feat(cluster link api): add status to responses

Fixes https://emqx.atlassian.net/browse/EMQX-12627

apps/emqx/priv/bpapi.versions

@@ -10,6 +10,7 @@
 {emqx_bridge,5}.
 {emqx_bridge,6}.
 {emqx_broker,1}.
+{emqx_cluster_link,1}.
 {emqx_cm,1}.
 {emqx_cm,2}.
 {emqx_cm,3}.

apps/emqx_cluster_link/src/emqx_cluster_link_api.erl

@@ -8,10 +8,14 @@
 -include_lib("hocon/include/hoconsc.hrl").
 -include_lib("emqx/include/http_api.hrl").
 -include_lib("emqx_utils/include/emqx_utils_api.hrl").
+-include_lib("emqx_resource/include/emqx_resource.hrl").
+-include_lib("emqx/include/logger.hrl").
 
 -export([
     api_spec/0,
     paths/0,
+    namespace/0,
+    fields/1,
     schema/1
 ]).
 
@@ -23,6 +27,10 @@
 -define(CONF_PATH, [cluster, links]).
 -define(TAGS, [<<"Cluster">>]).
 
+-type cluster_name() :: binary().
+
+namespace() -> "cluster_link".
+
 api_spec() ->
     emqx_dashboard_swagger:spec(?MODULE, #{check_schema => true}).
 
@@ -40,7 +48,7 @@ schema("/cluster/links") ->
                 description => "Get cluster links configuration",
                 tags => ?TAGS,
                 responses =>
-                    #{200 => links_config_schema()}
+                    #{200 => links_config_schema_response()}
             },
         post =>
             #{
@@ -49,7 +57,7 @@ schema("/cluster/links") ->
                 'requestBody' => link_config_schema(),
                 responses =>
                     #{
-                        200 => link_config_schema(),
+                        200 => link_config_schema_response(),
                         400 =>
                             emqx_dashboard_swagger:error_codes(
                                 [?BAD_REQUEST, ?ALREADY_EXISTS],
@@ -68,7 +76,7 @@ schema("/cluster/links/:name") ->
                 parameters => [param_path_name()],
                 responses =>
                     #{
-                        200 => link_config_schema(),
+                        200 => link_config_schema_response(),
                         404 => emqx_dashboard_swagger:error_codes(
                             [?NOT_FOUND], <<"Cluster link not found">>
                         )
@@ -95,7 +103,7 @@ schema("/cluster/links/:name") ->
                 'requestBody' => update_link_config_schema(),
                 responses =>
                     #{
-                        200 => link_config_schema(),
+                        200 => link_config_schema_response(),
                         404 => emqx_dashboard_swagger:error_codes(
                             [?NOT_FOUND], <<"Cluster link not found">>
                         ),
@@ -107,44 +115,30 @@ schema("/cluster/links/:name") ->
             }
     }.
 
+fields(link_config_response) ->
+    [
+        {node, hoconsc:mk(binary(), #{desc => ?DESC("node")})},
+        {status, hoconsc:mk(status(), #{desc => ?DESC("status")})}
+        | emqx_cluster_link_schema:fields("link")
+    ].
+
 %%--------------------------------------------------------------------
 %% API Handler funcs
 %%--------------------------------------------------------------------
 
 '/cluster/links'(get, _Params) ->
-    ?OK(get_raw());
+    handle_list();
 '/cluster/links'(post, #{body := Body = #{<<"name">> := Name}}) ->
     with_link(
         Name,
         return(?BAD_REQUEST('ALREADY_EXISTS', <<"Cluster link already exists">>)),
-        fun() ->
-            case emqx_cluster_link_config:create(Body) of
-                {ok, Res} ->
-                    ?CREATED(Res);
-                {error, Reason} ->
-                    Message = list_to_binary(io_lib:format("Create link failed ~p", [Reason])),
-                    ?BAD_REQUEST(Message)
-            end
-        end
+        fun() -> handle_create(Name, Body) end
     ).
 
 '/cluster/links/:name'(get, #{bindings := #{name := Name}}) ->
-    with_link(Name, fun(Link) -> ?OK(Link) end, not_found());
+    with_link(Name, fun(Link) -> handle_lookup(Name, Link) end, not_found());
 '/cluster/links/:name'(put, #{bindings := #{name := Name}, body := Params0}) ->
-    with_link(
-        Name,
-        fun(Link) ->
-            Params = Params0#{<<"name">> => Name},
-            case emqx_cluster_link_config:update_one_link(Params) of
-                {ok, Res} ->
-                    ?OK(Res);
-                {error, Reason} ->
-                    Message = list_to_binary(io_lib:format("Update link failed ~p", [Reason])),
-                    ?BAD_REQUEST(Message)
-            end
-        end,
-        not_found()
-    );
+    with_link(Name, fun() -> handle_update(Name, Params0) end, not_found());
 '/cluster/links/:name'(delete, #{bindings := #{name := Name}}) ->
     with_link(
         Name,
@@ -164,6 +158,48 @@ schema("/cluster/links/:name") ->
 %% Internal funcs
 %%--------------------------------------------------------------------
 
+handle_list() ->
+    Links = get_raw(),
+    NodeResults = get_all_link_status_cluster(),
+    NameToStatus = collect_all_status(NodeResults),
+    EmptyStatus = #{status => inconsistent, node_status => []},
+    Response =
+        lists:map(
+            fun(#{<<"name">> := Name} = Link) ->
+                Status = maps:get(Name, NameToStatus, EmptyStatus),
+                maps:merge(Link, Status)
+            end,
+            Links
+        ),
+    ?OK(Response).
+
+handle_create(Name, Params) ->
+    case emqx_cluster_link_config:create(Params) of
+        {ok, Link} ->
+            ?CREATED(add_status(Name, Link));
+        {error, Reason} ->
+            Message = list_to_binary(io_lib:format("Create link failed ~p", [Reason])),
+            ?BAD_REQUEST(Message)
+    end.
+
+handle_lookup(Name, Link) ->
+    ?OK(add_status(Name, Link)).
+
+add_status(Name, Link) ->
+    NodeResults = get_link_status_cluster(Name),
+    Status = collect_single_status(NodeResults),
+    maps:merge(Link, Status).
+
+handle_update(Name, Params0) ->
+    Params = Params0#{<<"name">> => Name},
+    case emqx_cluster_link_config:update_one_link(Params) of
+        {ok, Link} ->
+            ?OK(add_status(Name, Link));
+        {error, Reason} ->
+            Message = list_to_binary(io_lib:format("Update link failed ~p", [Reason])),
+            ?BAD_REQUEST(Message)
+    end.
+
 get_raw() ->
     #{<<"cluster">> := #{<<"links">> := Links}} =
         emqx_config:fill_defaults(
@@ -172,15 +208,130 @@ get_raw() ->
         ),
     Links.
 
-links_config_schema() ->
-    emqx_cluster_link_schema:links_schema(
-        #{
-            examples => #{<<"example">> => links_config_example()}
+get_all_link_status_cluster() ->
+    case emqx_cluster_link_mqtt:get_all_resources_cluster() of
+        {error, BadResults} ->
+            ?SLOG(warning, #{
+                msg => "cluster_link_api_all_status_bad_erpc_results",
+                results => BadResults
+            }),
+            [];
+        {ok, NodeResults} ->
+            NodeResults
+    end.
+
+get_link_status_cluster(Name) ->
+    case emqx_cluster_link_mqtt:get_resource_cluster(Name) of
+        {error, BadResults} ->
+            ?SLOG(warning, #{
+                msg => "cluster_link_api_lookup_status_bad_erpc_results",
+                results => BadResults
+            }),
+            [];
+        {ok, NodeResults} ->
+            NodeResults
+    end.
+
+-spec collect_all_status([{node(), #{cluster_name() => _}}]) ->
+    #{
+        cluster_name() => #{
+            node := node(),
+            status := emqx_resource:resource_status() | inconsistent
         }
+    }.
+collect_all_status(NodeResults) ->
+    Reindexed = lists:foldl(
+        fun({Node, AllLinkData}, Acc) ->
+            maps:fold(
+                fun(Name, Data, AccIn) ->
+                    collect_all_status1(Node, Name, Data, AccIn)
+                end,
+                Acc,
+                AllLinkData
+            )
+        end,
+        #{},
+        NodeResults
+    ),
+    maps:fold(
+        fun(Name, NodeToData, Acc) ->
+            OnlyStatus = [S || #{status := S} <- maps:values(NodeToData)],
+            SummaryStatus =
+                case lists:usort(OnlyStatus) of
+                    [SameStatus] -> SameStatus;
+                    _ -> inconsistent
+                end,
+            NodeStatus = lists:map(
+                fun({Node, #{status := S}}) ->
+                    #{node => Node, status => S}
+                end,
+                maps:to_list(NodeToData)
+            ),
+            Acc#{
+                Name => #{
+                    status => SummaryStatus,
+                    node_status => NodeStatus
+                }
+            }
+        end,
+        #{},
+        Reindexed
     ).
 
+collect_all_status1(Node, Name, Data, Acc) ->
+    maps:update_with(
+        Name,
+        fun(Old) -> Old#{Node => Data} end,
+        #{Node => Data},
+        Acc
+    ).
+
+collect_single_status(NodeResults) ->
+    NodeStatus =
+        lists:map(
+            fun
+                ({Node, {ok, #{status := S}}}) ->
+                    #{node => Node, status => S};
+                ({Node, {error, _}}) ->
+                    #{node => Node, status => ?status_disconnected};
+                ({Node, _}) ->
+                    #{node => Node, status => inconsistent}
+            end,
+            NodeResults
+        ),
+    OnlyStatus = [S || #{status := S} <- NodeStatus],
+    SummaryStatus =
+        case lists:usort(OnlyStatus) of
+            [SameStatus] -> SameStatus;
+            _ -> inconsistent
+        end,
+    #{
+        status => SummaryStatus,
+        node_status => NodeStatus
+    }.
+
+links_config_schema_response() ->
+    hoconsc:mk(hoconsc:array(hoconsc:ref(?MODULE, link_config_response)), #{
+        examples => #{<<"example">> => links_config_response_example()}
+    }).
+
 link_config_schema() ->
-    emqx_cluster_link_schema:link_schema().
+    hoconsc:mk(emqx_cluster_link_schema:link_schema(), #{
+        examples => #{<<"example">> => hd(links_config_example())}
+    }).
+
+link_config_schema_response() ->
+    hoconsc:mk(
+        hoconsc:ref(?MODULE, link_config_response),
+        #{
+            examples => #{
+                <<"example">> => hd(links_config_response_example())
+            }
+        }
+    ).
+
+status() ->
+    hoconsc:enum([?status_connected, ?status_disconnected, ?status_connecting, inconsistent]).
 
 param_path_name() ->
     {name,
@@ -197,6 +348,22 @@ param_path_name() ->
 update_link_config_schema() ->
     proplists:delete(name, emqx_cluster_link_schema:fields("link")).
 
+links_config_response_example() ->
+    lists:map(
+        fun(LinkEx) ->
+            LinkEx#{
+                <<"status">> => <<"connected">>,
+                <<"node_status">> => [
+                    #{
+                        <<"node">> => <<"emqx1@emqx.net">>,
+                        <<"status">> => <<"connected">>
+                    }
+                ]
+            }
+        end,
+        links_config_example()
+    ).
+
 links_config_example() ->
     [
         #{
@@ -229,7 +396,8 @@ with_link(Name, FoundFn, NotFoundFn) ->
     case emqx_cluster_link_config:link_raw(Name) of
         undefined ->
             NotFoundFn();
-        Link = #{} ->
+        Link0 = #{} ->
+            Link = fill_defaults_single(Link0),
             {arity, Arity} = erlang:fun_info(FoundFn, arity),
             case Arity of
                 1 -> FoundFn(Link);
@@ -237,6 +405,14 @@ with_link(Name, FoundFn, NotFoundFn) ->
             end
     end.
 
+fill_defaults_single(Link0) ->
+    #{<<"cluster">> := #{<<"links">> := [Link]}} =
+        emqx_config:fill_defaults(
+            #{<<"cluster">> => #{<<"links">> => [Link0]}},
+            #{obfuscate_sensitive_values => true}
+        ),
+    Link.
+
 return(Response) ->
     fun() -> Response end.
 

apps/emqx_cluster_link/src/emqx_cluster_link_mqtt.erl

@@ -46,6 +46,16 @@
     forward/2
 ]).
 
+-export([
+    get_all_resources_cluster/0,
+    get_resource_cluster/1
+]).
+%% BpAPI / RPC Targets
+-export([
+    get_resource_local_v1/1,
+    get_all_resources_local_v1/0
+]).
+
 -define(MSG_CLIENTID_SUFFIX, ":msg:").
 
 -define(MQTT_HOST_OPTS, #{default_port => 1883}).
@@ -80,6 +90,8 @@
 
 -define(PUB_TIMEOUT, 10_000).
 
+-type cluster_name() :: binary().
+
 -spec ensure_msg_fwd_resource(map()) ->
     {ok, emqx_resource:resource_data() | already_started} | {error, Reason :: term()}.
 ensure_msg_fwd_resource(#{name := Name, resource_opts := ResOpts} = ClusterConf) ->
@@ -89,10 +101,57 @@ ensure_msg_fwd_resource(#{name := Name, resource_opts := ResOpts} = ClusterConf)
     },
     emqx_resource:create_local(?MSG_RES_ID(Name), ?RES_GROUP, ?MODULE, ClusterConf, ResOpts1).
 
--spec remove_msg_fwd_resource(binary() | map()) -> ok | {error, Reason :: term()}.
+-spec remove_msg_fwd_resource(cluster_name()) -> ok | {error, Reason :: term()}.
 remove_msg_fwd_resource(ClusterName) ->
     emqx_resource:remove_local(?MSG_RES_ID(ClusterName)).
 
+-spec get_all_resources_cluster() ->
+    {ok, [{node(), #{cluster_name() => emqx_resource:resource_data()}}]}
+    | {error, [term()]}.
+get_all_resources_cluster() ->
+    Nodes = emqx:running_nodes(),
+    Results = emqx_cluster_link_proto_v1:get_all_resources(Nodes),
+    sequence_multicall_results(Nodes, Results).
+
+-spec get_resource_cluster(cluster_name()) ->
+    {ok, [{node(), {ok, emqx_resource:resource_data()} | {error, not_found}}]}
+    | {error, [term()]}.
+get_resource_cluster(ClusterName) ->
+    Nodes = emqx:running_nodes(),
+    Results = emqx_cluster_link_proto_v1:get_resource(Nodes, ClusterName),
+    sequence_multicall_results(Nodes, Results).
+
+%% RPC Target in `emqx_cluster_link_proto_v1'.
+-spec get_resource_local_v1(cluster_name()) ->
+    {ok, emqx_resource:resource_data()} | {error, not_found}.
+get_resource_local_v1(ClusterName) ->
+    case emqx_resource:get_instance(?MSG_RES_ID(ClusterName)) of
+        {ok, _ResourceGroup, ResourceData} ->
+            {ok, ResourceData};
+        {error, not_found} ->
+            {error, not_found}
+    end.
+
+%% RPC Target in `emqx_cluster_link_proto_v1'.
+-spec get_all_resources_local_v1() -> #{cluster_name() => emqx_resource:resource_data()}.
+get_all_resources_local_v1() ->
+    lists:foldl(
+        fun
+            (?MSG_RES_ID(Name) = Id, Acc) ->
+                case emqx_resource:get_instance(Id) of
+                    {ok, ?RES_GROUP, ResourceData} ->
+                        Acc#{Name => ResourceData};
+                    _ ->
+                        Acc
+                end;
+            (_Id, Acc) ->
+                %% Doesn't follow the naming pattern; manually crafted?
+                Acc
+        end,
+        #{},
+        emqx_resource:list_group_instances(?RES_GROUP)
+    ).
+
 %%--------------------------------------------------------------------
 %% emqx_resource callbacks (message forwarding)
 %%--------------------------------------------------------------------
@@ -419,3 +478,16 @@ emqtt_client_opts(ClientIdSuffix, ClusterConf) ->
     #{clientid := BaseClientId} = Opts = emqx_cluster_link_config:mk_emqtt_options(ClusterConf),
     ClientId = emqx_bridge_mqtt_lib:clientid_base([BaseClientId, ClientIdSuffix]),
     Opts#{clientid => ClientId}.
+
+-spec sequence_multicall_results([node()], emqx_rpc:erpc_multicall(term())) ->
+    {ok, [{node(), term()}]} | {error, [term()]}.
+sequence_multicall_results(Nodes, Results) ->
+    case lists:partition(fun is_ok/1, lists:zip(Nodes, Results)) of
+        {OkResults, []} ->
+            {ok, [{Node, Res} || {Node, {ok, Res}} <- OkResults]};
+        {_OkResults, BadResults} ->
+            {error, BadResults}
+    end.
+
+is_ok({_Node, {ok, _}}) -> true;
+is_ok(_) -> false.

apps/emqx_cluster_link/src/proto/emqx_cluster_link_proto_v1.erl

@@ -0,0 +1,31 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2024 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%--------------------------------------------------------------------
+
+-module(emqx_cluster_link_proto_v1).
+
+-behaviour(emqx_bpapi).
+
+-export([
+    introduced_in/0,
+
+    get_resource/2,
+    get_all_resources/1
+]).
+
+-include_lib("emqx/include/bpapi.hrl").
+
+-define(TIMEOUT, 15000).
+
+introduced_in() ->
+    "5.7.2".
+
+-spec get_resource([node()], binary()) ->
+    emqx_rpc:erpc_multicall({ok, emqx_resource:resource_data()} | {error, not_found}).
+get_resource(Nodes, ClusterName) ->
+    erpc:multicall(Nodes, emqx_cluster_link_mqtt, get_resource_local_v1, [ClusterName], ?TIMEOUT).
+
+-spec get_all_resources([node()]) ->
+    emqx_rpc:erpc_multicall(#{binary() => emqx_resource:resource_data()}).
+get_all_resources(Nodes) ->
+    erpc:multicall(Nodes, emqx_cluster_link_mqtt, get_all_resources_local_v1, [], ?TIMEOUT).

apps/emqx_cluster_link/test/emqx_cluster_link_api_SUITE.erl

@@ -37,6 +37,8 @@
     "-----END CERTIFICATE-----"
 >>).
 
+-define(ON(NODE, BODY), erpc:call(NODE, fun() -> BODY end)).
+
 %%------------------------------------------------------------------------------
 %% CT boilerplate
 %%------------------------------------------------------------------------------
@@ -67,10 +69,36 @@ end_per_suite(Config) ->
 auth_header() ->
     emqx_mgmt_api_test_util:auth_header_().
 
+init_per_testcase(t_status = TestCase, Config) ->
+    ok = emqx_cth_suite:stop_apps([emqx_dashboard]),
+    SourceClusterSpec = emqx_cluster_link_SUITE:mk_source_cluster(TestCase, Config),
+    TargetClusterSpec = emqx_cluster_link_SUITE:mk_target_cluster(TestCase, Config),
+    SourceNodes = [SN1 | _] = emqx_cth_cluster:start(SourceClusterSpec),
+    TargetNodes = emqx_cth_cluster:start(TargetClusterSpec),
+    emqx_cluster_link_SUITE:start_cluster_link(SourceNodes ++ TargetNodes, Config),
+    erpc:call(SN1, emqx_cth_suite, start_apps, [
+        [emqx_management, emqx_mgmt_api_test_util:emqx_dashboard()],
+        #{work_dir => emqx_cth_suite:work_dir(TestCase, Config)}
+    ]),
+    [
+        {source_nodes, SourceNodes},
+        {target_nodes, TargetNodes}
+        | Config
+    ];
 init_per_testcase(_TC, Config) ->
     {ok, _} = emqx_cluster_link_config:update([]),
     Config.
 
+end_per_testcase(t_status, Config) ->
+    SourceNodes = ?config(source_nodes, Config),
+    TargetNodes = ?config(target_nodes, Config),
+    ok = emqx_cth_cluster:stop(SourceNodes),
+    ok = emqx_cth_cluster:stop(TargetNodes),
+    _ = emqx_cth_suite:start_apps(
+        [emqx_mgmt_api_test_util:emqx_dashboard()],
+        #{work_dir => emqx_cth_suite:work_dir(Config)}
+    ),
+    ok;
 end_per_testcase(_TC, _Config) ->
     ok.
 
@@ -158,6 +186,8 @@ t_put_invalid(_Config) ->
         update_link(Name, maps:remove(<<"server">>, link_params()))
     ).
 
+%% Tests a sequence of CRUD operations and their expected responses, for common use cases
+%% and configuration states.
 t_crud(_Config) ->
     %% No links initially.
     ?assertMatch({200, []}, list()),
@@ -167,13 +197,43 @@ t_crud(_Config) ->
     ?assertMatch({404, _}, update_link(NameA, link_params())),
 
     Params1 = link_params(),
-    ?assertMatch({201, #{<<"name">> := NameA}}, create_link(NameA, Params1)),
+    ?assertMatch(
+        {201, #{
+            <<"name">> := NameA,
+            <<"status">> := _,
+            <<"node_status">> := [#{<<"node">> := _, <<"status">> := _} | _]
+        }},
+        create_link(NameA, Params1)
+    ),
     ?assertMatch({400, #{<<"code">> := <<"ALREADY_EXISTS">>}}, create_link(NameA, Params1)),
-    ?assertMatch({200, [#{<<"name">> := NameA}]}, list()),
-    ?assertMatch({200, #{<<"name">> := NameA}}, get_link(NameA)),
+    ?assertMatch(
+        {200, [
+            #{
+                <<"name">> := NameA,
+                <<"status">> := _,
+                <<"node_status">> := [#{<<"node">> := _, <<"status">> := _} | _]
+            }
+        ]},
+        list()
+    ),
+    ?assertMatch(
+        {200, #{
+            <<"name">> := NameA,
+            <<"status">> := _,
+            <<"node_status">> := [#{<<"node">> := _, <<"status">> := _} | _]
+        }},
+        get_link(NameA)
+    ),
 
     Params2 = Params1#{<<"pool_size">> := 2},
-    ?assertMatch({200, #{<<"name">> := NameA}}, update_link(NameA, Params2)),
+    ?assertMatch(
+        {200, #{
+            <<"name">> := NameA,
+            <<"status">> := _,
+            <<"node_status">> := [#{<<"node">> := _, <<"status">> := _} | _]
+        }},
+        update_link(NameA, Params2)
+    ),
 
     ?assertMatch({204, _}, delete_link(NameA)),
     ?assertMatch({404, _}, delete_link(NameA)),
@@ -182,3 +242,147 @@ t_crud(_Config) ->
     ?assertMatch({200, []}, list()),
 
     ok.
+
+%% Verifies the behavior of reported status under different conditions when listing all
+%% links and when fetching a specific link.
+t_status(Config) ->
+    [SN1 | _] = ?config(source_nodes, Config),
+    Name = <<"cl.target">>,
+    ?assertMatch(
+        {200, [
+            #{
+                <<"status">> := <<"connected">>,
+                <<"node_status">> := [
+                    #{
+                        <<"node">> := _,
+                        <<"status">> := <<"connected">>
+                    },
+                    #{
+                        <<"node">> := _,
+                        <<"status">> := <<"connected">>
+                    }
+                ]
+            }
+        ]},
+        list()
+    ),
+    ?assertMatch(
+        {200, #{
+            <<"status">> := <<"connected">>,
+            <<"node_status">> := [
+                #{
+                    <<"node">> := _,
+                    <<"status">> := <<"connected">>
+                },
+                #{
+                    <<"node">> := _,
+                    <<"status">> := <<"connected">>
+                }
+            ]
+        }},
+        get_link(Name)
+    ),
+
+    %% If one of the nodes reports a different status, the cluster is inconsistent.
+    ProtoMod = emqx_cluster_link_proto_v1,
+    ?ON(SN1, begin
+        ok = meck:new(ProtoMod, [no_link, passthrough, no_history]),
+        meck:expect(ProtoMod, get_all_resources, fun(Nodes) ->
+            [Res1, {ok, Res2A} | Rest] = meck:passthrough([Nodes]),
+            %% Res2A :: #{cluster_name() => emqx_resource:resource_data()}
+            Res2B = maps:map(fun(_, Data) -> Data#{status := disconnected} end, Res2A),
+            [Res1, {ok, Res2B} | Rest]
+        end),
+        meck:expect(ProtoMod, get_resource, fun(Nodes, LinkName) ->
+            [Res1, {ok, {ok, Res2A}} | Rest] = meck:passthrough([Nodes, LinkName]),
+            Res2B = Res2A#{status := disconnected},
+            [Res1, {ok, {ok, Res2B}} | Rest]
+        end)
+    end),
+    ?assertMatch(
+        {200, [
+            #{
+                <<"status">> := <<"inconsistent">>,
+                <<"node_status">> := [
+                    #{
+                        <<"node">> := _,
+                        <<"status">> := <<"connected">>
+                    },
+                    #{
+                        <<"node">> := _,
+                        <<"status">> := <<"disconnected">>
+                    }
+                ]
+            }
+        ]},
+        list()
+    ),
+    ?assertMatch(
+        {200, #{
+            <<"status">> := <<"inconsistent">>,
+            <<"node_status">> := [
+                #{
+                    <<"node">> := _,
+                    <<"status">> := <<"connected">>
+                },
+                #{
+                    <<"node">> := _,
+                    <<"status">> := <<"disconnected">>
+                }
+            ]
+        }},
+        get_link(Name)
+    ),
+
+    %% Simulating erpc failures
+    ?ON(SN1, begin
+        meck:expect(ProtoMod, get_all_resources, fun(Nodes) ->
+            [Res1, _ | Rest] = meck:passthrough([Nodes]),
+            [Res1, {error, {erpc, noconnection}} | Rest]
+        end),
+        meck:expect(ProtoMod, get_resource, fun(Nodes, LinkName) ->
+            [Res1, _ | Rest] = meck:passthrough([Nodes, LinkName]),
+            [Res1, {error, {erpc, noconnection}} | Rest]
+        end)
+    end),
+    ?assertMatch(
+        {200, [
+            #{
+                <<"status">> := <<"inconsistent">>,
+                <<"node_status">> := []
+            }
+        ]},
+        list()
+    ),
+    ?assertMatch(
+        {200, #{
+            <<"status">> := <<"inconsistent">>,
+            <<"node_status">> := []
+        }},
+        get_link(Name)
+    ),
+    %% Simulate another inconsistency
+    ?ON(SN1, begin
+        meck:expect(ProtoMod, get_resource, fun(Nodes, LinkName) ->
+            [Res1, _ | Rest] = meck:passthrough([Nodes, LinkName]),
+            [Res1, {ok, {error, not_found}} | Rest]
+        end)
+    end),
+    ?assertMatch(
+        {200, #{
+            <<"status">> := <<"inconsistent">>,
+            <<"node_status">> := [
+                #{
+                    <<"node">> := _,
+                    <<"status">> := <<"connected">>
+                },
+                #{
+                    <<"node">> := _,
+                    <<"status">> := <<"disconnected">>
+                }
+            ]
+        }},
+        get_link(Name)
+    ),
+
+    ok.