feat: monitor api, TODO: test suite

apps/emqx_dashboard/include/emqx_dashboard.hrl

@@ -39,7 +39,19 @@
 
 -define(DASHBOARD_SHARD, emqx_dashboard_shard).
 
--record(mqtt_collect, {
+%% 10 seconds
-    timestamp :: integer(),
+-define(DEFAULT_SAMPLE_INTERVAL, 10).
-    collect
+
-    }).
+-define(DELTA_SAMPLER_LIST,
+    [ received
+    , received_bytes
+    , sent
+    , sent_bytes
+    , dropped
+    ]).
+
+-define(SAMPLER_LIST,
+    [ subscriptions
+    , routes
+    , connections
+    ] ++ ?DELTA_SAMPLER_LIST).

apps/emqx_dashboard/src/emqx_dashboard.erl

@@ -92,11 +92,12 @@ stop_listeners() ->
 %% internal
 
 apps() ->
-    [App || {App, _, _} <- application:loaded_applications(),
+    [emqx_dashboard].
-        case re:run(atom_to_list(App), "^emqx") of
+    % [App || {App, _, _} <- application:loaded_applications(),
-            {match,[{0,4}]} -> true;
+    %     case re:run(atom_to_list(App), "^emqx") of
-            _ -> false
+    %         {match,[{0,4}]} -> true;
-        end].
+    %         _ -> false
+    %     end].
 
 listeners() ->
     [begin

apps/emqx_dashboard/src/emqx_dashboard_collection.erl

@@ -1,191 +0,0 @@
-%%--------------------------------------------------------------------
-%% Copyright (c) 2019-2022 EMQ Technologies Co., Ltd. All Rights Reserved.
-%%--------------------------------------------------------------------
-
--module(emqx_dashboard_collection).
-
--behaviour(gen_server).
-
--include("emqx_dashboard.hrl").
--include_lib("stdlib/include/ms_transform.hrl").
-
--export([ start_link/0
-        ]).
-
--export([ init/1
-        , handle_call/3
-        , handle_cast/2
-        , handle_info/2
-        , terminate/2
-        , code_change/3
-        ]).
-
--export([get_collect/0, select_data/0]).
-
--export([get_universal_epoch/0]).
-
--boot_mnesia({mnesia, [boot]}).
-
-%% Mnesia bootstrap
--export([mnesia/1]).
-
--define(APP, emqx_dashboard).
-
--define(DEFAULT_INTERVAL, 10). %% seconds
-
--define(COLLECT, {[],[],[]}).
-
--define(CLEAR_INTERVAL, 86400000).
-
--define(EXPIRE_INTERVAL, 86400000 * 7).
-
-mnesia(boot) ->
-    ok = mria:create_table(?TAB_COLLECT, [
-        {type, set},
-        {local_content, true},
-        {storage, disc_copies},
-        {record_name, mqtt_collect},
-        {attributes, record_info(fields, mqtt_collect)}]).
-
-start_link() ->
-    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
-
-get_collect() -> gen_server:call(whereis(?MODULE), get_collect).
-
--spec select_data() -> [#mqtt_collect{}].
-select_data() ->
-    Time = emqx_dashboard_collection:get_universal_epoch() - 7200000,
-    ets:select(?TAB_COLLECT, [{{mqtt_collect,'$1','$2'}, [{'>', '$1', Time}], ['$_']}]).
-
-init([]) ->
-    timer(next_interval(), collect),
-    timer(get_today_remaining_seconds(), clear_expire_data),
-    ExpireInterval = emqx_conf:get([dashboard, monitor, interval], ?EXPIRE_INTERVAL),
-    State = #{
-        count => count(),
-        expire_interval => ExpireInterval,
-        collect => ?COLLECT,
-        temp_collect => {0, 0, 0, 0},
-        last_collects => {0, 0, 0}
-    },
-    {ok, State}.
-
-%% @doc every whole interval seconds;
-%% example:
-%% interval is 10s
-%% now 15:01:07 (or 15:07:01 ~ 15:07:10)
-%% next will be 15:01:10, 15:01:20, 15:01:30 ...
-%% ensure all counters in cluster have sync time
-next_interval() ->
-    (1000 * interval()) - (erlang:system_time(millisecond) rem (1000 * interval())) - 1.
-
-interval() ->
-    emqx_conf:get([dashboard, sample_interval], ?DEFAULT_INTERVAL).
-
-count() ->
-    60 div interval().
-
-handle_call(get_collect, _From, State = #{temp_collect := {Received, Sent, _, _}}) ->
-    {reply, {Received, Sent, collect(subscriptions), collect(connections)}, State, hibernate};
-handle_call(_Req, _From, State) ->
-    {reply, ok, State}.
-handle_cast(_Req, State) ->
-    {noreply, State}.
-
-handle_info(collect, State = #{ collect := Collect
-                              , count := 1
-                              , temp_collect := TempCollect
-                              , last_collects := LastCollect}) ->
-    timer(next_interval(), collect),
-    NewLastCollect = flush(collect_all(Collect), LastCollect),
-    TempCollect1 = temp_collect(TempCollect),
-    {noreply, State#{count => count(),
-                     collect => ?COLLECT,
-                     temp_collect => TempCollect1,
-                     last_collects => NewLastCollect}};
-
-handle_info(collect, State = #{count := Count, collect := Collect, temp_collect := TempCollect}) ->
-    timer(next_interval(), collect),
-    TempCollect1 = temp_collect(TempCollect),
-    {noreply, State#{count => Count - 1,
-                     collect => collect_all(Collect),
-                     temp_collect => TempCollect1}, hibernate};
-
-handle_info(clear_expire_data, State = #{expire_interval := ExpireInterval}) ->
-    timer(?CLEAR_INTERVAL, clear_expire_data),
-    T1 = get_universal_epoch(),
-    Spec = ets:fun2ms(fun({_, T, _C} = Data) when (T1 - T) > ExpireInterval -> Data end),
-    Collects = ets:select(?TAB_COLLECT, Spec),
-    lists:foreach(fun(Collect) ->
-        true = ets:delete_object(?TAB_COLLECT, Collect)
-    end, Collects),
-    {noreply, State, hibernate};
-
-handle_info(_Info, State) ->
-    {noreply, State}.
-
-terminate(_Reason, _State) ->
-    ok.
-
-code_change(_OldVsn, State, _Extra) ->
-    {ok, State}.
-
-temp_collect({_, _, Received, Sent}) ->
-    Received1 = collect(received),
-    Sent1 = collect(sent),
-    {(Received1 - Received) div interval(),
-     (Sent1 - Sent) div interval(),
-     Received1,
-     Sent1}.
-
-collect_all({Connection, Route, Subscription}) ->
-    {[collect(connections) | Connection],
-     [collect(routes) | Route],
-     [collect(subscriptions) | Subscription]}.
-
-collect(connections) ->
-    emqx_stats:getstat('connections.count');
-collect(routes) ->
-    emqx_stats:getstat('routes.count');
-collect(subscriptions) ->
-    emqx_stats:getstat('subscriptions.count');
-collect(received) ->
-    emqx_metrics:val('messages.received');
-collect(sent) ->
-    emqx_metrics:val('messages.sent');
-collect(dropped) ->
-    emqx_metrics:val('messages.dropped').
-
-flush({Connection, Route, Subscription}, {Received0, Sent0, Dropped0}) ->
-    Received = collect(received),
-    Sent = collect(sent),
-    Dropped = collect(dropped),
-    Collect = {avg(Connection),
-               avg(Route),
-               avg(Subscription),
-               diff(Received, Received0),
-               diff(Sent, Sent0),
-               diff(Dropped, Dropped0)},
-    Ts = get_universal_epoch(),
-    {atomic, ok} = mria:transaction(mria:local_content_shard(),
-                                    fun mnesia:write/3,
-                                    [ ?TAB_COLLECT
-                                    , #mqtt_collect{timestamp = Ts, collect = Collect}
-                                    , write]),
-    {Received, Sent, Dropped}.
-
-avg(Items) ->
-    lists:sum(Items) div count().
-
-diff(Item0, Item1) ->
-    Item0 - Item1.
-
-timer(Secs, Msg) ->
-    erlang:send_after(Secs, self(), Msg).
-
-get_today_remaining_seconds() ->
-    ?CLEAR_INTERVAL - (get_universal_epoch() rem ?CLEAR_INTERVAL).
-
-get_universal_epoch() ->
-    (calendar:datetime_to_gregorian_seconds(calendar:universal_time()) -
-        calendar:datetime_to_gregorian_seconds({{1970,1,1}, {0,0,0}})).

apps/emqx_dashboard/src/emqx_dashboard_monitor.erl

@@ -16,7 +16,7 @@
 
 -module(emqx_dashboard_monitor).
 
--include_lib("stdlib/include/ms_transform.hrl").
+-include("emqx_dashboard.hrl").
 
 -behaviour(gen_server).
 
@@ -34,15 +34,15 @@
 
 -export([ mnesia/1]).
 
--export([ samples/0
+-export([ samplers/0
-        , samples/1
+        , samplers/1
-        , aggregate_samplers/0
+        , samplers/2
         ]).
 
--define(TAB, ?MODULE).
+%% for rpc
+-export([ do_samples/1]).
 
-%% 10 seconds
+-define(TAB, ?MODULE).
--define(DEFAULT_INTERVAL, 10).
 
 -ifdef(TEST).
 %% for test
@@ -70,21 +70,6 @@
     data :: map()
     }).
 
-
--define(DELTA_LIST,
-    [ received
-    , received_bytes
-    , sent
-    , sent_bytes
-    , dropped
-    ]).
-
--define(SAMPLER_LIST,
-    [ subscriptions
-    , routes
-    , connections
-    ] ++ ?DELTA_LIST).
-
 mnesia(boot) ->
     ok = mria:create_table(?TAB, [
         {type, set},
@@ -93,17 +78,26 @@ mnesia(boot) ->
         {record_name, emqx_monit},
         {attributes, record_info(fields, emqx_monit)}]).
 
-aggregate_samplers() ->
+samplers() ->
-    [#{node => Node, data => samples(Node)} || Node <- mria_mnesia:cluster_nodes(running)].
+    samplers(all).
 
-samples() ->
+samplers(NodeOrCluster) ->
-    All = [samples(Node) || Node <- mria_mnesia:cluster_nodes(running)],
+    format(do_samples(NodeOrCluster)).
-    lists:foldl(fun merge_cluster_samplers/2, #{}, All).
 
-samples(Node) when Node == node() ->
+samplers(NodeOrCluster, 0) ->
-    get_data(?DEFAULT_GET_DATA_TIME);
+    samplers(NodeOrCluster);
-samples(Node) ->
+samplers(NodeOrCluster, Latest) ->
-    rpc:call(Node, ?MODULE, ?FUNCTION_NAME, [Node]).
+    case samplers(NodeOrCluster) of
+        {badrpc, Reason} ->
+            {badrpc, Reason};
+        List when is_list(List) ->
+            case erlang:length(List) - Latest of
+                Start when Start > 0 ->
+                    lists:sublist(List, Start, Latest);
+                _ ->
+                    List
+            end
+    end.
 
 %%%===================================================================
 %%% gen_server functions
@@ -147,6 +141,43 @@ code_change(_OldVsn, State = #state{}, _Extra) ->
 %%% Internal functions
 %%%===================================================================
 
+do_samples(all) ->
+    Fun =
+        fun(Node, All) ->
+            case do_samples(Node) of
+                {badrpc, Reason} ->
+                    {badrpc, {Node, Reason}};
+                NodeSamplers ->
+                    merge_cluster_samplers(NodeSamplers, All)
+            end
+        end,
+    lists:foldl(Fun, #{}, mria_mnesia:cluster_nodes(running));
+do_samples(Node) when Node == node() ->
+    get_data(?DEFAULT_GET_DATA_TIME);
+do_samples(Node) ->
+    rpc:call(Node, ?MODULE, ?FUNCTION_NAME, [Node], 5000).
+
+merge_cluster_samplers(Node, Cluster) ->
+    maps:fold(fun merge_cluster_samplers/3, Cluster, Node).
+
+merge_cluster_samplers(TS, NodeData, Cluster) ->
+    case maps:get(TS, Cluster, undefined) of
+        undefined ->
+            Cluster#{TS => NodeData};
+        ClusterData ->
+            Cluster#{TS => count_map(NodeData, ClusterData)}
+    end.
+
+format({badrpc, Reason}) ->
+    {badrpc, Reason};
+format(Data) ->
+    All = maps:fold(fun format/3, [], Data),
+    Compare = fun(#{time_stamp := T1}, #{time_stamp := T2}) -> T1 =< T2 end,
+    lists:sort(Compare, All).
+
+format(TimeStamp, Data, All) ->
+    [Data#{time_stamp => TimeStamp} | All].
+
 sample_timer() ->
     {NextTime, Remaining} = next_interval(),
     erlang:send_after(Remaining, self(), {sample, NextTime}).
@@ -160,7 +191,7 @@ clean_timer() ->
 %%  The monitor will start working at full seconds, as like 00:00:00, 00:00:10, 00:00:20 ...
 %% Ensure that the monitor data of all nodes in the cluster are aligned in time
 next_interval() ->
-    Interval = emqx_conf:get([dashboard, monitor, interval], ?DEFAULT_INTERVAL) * 1000,
+    Interval = emqx_conf:get([dashboard, monitor, interval], ?DEFAULT_SAMPLE_INTERVAL) * 1000,
     Now = erlang:system_time(millisecond),
     NextTime = ((Now div Interval) + 1) * Interval,
     Remaining = NextTime - Now,
@@ -186,7 +217,7 @@ delta(LastData, NowData) ->
             Value = maps:get(Key, NowData) - maps:get(Key, LastData),
             Data#{Key => Value}
         end,
-    lists:foldl(Fun, NowData, ?DELTA_LIST).
+    lists:foldl(Fun, NowData, ?DELTA_SAMPLER_LIST).
 
 store(MonitData) ->
     {atomic, ok} =
@@ -204,28 +235,18 @@ clean() ->
 get_data(PastTime) ->
     Now = erlang:system_time(millisecond),
     ExpiredMS = [{{'_', '$1', '_'}, [{'<', {'-', Now, '$1'}, PastTime}], ['$_']}],
-    format(ets:select(?TAB, ExpiredMS)).
+    internal_format(ets:select(?TAB, ExpiredMS)).
 
-format(List) when is_list(List) ->
+%% To make it easier to do data aggregation
+internal_format(List) when is_list(List) ->
     Fun =
         fun(Data, All) ->
-            maps:merge(format(Data), All)
+            maps:merge(internal_format(Data), All)
         end,
     lists:foldl(Fun, #{}, List);
-format(#emqx_monit{time = Time, data = Data}) ->
+internal_format(#emqx_monit{time = Time, data = Data}) ->
     #{Time => Data}.
 
-merge_cluster_samplers(Node, Cluster) ->
-    maps:fold(fun merge_cluster_samplers/3, Cluster, Node).
-
-merge_cluster_samplers(TS, NodeData, Cluster) ->
-    case maps:get(TS, Cluster, undefined) of
-        undefined ->
-            Cluster#{TS => NodeData};
-        ClusterData ->
-            Cluster#{TS => count_map(NodeData, ClusterData)}
-    end.
-
 count_map(M1, M2) ->
     Fun =
         fun(Key, Map) ->

apps/emqx_dashboard/src/emqx_dashboard_monitor_api.erl

@@ -5,308 +5,105 @@
 -module(emqx_dashboard_monitor_api).
 
 -include("emqx_dashboard.hrl").
+-include_lib("typerefl/include/types.hrl").
 
 -behaviour(minirest_api).
 
--import(emqx_mgmt_util, [schema/2]).
+-export([ api_spec/0]).
--export([api_spec/0]).
 
--export([ monitor/2
+-export([ paths/0
-        , counters/2
+        , schema/1
-        , monitor_nodes/2
+        , fields/1
-        , monitor_nodes_counters/2
-        , current_counters/2
         ]).
 
--export([ sampling/1
+-export([ monitor/2]).
-        , sampling/2
-        ]).
 
--define(COUNTERS, [ connection
+-define(SAMPLERS,
-                  , route
+    [ connection
-                  , subscriptions
+    , route
-                  , received
+    , subscriptions
-                  , sent
+    , received
-                  , dropped]).
+    , sent
-
+    , dropped
--define(EMPTY_COLLECTION, {0, 0, 0, 0}).
+    ]).
 
 api_spec() ->
-    {[ monitor_api()
+    emqx_dashboard_swagger:spec(?MODULE, #{check_schema => true, translate_body => true}).
-     , monitor_nodes_api()
-     , monitor_nodes_counters_api()
-     , monitor_counters_api()
-     , monitor_current_api()
-    ],
-    []}.
 
-monitor_api() ->
+paths() ->
-    Metadata = #{
+    [ "/monitor"
+    , "/monitor/nodes/:node"
+    ].
+
+schema("/monitor") ->
+    #{
+        'operationId' => monitor,
         get => #{
-            description => <<"List monitor data">>,
+            description => <<"List monitor data.">>,
             parameters => [
-                #{
+                {latest, hoconsc:mk(integer(), #{in => query, required => false, example => 1000})}
-                    name => aggregate,
-                    in => query,
-                    required => false,
-                    schema => #{type => boolean}
-                }
             ],
             responses => #{
-                <<"200">> => schema(counters_schema(), <<"Monitor count data">>)}}},
+                200 => hoconsc:mk(hoconsc:array(hoconsc:ref(sampler)), #{}),
-    {"/monitor", Metadata, monitor}.
+                400 => emqx_dashboard_swagger:error_codes(['BAD_RPC'], <<"Bad RPC">>)
-
+            }
-monitor_nodes_api() ->
+        }
-    Metadata = #{
-        get => #{
-            description => <<"List monitor data">>,
-            parameters => [path_param_node()],
-            responses => #{
-                <<"200">> => schema(counters_schema(), <<"Monitor count data in node">>)}}},
-    {"/monitor/nodes/:node", Metadata, monitor_nodes}.
-
-monitor_nodes_counters_api() ->
-    Metadata = #{
-        get => #{
-            description => <<"List monitor data">>,
-            parameters => [
-                path_param_node(),
-                path_param_counter()
-            ],
-            responses => #{
-                <<"200">> => schema(counter_schema(), <<"Monitor single count data in node">>)}}},
-    {"/monitor/nodes/:node/counters/:counter", Metadata, monitor_nodes_counters}.
-
-monitor_counters_api() ->
-    Metadata = #{
-        get => #{
-            description => <<"List monitor data">>,
-            parameters => [
-                path_param_counter()
-            ],
-            responses => #{
-                <<"200">> =>
-                    schema(counter_schema(), <<"Monitor single count data">>)}}},
-    {"/monitor/counters/:counter", Metadata, counters}.
-monitor_current_api() ->
-    Metadata = #{
-        get => #{
-            description => <<"Current monitor data">>,
-            responses => #{
-                <<"200">> => schema(current_counters_schema(), <<"Current monitor data">>)}}},
-    {"/monitor/current", Metadata, current_counters}.
-
-path_param_node() ->
-    #{
-        name => node,
-        in => path,
-        required => true,
-        schema => #{type => string},
-        example => node()
-    }.
-
-path_param_counter() ->
-    #{
-        name => counter,
-        in => path,
-        required => true,
-        schema => #{type => string, enum => ?COUNTERS},
-        example => hd(?COUNTERS)
-    }.
-
-current_counters_schema() ->
-    #{
-        type => object,
-        properties => #{
-            connection => #{type => integer},
-            sent => #{type => integer},
-            received => #{type => integer},
-            subscription => #{type => integer}}
-    }.
-
-counters_schema() ->
-    Fun =
-        fun(K, M) ->
-            maps:merge(M, counters_schema(K))
-        end,
-    Properties = lists:foldl(Fun, #{}, ?COUNTERS),
-    #{
-        type => object,
-        properties => Properties
-    }.
-
-counters_schema(Name) ->
-    #{Name => counter_schema()}.
-counter_schema() ->
-    #{
-        type => array,
-        items => #{
-            type => object,
-            properties => #{
-                timestamp => #{
-                    type => integer,
-                    description => <<"Millisecond">>},
-                count => #{
-                    type => integer}}}}.
-%%%==============================================================================================
-%% parameters trans
-monitor(get, #{query_string := Qs}) ->
-    Aggregate = maps:get(<<"aggregate">>, Qs, <<"false">>),
-    {200, list_collect(Aggregate)}.
-
-monitor_nodes(get, #{bindings := #{node := Node}}) ->
-    lookup([{<<"node">>, Node}]).
-
-monitor_nodes_counters(get, #{bindings := #{node := Node, counter := Counter}}) ->
-    lookup([{<<"node">>, Node}, {<<"counter">>, Counter}]).
-
-counters(get, #{bindings := #{counter := Counter}}) ->
-    lookup([{<<"counter">>, Counter}]).
-
-current_counters(get, _Params) ->
-    Data = [get_collect(Node) || Node <- mria_mnesia:running_nodes()],
-    Nodes = length(mria_mnesia:running_nodes()),
-    {Received, Sent, Sub, Conn} = format_current_metrics(Data),
-    Response = #{
-        nodes           => Nodes,
-        received        => Received,
-        sent            => Sent,
-        subscription    => Sub,
-        connection      => Conn
-    },
-    {200, Response}.
-
-format_current_metrics(Collects) ->
-    format_current_metrics(Collects, ?EMPTY_COLLECTION).
-format_current_metrics([], Acc) ->
-    Acc;
-format_current_metrics([{Received, Sent, Sub, Conn} | Collects],
-        {Received1, Sent1, Sub1, Conn1}) ->
-    format_current_metrics(Collects,
-        {Received1 + Received, Sent1 + Sent, Sub1 + Sub, Conn1 + Conn}).
-
-
-%%%==============================================================================================
-%% api apply
-
-lookup(Params) ->
-    Fun =
-        fun({K,V}, M) ->
-            maps:put(binary_to_atom(K, utf8), binary_to_atom(V, utf8), M)
-        end,
-    lookup_(lists:foldl(Fun, #{}, Params)).
-
-lookup_(#{node := Node, counter := Counter}) ->
-    Data = hd(maps:values(sampling(Node, Counter))),
-    {200, Data};
-lookup_(#{node := Node}) ->
-    {200, sampling(Node)};
-lookup_(#{counter := Counter}) ->
-    CounterData = merger_counters([sampling(Node, Counter) || Node <- mria_mnesia:running_nodes()]),
-    Data = hd(maps:values(CounterData)),
-    {200, Data}.
-
-list_collect(Aggregate) ->
-    case Aggregate of
-        <<"true">> ->
-            [maps:put(node, Node, sampling(Node)) || Node <- mria_mnesia:running_nodes()];
-        _ ->
-            Counters = [sampling(Node) || Node <- mria_mnesia:running_nodes()],
-            merger_counters(Counters)
-    end.
-
-get_collect(Node) ->
-    case emqx_dashboard_proto_v1:get_collect(Node) of
-        {badrpc, _Reason} -> ?EMPTY_COLLECTION;
-        Res -> Res
-    end.
-
-merger_counters(ClusterCounters) ->
-    lists:foldl(fun merger_node_counters/2, #{}, ClusterCounters).
-
-merger_node_counters(NodeCounters, Counters) ->
-    maps:fold(fun merger_counter/3, Counters, NodeCounters).
-
-merger_counter(Key, Counters, Res) ->
-    case maps:get(Key, Res, undefined) of
-        undefined ->
-            Res#{Key => Counters};
-        OldCounters ->
-            NCounters = lists:foldl(fun merger_counter/2, OldCounters, Counters),
-            Res#{Key => NCounters}
-    end.
-
-merger_counter(#{timestamp := Timestamp, count := Value}, Counters) ->
-    Comparison =
-        fun(Counter) ->
-            case maps:get(timestamp, Counter) =:= Timestamp of
-                true ->
-                    Count = maps:get(count, Counter),
-                    {ok, Counter#{count => Count + Value}};
-                false ->
-                    ignore
-            end
-        end,
-    key_replace(Counters, Comparison, #{timestamp => Timestamp, count => Value}).
-
-key_replace(List, Comparison, Default) ->
-    key_replace(List, List, Comparison, Default).
-
-key_replace([], All, _Comparison, Default) ->
-    [Default | All];
-
-key_replace([Term | List], All, Comparison, Default) ->
-    case Comparison(Term) of
-        {ok, NTerm} ->
-            Tail = [NTerm | List],
-            Header = lists:sublist(All, length(All) - length(Tail)),
-            lists:append(Header, Tail);
-        _ ->
-            key_replace(List, All, Comparison, Default)
-    end.
-
-sampling(Node) ->
-    Data = emqx_dashboard_proto_v1:select_data(Node),
-    format(lists:sort(Data)).
-
-sampling(Node, Counter) ->
-    Data = emqx_dashboard_proto_v1:select_data(Node),
-    format_single(lists:sort(Data), Counter).
-
-format(Collects) ->
-    format(Collects, {[],[],[],[],[],[]}).
-format([], {Connection, Route, Subscription, Received, Sent, Dropped}) ->
-    #{
-        connection      => add_key(Connection),
-        route           => add_key(Route),
-        subscriptions   => add_key(Subscription),
-        received        => add_key(Received),
-        sent            => add_key(Sent),
-        dropped         => add_key(Dropped)
     };
 
-format([#mqtt_collect{timestamp = Ts, collect = {C, R, S, Re, S1, D}} | Collects],
+schema("/monitor/nodes/:node") ->
-       {Connection, Route, Subscription, Received, Sent, Dropped}) ->
+    #{
-    format(Collects, {[[Ts, C]  | Connection],
+        'operationId' => monitor,
-                      [[Ts, R]  | Route],
+        get => #{
-                      [[Ts, S]  | Subscription],
+            description => <<"List the monitor data on the node.">>,
-                      [[Ts, Re] | Received],
+            parameters => [
-                      [[Ts, S1] | Sent],
+                {node, hoconsc:mk(binary(), #{in => path, required => true, example => node()})},
-                      [[Ts, D]  | Dropped]}).
+                {latest, hoconsc:mk(integer(), #{in => query, required => false, example => 1000})}
-add_key(Collects) ->
+            ],
-    lists:reverse([#{timestamp => Ts * 1000, count => C} || [Ts, C] <- Collects]).
+            responses => #{
+                200 => hoconsc:mk(hoconsc:array(hoconsc:ref(sampler)), #{}),
+                400 => emqx_dashboard_swagger:error_codes(['BAD_RPC'], <<"Bad RPC">>)
+            }
+        }
+    }.
 
-format_single(Collects, Counter) ->
+fields(sampler) ->
-    #{Counter => format_single(Collects, counter_index(Counter), [])}.
+    Samplers =
-format_single([], _Index, Acc) ->
+        [{SamplerName, hoconsc:mk(integer(), #{desc => sampler_desc(SamplerName)})}
-    lists:reverse(Acc);
+        || SamplerName <- ?SAMPLER_LIST],
-format_single([#mqtt_collect{timestamp = Ts, collect = Collect} | Collects], Index, Acc) ->
+    [{time_stamp, hoconsc:mk(integer(), #{desc => <<"Timestamp">>})} | Samplers].
-    format_single(Collects, Index,
-        [#{timestamp => Ts * 1000, count => erlang:element(Index, Collect)} | Acc]).
 
-counter_index(connection)    -> 1;
+%% -------------------------------------------------------------------------------------------------
-counter_index(route)         -> 2;
+%% API
-counter_index(subscriptions) -> 3;
+
-counter_index(received)      -> 4;
+monitor(get, #{query_string := QS, bindings := Bindings}) ->
-counter_index(sent)          -> 5;
+    Latest = maps:get(<<"latest">>, QS, 0),
-counter_index(dropped)       -> 6.
+    Node = binary_to_atom(maps:get(node, Bindings, <<"all">>)),
+    case emqx_dashboard_monitor:samplers(Node, Latest) of
+        {badrpc, {Node, Reason}} ->
+            Message = list_to_binary(io_lib:format("Bad node ~p, rpc failed ~p", [Node, Reason])),
+            {400, 'BAD_RPC', Message};
+        Samplers ->
+            {200, Samplers}
+    end.
+
+%% -------------------------------------------------------------------------------------------------
+%% Internal
+
+sampler_desc(received)       -> sampler_desc_format("Received messages ");
+sampler_desc(received_bytes) -> sampler_desc_format("Received bytes ");
+sampler_desc(sent)           -> sampler_desc_format("Sent messages ");
+sampler_desc(sent_bytes)     -> sampler_desc_format("Sent bytes ");
+sampler_desc(dropped)        -> sampler_desc_format("Dropped messages ");
+sampler_desc(subscriptions) ->
+    <<"Subscriptions at the time of sampling."
+    " Can only represent the approximate state">>;
+sampler_desc(routes) ->
+    <<"Routes at the time of sampling."
+    " Can only represent the approximate state">>;
+sampler_desc(connections) ->
+    <<"Connections at the time of sampling."
+    " Can only represent the approximate state">>.
+
+sampler_desc_format(Format) ->
+    Interval = emqx_conf:get([dashboard, monitor, interval], ?DEFAULT_SAMPLE_INTERVAL),
+    list_to_binary(io_lib:format(Format ++ "last ~p seconds", [Interval])).

apps/emqx_dashboard/src/proto/emqx_dashboard_proto_v1.erl

@@ -20,8 +20,7 @@
 
 -export([ introduced_in/0
 
-        , get_collect/1
+        , samplers/1
-        , select_data/1
         ]).
 
 -include("emqx_dashboard.hrl").
@@ -30,11 +29,6 @@
 introduced_in() ->
     "5.0.0".
 
--spec get_collect(node()) -> _.
+-spec samplers(node()) -> list(map()) | emqx_rpc:badrpc().
-get_collect(Node) ->
+samplers(Node) ->
-    rpc:call(Node, emqx_dashboard_collection, get_collect, []).
+    rpc:call(Node, emqx_dashboard_monitor, samplers, [Node]).
-
--spec select_data(node()) -> [#mqtt_collect{}]
-                           | emqx_rpc:badrpc().
-select_data(Node) ->
-    rpc:call(Node, emqx_dashboard_collection, select_data, []).

apps/emqx_dashboard/test/emqx_dashboard_monitor_api_SUITE.erl

@@ -27,95 +27,14 @@
 all() ->
     emqx_common_test_helpers:all(?MODULE).
 
-init_per_testcase(t_badrpc_collect, Config) ->
-    Cluster = cluster_specs(2),
-    Apps = [emqx_modules, emqx_dashboard],
-    Nodes = [N1, N2] =  lists:map(fun(Spec) -> start_slave(Spec, Apps) end, Cluster),
-    %% form the cluster
-    ok = rpc:call(N2, mria, join, [N1]),
-    %% Wait until all nodes are healthy:
-    [rpc:call(Node, mria_rlog, wait_for_shards, [[?DASHBOARD_SHARD], 5000])
-     || Node <- Nodes],
-    [ {nodes, Nodes}
-    , {apps, Apps}
-    | Config];
 init_per_testcase(_, Config) ->
     Config.
 
-end_per_testcase(t_badrpc_collect, Config) ->
-    Apps = ?config(apps, Config),
-    Nodes = ?config(nodes, Config),
-    lists:foreach(fun(Node) -> stop_slave(Node, Apps) end, Nodes),
-    ok;
 end_per_testcase(_, _Config) ->
     ok.
 
-t_badrpc_collect(Config) ->
-    [N1, N2] = ?config(nodes, Config),
-    %% simulate badrpc on one node
-    ok = rpc:call(N2, meck, new, [emqx_dashboard_collection, [no_history, no_link]]),
-    %% we don't mock the `emqx_dashboard_collection:get_collect/0' to
-    %% provoke the `badrpc' error.
-    ?assertMatch(
-       {200, #{nodes := 2}},
-       rpc:call(N1, emqx_dashboard_monitor_api, current_counters, [get, #{}])),
-    ok = rpc:call(N2, meck, unload, [emqx_dashboard_collection]),
-    ok.
 
 %%------------------------------------------------------------------------------
 %% Internal functions
 %%------------------------------------------------------------------------------
 
-cluster_specs(NumNodes) ->
-    BaseGenRpcPort = 9000,
-    Specs0 = [#{ name => node_name(N)
-               , num => N
-               }
-              || N <- lists:seq(1, NumNodes)],
-    GenRpcPorts = maps:from_list([{node_id(Name), {tcp, BaseGenRpcPort + N}}
-                                  || #{name := Name, num := N} <- Specs0]),
-    [ Spec#{env => [ {gen_rpc, tcp_server_port, BaseGenRpcPort + N}
-                   , {gen_rpc, client_config_per_node, {internal, GenRpcPorts}}
-                   ]}
-      || Spec = #{num := N} <- Specs0].
-
-node_name(N) ->
-    list_to_atom("n" ++ integer_to_list(N)).
-
-node_id(Name) ->
-    list_to_atom(lists:concat([Name, "@", host()])).
-
-start_slave(Spec = #{ name := Name}, Apps) ->
-    CommonBeamOpts = "+S 1:1 ", % We want VMs to only occupy a single core
-    {ok, Node} = slave:start_link(host(), Name, CommonBeamOpts ++ ebin_path()),
-    setup_node(Node, Spec, Apps),
-    Node.
-
-stop_slave(Node, Apps) ->
-    ok = rpc:call(Node, emqx_common_test_helpers, start_apps, [Apps]),
-    slave:stop(Node).
-
-host() ->
-    [_, Host] = string:tokens(atom_to_list(node()), "@"), Host.
-
-ebin_path() ->
-    string:join(["-pa" | lists:filter(fun is_lib/1, code:get_path())], " ").
-
-is_lib(Path) ->
-    string:prefix(Path, code:lib_dir()) =:= nomatch.
-
-setenv(Node, Env) ->
-    [rpc:call(Node, application, set_env, [App, Key, Val]) || {App, Key, Val} <- Env].
-
-setup_node(Node, _Spec = #{env := Env}, Apps) ->
-    %% load these before starting ekka and such
-    [rpc:call(Node, application, load, [App]) || App <- [gen_rpc, emqx_conf, emqx]],
-    setenv(Node, Env),
-    EnvHandler =
-        fun(emqx) ->
-                application:set_env(emqx, boot_modules, [router, broker]);
-           (_) ->
-                ok
-        end,
-    ok = rpc:call(Node, emqx_common_test_helpers, start_apps, [Apps, EnvHandler]),
-    ok.