean(),
%% 请求响应的对应关系, #{packet_id => {ReceiverPid, Ref}}; 自身的inflight需要超时逻辑处理
inflight = #{}
}).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% 逻辑处理方法
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
init(Req, Opts) ->
{cowboy_websocket, Req, Opts}.
websocket_init(_State) ->
lager:debug("[ws_channel] get a new connection"),
%% 初始状态为true
{ok, #state{packet_id = 1}}.
websocket_handle({binary, <<?PACKET_REQUEST, Data/binary>>}, State) ->
Request = jiffy:decode(Data, [return_maps]),
handle_request(Request, State);
%% 处理micro-client:response => efka 的响应
websocket_handle({binary, <<?PACKET_RESPONSE:8, Data/binary>>}, State = #state{inflight = Inflight}) ->
Resp = jiffy:decode(Data, [return_maps]),
{PacketId, Reply} = case Resp of
#{<<"id">> := Id, <<"result">> := Result} ->
{Id, {ok, Result}};
#{<<"id">> := Id, <<"error">> := #{<<"code">> := _Code, <<"message">> := Error}} ->
{Id, {error, Error}}
end,
case maps:take(PacketId, Inflight) of
error ->
lager:warning("[tcp_channel] get unknown publish response message: ~p, packet_id: ~p", [Resp, PacketId]),
{ok, State};
{{ReceiverPid, Ref}, NInflight} ->
case is_pid(ReceiverPid) andalso is_process_alive(ReceiverPid) of
true ->
ReceiverPid ! {channel_reply, Ref, Reply};
false ->
lager:warning("[tcp_channel] get publish response message: ~p, packet_id: ~p, but receiver_pid is deaded", [Resp, PacketId])
end,
{ok, State#state{inflight = NInflight}}
end;
websocket_handle(Info, State) ->
lager:error("[ws_channel] get a unknown message: ~p, channel will closed", [Info]),
{stop, State}.
websocket_info({push_config, Ref, ReceiverPid, ConfigJson}, State = #state{packet_id = PacketId, inflight = Inflight}) ->
PushConfig = #{<<"id">> => PacketId, <<"method">> => <<"push_config">>, <<"params">> => #{<<"config">> => ConfigJson}},
Packet = jiffy:encode(PushConfig, [force_utf8]),
Reply = <<?PACKET_PUSH:8, Packet/binary>>,
erlang:start_timer(?PENDING_TIMEOUT, self(), {pending_timeout, PacketId}),
{reply, {binary, Reply}, State#state{packet_id = gen_channel:next_packet_id(PacketId), inflight = maps:put(PacketId, {ReceiverPid, Ref}, Inflight)}};
%% 远程调用
websocket_info({invoke, Ref, ReceiverPid, Payload}, State = #state{packet_id = PacketId, inflight = Inflight}) ->
PushConfig = #{<<"id">> => PacketId, <<"method">> => <<"invoke">>, <<"params">> => #{<<"payload">> => Payload}},
Packet = jiffy:encode(PushConfig, [force_utf8]),
Reply = <<?PACKET_PUSH:8, Packet/binary>>,
erlang:start_timer(?PENDING_TIMEOUT, self(), {pending_timeout, PacketId}),
{reply, {binary, Reply}, State#state{packet_id = gen_channel:next_packet_id(PacketId), inflight = maps:put(PacketId, {ReceiverPid, Ref}, Inflight)}};
%% 订阅的消息
websocket_info({topic_broadcast, Topic, Content}, State = #state{}) ->
Packet = jiffy:encode(#{<<"topic">> => Topic, <<"content">> => Content}, [force_utf8]),
Reply = <<?PACKET_PUB:8, Packet/binary>>,
{reply, {binary, Reply}, State};
%% 超时逻辑处理
websocket_info({timeout, _, {pending_timeout, Id}}, State = #state{inflight = Inflight}) ->
case maps:take(Id, Inflight) of
error ->
{ok, State};
{{ReceiverPid, Ref}, NInflight} ->
case is_pid(ReceiverPid) andalso is_process_alive(ReceiverPid) of
true ->
ReceiverPid ! {channel_reply, Ref, {error, <<"timeout">>}};
false ->
ok
end,
{ok, State#state{inflight = NInflight}}
end;
%% service进程关闭
websocket_info({'DOWN', _Ref, process, ServicePid, Reason}, State = #state{service_pid = ServicePid}) ->
lager:debug("[tcp_channel] service_pid: ~p, exited: ~p", [ServicePid, Reason]),
{stop, State#state{service_pid = undefined}};
websocket_info({timeout, _, {stop, Reason}}, State) ->
lager:debug("[ws_channel] the channel will be closed with reason: ~p", [Reason]),
{stop, State};
%% 处理关闭信号
websocket_info({stop, Reason}, State) ->
lager:debug("[ws_channel] the channel will be closed with reason: ~p", [Reason]),
{stop, State};
%% 处理其他未知消息
websocket_info(Info, State) ->
lager:debug("[ws_channel] channel get unknown info: ~p", [Info]),
{ok, State}.
%% 进程关闭事件
terminate(Reason, _Req, State) ->
lager:debug("[ws_channel] channel close with reason: ~p, state is: ~p", [Reason, State]),
ok.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% helper methods
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% 注册
handle_request(#{<<"id">> := Id, <<"method">> := <<"register">>, <<"params">> := #{<<"service_id">> := ServiceId}}, State) ->
case efka_service:get_pid(ServiceId) of
undefined ->
lager:warning("[efka_tcp_channel] service_id: ~p, not running", [ServiceId]),
Packet = gen_channel:json_error(Id, -1, <<"service not running">>),
Reply = <<?PACKET_RESPONSE:8, Packet/binary>>,
delay_stop(10, normal),
{reply, {binary, Reply}, State};
ServicePid when is_pid(ServicePid) ->
case efka_service:attach_channel(ServicePid, self()) of
ok ->
Packet = gen_channel:json_result(Id, <<"ok">>),
erlang:monitor(process, ServicePid),
Reply = <<?PACKET_RESPONSE:8, Packet/binary>>,
{reply, {binary, Reply}, State#state{service_id = ServiceId, service_pid = ServicePid, is_registered = true}};
{error, Error} ->
lager:warning("[efka_tcp_channel] service_id: ~p, attach_channel get error: ~p", [ServiceId, Error]),
Packet = gen_channel:json_error(Id, -1, Error),
Reply = <<?PACKET_RESPONSE:8, Packet/binary>>,
delay_stop(10, normal),
{reply, {binary, Reply}, State}
end
end;
%% 请求参数
handle_request(#{<<"id">> := Id, <<"method">> := <<"request_config">>}, State = #state{service_pid = ServicePid, is_registered = true}) ->
{ok, ConfigJson} = efka_service:request_config(ServicePid),
Packet = gen_channel:json_result(Id, ConfigJson),
Reply = <<?PACKET_RESPONSE:8, Packet/binary>>,
{reply, {binary, Reply}, State};
%% 数据项
handle_request(#{<<"id">> := 0, <<"method">> := <<"metric_data">>,
<<"params">> := #{<<"device_uuid">> := DeviceUUID, <<"route_key">> := RouteKey, <<"metric">> := Metric}}, State = #state{service_pid = ServicePid, is_registered = true}) ->
efka_service:metric_data(ServicePid, DeviceUUID, RouteKey, Metric),
{ok, State};
%% Event事件
handle_request(#{<<"id">> := 0, <<"method">> := <<"event">>, <<"params">> := #{<<"event_type">> := EventType, <<"body">> := Body}}, State = #state{service_pid = ServicePid, is_registered = true}) ->
efka_service:send_event(ServicePid, EventType, Body),
{ok, State};
%% 订阅事件
handle_request(#{<<"id">> := 0, <<"method">> := <<"subscribe">>, <<"params">> := #{<<"topic">> := Topic}}, State = #state{is_registered = true}) ->
efka_subscription:subscribe(Topic, self()),
{ok, State}.
delay_stop(Timeout, Reason) when is_integer(Timeout) ->
erlang:start_timer(Timeout, self(), {stop, Reason}).