Nack rejected messages to MQTT 5.0 client

ansd · ansd · commit 2a4301e12d58 · 2023-08-09T15:31:14.000+02:00
since MQTT 5.0 supports negative acknowledgements thanks to reason codes
in the PUBACK packet.

We could either choose reason code 128 or 131. The description code for
131 applies for rejected messages, hence this commit uses 131:
&gt; The PUBLISH is valid but the receiver is not willing to accept it.
diff --git a/deps/rabbit/src/rabbit_confirms.erl b/deps/rabbit/src/rabbit_confirms.erl
@@ -144,9 +144,3 @@ next_smallest(S, U) when is_map_key(S, U) ->
 next_smallest(S, U) ->
     %% TODO: this is potentially infinitely recursive if called incorrectly
     next_smallest(S+1, U).
-
-
-
--ifdef(TEST).
--include_lib("eunit/include/eunit.hrl").
--endif.
diff --git a/deps/rabbit/test/rabbit_confirms_SUITE.erl b/deps/rabbit/test/rabbit_confirms_SUITE.erl
@@ -1,11 +1,6 @@
 -module(rabbit_confirms_SUITE).
 
--compile(export_all).
-
--export([
-         ]).
-
--include_lib("common_test/include/ct.hrl").
+-compile([export_all, nowarn_export_all]).
 -include_lib("eunit/include/eunit.hrl").
 
 %%%===================================================================
@@ -17,40 +12,13 @@ all() ->
      {group, tests}
     ].
 
-
-all_tests() ->
-    [
-     confirm,
-     reject,
-     remove_queue
-    ].
-
 groups() ->
     [
-     {tests, [], all_tests()}
-    ].
-
-init_per_suite(Config) ->
-    Config.
-
-end_per_suite(_Config) ->
-    ok.
-
-init_per_group(_Group, Config) ->
-    Config.
-
-end_per_group(_Group, _Config) ->
-    ok.
-
-init_per_testcase(_TestCase, Config) ->
-    Config.
-
-end_per_testcase(_TestCase, _Config) ->
-    ok.
-
-%%%===================================================================
-%%% Test cases
-%%%===================================================================
+     {tests, [shuffle],
+      [confirm,
+       reject,
+       remove_queue
+      ]}].
 
 confirm(_Config) ->
     XName = rabbit_misc:r(<<"/">>, exchange, <<"X">>),
@@ -93,7 +61,6 @@ confirm(_Config) ->
     ?assertEqual(0, rabbit_confirms:size(U7)),
     ?assertEqual(undefined, rabbit_confirms:smallest(U7)),
 
-
     U8 = rabbit_confirms:insert(2, [QName], XName, U1),
     {[{1, XName}, {2, XName}], _U9} = rabbit_confirms:confirm([1, 2], QName, U8),
     ok.
@@ -126,7 +93,6 @@ reject(_Config) ->
     {error, not_found} = rabbit_confirms:reject(2, U5),
     ?assertEqual(1, rabbit_confirms:size(U5)),
     ?assertEqual(1, rabbit_confirms:smallest(U5)),
-
     ok.
 
 remove_queue(_Config) ->
@@ -147,8 +113,4 @@ remove_queue(_Config) ->
     U5 = rabbit_confirms:insert(1, [QName], XName, U0),
     U6 = rabbit_confirms:insert(2, [QName], XName, U5),
     {[{1, XName}, {2, XName}], _U} = rabbit_confirms:remove_queue(QName, U6),
-
     ok.
-
-
-%% Utility
diff --git a/deps/rabbitmq_mqtt/BUILD.bazel b/deps/rabbitmq_mqtt/BUILD.bazel
@@ -281,6 +281,14 @@ rabbitmq_suite(
     ],
 )
 
+rabbitmq_suite(
+    name = "rabbit_mqtt_confirms_SUITE",
+    size = "small",
+    deps = [
+        "//deps/rabbit_common:erlang_app",
+    ],
+)
+
 assert_suites()
 
 alias(
diff --git a/deps/rabbitmq_mqtt/app.bzl b/deps/rabbitmq_mqtt/app.bzl
@@ -331,3 +331,11 @@ def test_suite_beam_files(name = "test_suite_beam_files"):
         erlc_opts = "//:test_erlc_opts",
         deps = ["//deps/amqp_client:erlang_app"],
     )
+    erlang_bytecode(
+        name = "rabbit_mqtt_confirms_SUITE_beam_files",
+        testonly = True,
+        srcs = ["test/rabbit_mqtt_confirms_SUITE.erl"],
+        outs = ["test/rabbit_mqtt_confirms_SUITE.beam"],
+        app_name = "rabbitmq_mqtt",
+        erlc_opts = "//:test_erlc_opts",
+    )
diff --git a/deps/rabbitmq_mqtt/src/rabbit_mqtt_confirms.erl b/deps/rabbitmq_mqtt/src/rabbit_mqtt_confirms.erl
@@ -49,22 +49,21 @@ insert(PktId, QNames, State)
 -spec confirm([packet_id()], queue_name(), state()) ->
     {[packet_id()], state()}.
 confirm(PktIds, QName, State0) ->
-    {L0, State} = lists:foldl(fun(PktId, Acc) ->
-                                      confirm_one(PktId, QName, Acc)
-                              end, {[], State0}, PktIds),
-    L = lists:reverse(L0),
-    {L, State}.
+    lists:foldl(fun(PktId, Acc) ->
+                        confirm_one(PktId, QName, Acc)
+                end, {[], State0}, PktIds).
 
--spec reject(packet_id(), state()) ->
-    {ok, state()} | {error, not_found}.
-reject(PktId, State0)
-  when is_integer(PktId) ->
-    case maps:take(PktId, State0) of
-        {_, State} ->
-            {ok, State};
-        error ->
-            {error, not_found}
-    end.
+-spec reject([packet_id()], state()) ->
+    {[packet_id()], state()}.
+reject(PktIds, State0) ->
+    lists:foldl(fun(PktId, Acc = {Rejs, S0}) ->
+                        case maps:take(PktId, S0) of
+                            {_, S} ->
+                                {[PktId | Rejs], S};
+                            error ->
+                                Acc
+                        end
+                end, {[], State0}, PktIds).
 
 %% idempotent
 -spec remove_queue(queue_name(), state()) ->
@@ -77,7 +76,7 @@ remove_queue(QName, State) ->
                   (_, _, PktIds) ->
                        PktIds
                end, [], State),
-    confirm(lists:sort(PktIds), QName, State).
+    confirm(PktIds, QName, State).
 
 %% INTERNAL
 
diff --git a/deps/rabbitmq_mqtt/src/rabbit_mqtt_processor.erl b/deps/rabbitmq_mqtt/src/rabbit_mqtt_processor.erl
@@ -1686,17 +1686,15 @@ process_routing_confirm(#delivery{confirm = true,
     U = rabbit_mqtt_confirms:insert(PktId, QNames, U0),
     State#state{unacked_client_pubs = U}.
 
--spec send_puback(list(packet_id()), state()) -> ok.
-send_puback(PktIds0, State)
+-spec send_puback(packet_id() | list(packet_id()), reason_code(), state()) -> ok.
+send_puback(PktIds0, ReasonCode, State)
   when is_list(PktIds0) ->
     %% Classic queues confirm messages unordered.
     %% Let's sort them here assuming most MQTT clients send with an increasing packet identifier.
     PktIds = lists:usort(PktIds0),
     lists:foreach(fun(Id) ->
-                          send_puback(Id, ?RC_SUCCESS, State)
-                  end, PktIds).
-
--spec send_puback(packet_id(), reason_code(), state()) -> ok.
+                          send_puback(Id, ReasonCode, State)
+                  end, PktIds);
 send_puback(PktId, ReasonCode, State = #state{cfg = #cfg{proto_ver = ProtoVer}}) ->
     rabbit_global_counters:messages_confirmed(ProtoVer, 1),
     Packet = #mqtt_packet{fixed = #mqtt_packet_fixed{type = ?PUBACK},
@@ -1971,7 +1969,7 @@ handle_down({{'DOWN', QName}, _MRef, process, QPid, Reason},
             QStates = rabbit_queue_type:remove(QRef, QStates1),
             State = State0#state{queue_states = QStates,
                                  unacked_client_pubs = U},
-            send_puback(ConfirmPktIds, State),
+            send_puback(ConfirmPktIds, ?RC_SUCCESS, State),
             {ok, State}
     end.
 
@@ -2001,7 +1999,7 @@ handle_queue_event({queue_event, QName, Evt},
             QStates = rabbit_queue_type:remove(QName, QStates0),
             State = State1#state{queue_states = QStates,
                                  unacked_client_pubs = U},
-            send_puback(ConfirmPktIds, State),
+            send_puback(ConfirmPktIds, ?RC_SUCCESS, State),
             {ok, State};
         {protocol_error, _Type, _Reason, _ReasonArgs} = Error ->
             {error, Error, State0}
@@ -2013,19 +2011,21 @@ handle_queue_actions(Actions, #state{} = State0) ->
               deliver_to_client(Msgs, Ack, S);
           ({settled, QName, PktIds}, S = #state{unacked_client_pubs = U0}) ->
               {ConfirmPktIds, U} = rabbit_mqtt_confirms:confirm(PktIds, QName, U0),
-              send_puback(ConfirmPktIds, S),
-              S#state{unacked_client_pubs = U};
-          ({rejected, _QName, PktIds}, S = #state{unacked_client_pubs = U0}) ->
-              %% Negative acks are supported in MQTT v5 only.
-              %% Therefore, in MQTT v3 and v4 we ignore rejected messages.
-              U = lists:foldl(
-                    fun(PktId, Acc0) ->
-                            case rabbit_mqtt_confirms:reject(PktId, Acc0) of
-                                {ok, Acc} -> Acc;
-                                {error, not_found} -> Acc0
-                            end
-                    end, U0, PktIds),
+              send_puback(ConfirmPktIds, ?RC_SUCCESS, S),
               S#state{unacked_client_pubs = U};
+          ({rejected, _QName, PktIds}, S0 = #state{unacked_client_pubs = U0,
+                                                   cfg = #cfg{proto_ver = ProtoVer}}) ->
+              {RejectPktIds, U} = rabbit_mqtt_confirms:reject(PktIds, U0),
+              S = S0#state{unacked_client_pubs = U},
+              %% Negative acks are supported only in MQTT v5. In MQTT v3 and v4 we ignore
+              %% rejected messages since we can only (but must not) send a positive ack.
+              case ProtoVer of
+                  ?MQTT_PROTO_V5 ->
+                      send_puback(RejectPktIds, ?RC_IMPLEMENTATION_SPECIFIC_ERROR, S);
+                  _ ->
+                      ok
+              end,
+              S;
           ({block, QName}, S = #state{queues_soft_limit_exceeded = QSLE}) ->
               S#state{queues_soft_limit_exceeded = sets:add_element(QName, QSLE)};
           ({unblock, QName}, S = #state{queues_soft_limit_exceeded = QSLE}) ->
diff --git a/deps/rabbitmq_mqtt/test/rabbit_mqtt_confirms_SUITE.erl b/deps/rabbitmq_mqtt/test/rabbit_mqtt_confirms_SUITE.erl
@@ -0,0 +1,109 @@
+-module(rabbit_mqtt_confirms_SUITE).
+
+-compile([export_all, nowarn_export_all]).
+-include_lib("eunit/include/eunit.hrl").
+
+%%%===================================================================
+%%% Common Test callbacks
+%%%===================================================================
+
+all() ->
+    [
+     {group, tests}
+    ].
+
+groups() ->
+    [
+     {tests, [shuffle],
+      [confirm,
+       reject,
+       remove_queue
+      ]}].
+
+-define(MOD, rabbit_mqtt_confirms).
+
+confirm(_Config) ->
+    QName = rabbit_misc:r(<<"/">>, queue, <<"Q">>),
+    QName2 = rabbit_misc:r(<<"/">>, queue, <<"Q2">>),
+    U0 = ?MOD:init(),
+    ?assertEqual(0, ?MOD:size(U0)),
+
+    U1 = ?MOD:insert(1, [QName], U0),
+    ?assertEqual(1, ?MOD:size(U1)),
+    ?assert(?MOD:contains(1, U1)),
+
+    {[1], U2} = ?MOD:confirm([1], QName, U1),
+    ?assertEqual(0, ?MOD:size(U2)),
+    ?assertNot(?MOD:contains(1, U2)),
+
+    U3 = ?MOD:insert(2, [QName], U1),
+    ?assertEqual(2, ?MOD:size(U3)),
+    ?assert(?MOD:contains(1, U3)),
+    ?assert(?MOD:contains(2, U3)),
+
+    {[1], U4} = ?MOD:confirm([1], QName, U3),
+    ?assertEqual(1, ?MOD:size(U4)),
+    ?assertNot(?MOD:contains(1, U4)),
+    ?assert(?MOD:contains(2, U4)),
+
+    U5 = ?MOD:insert(2, [QName, QName2], U1),
+    ?assertEqual(2, ?MOD:size(U5)),
+    ?assert(?MOD:contains(1, U5)),
+    ?assert(?MOD:contains(2, U5)),
+
+    {[1], U6} = ?MOD:confirm([1, 2], QName, U5),
+    {[2], U7} = ?MOD:confirm([2], QName2, U6),
+    ?assertEqual(0, ?MOD:size(U7)),
+
+    U8 = ?MOD:insert(2, [QName], U1),
+    {Confirmed, _U9} = ?MOD:confirm([1, 2], QName, U8),
+    ?assertEqual([1, 2], lists:sort(Confirmed)),
+    ok.
+
+
+reject(_Config) ->
+    QName = rabbit_misc:r(<<"/">>, queue, <<"Q">>),
+    QName2 = rabbit_misc:r(<<"/">>, queue, <<"Q2">>),
+    U0 = ?MOD:init(),
+    ?assertEqual(0, ?MOD:size(U0)),
+
+    U1 = ?MOD:insert(1, [QName], U0),
+    ?assert(?MOD:contains(1, U1)),
+
+    {[1], U2} = ?MOD:reject([1], U1),
+    {[], U2} = ?MOD:reject([1], U2),
+    ?assertEqual(0, ?MOD:size(U2)),
+    ?assertNot(?MOD:contains(1, U2)),
+
+    U3 = ?MOD:insert(2, [QName, QName2], U1),
+
+    {[1], U4} = ?MOD:reject([1], U3),
+    {[], U4} = ?MOD:reject([1], U4),
+    ?assertEqual(1, ?MOD:size(U4)),
+
+    {[2], U5} = ?MOD:reject([2], U3),
+    {[], U5} = ?MOD:reject([2], U5),
+    ?assertEqual(1, ?MOD:size(U5)),
+    ?assert(?MOD:contains(1, U5)),
+    ok.
+
+remove_queue(_Config) ->
+    QName = rabbit_misc:r(<<"/">>, queue, <<"Q">>),
+    QName2 = rabbit_misc:r(<<"/">>, queue, <<"Q2">>),
+    U0 = ?MOD:init(),
+
+    U1 = ?MOD:insert(1, [QName, QName2], U0),
+    U2 = ?MOD:insert(2, [QName2], U1),
+    {[2], U3} = ?MOD:remove_queue(QName2, U2),
+    ?assertEqual(1, ?MOD:size(U3)),
+    ?assert(?MOD:contains(1, U3)),
+    {[1], U4} = ?MOD:remove_queue(QName, U3),
+    ?assertEqual(0, ?MOD:size(U4)),
+    ?assertNot(?MOD:contains(1, U4)),
+
+    U5 = ?MOD:insert(1, [QName], U0),
+    U6 = ?MOD:insert(2, [QName], U5),
+    {Confirmed, U7} = ?MOD:remove_queue(QName, U6),
+    ?assertEqual([1, 2], lists:sort(Confirmed)),
+    ?assertEqual(0, ?MOD:size(U7)),
+    ok.
diff --git a/deps/rabbitmq_mqtt/test/shared_SUITE.erl b/deps/rabbitmq_mqtt/test/shared_SUITE.erl
