Local shovels: generate multiple ack/nack as the channel does

Avoids overflowing source queue with individual ack/nacks

(cherry picked from commit 8a11650)

Author: dcorbacho

deps/rabbitmq_shovel/src/rabbit_local_shovel.erl

@@ -128,11 +128,19 @@ connect_dest(State = #{dest := Dest = #{resource_decl := {M, F, MFArgs},
               State#{dest => Dest#{current => #{queue_states => QState,
                                                 delivery_id => 1,
                                                 vhost => VHost},
-                                   unacked => #{}}};
+                                   unconfirmed => rabbit_confirms:init(),
+                                   rejected => [],
+                                   rejected_count => 0,
+                                   confirmed => [],
+                                   confirmed_count => 0}};
           _ ->
               State#{dest => Dest#{current => #{queue_states => QState,
                                                 vhost => VHost},
-                                   unacked => #{}}}
+                                   unconfirmed => rabbit_confirms:init(),
+                                   confirmed => [],
+                                   confirmed_count => 0,
+                                   rejected => [],
+                                   rejected_count => 0}}
       end).
 
 maybe_add_dest_queue(State = #{dest := Dest = #{queue := QName,
@@ -206,6 +214,7 @@ init_source(State = #{source := #{queue_r := QName,
 init_dest(#{name := Name,
             shovel_type := Type,
             dest := #{add_forward_headers := AFH} = Dst} = State) ->
+    _TRef = erlang:send_after(1000, self(), send_confirms_and_nacks),
     case AFH of
         true ->
             Props = #{<<"x-opt-shovelled-by">> => rabbit_nodes:cluster_name(),
@@ -291,6 +300,9 @@ handle_source({queue_event, #resource{name = Queue,
         {protocol_error, _Type, Reason, ReasonArgs} ->
             {stop, list_to_binary(io_lib:format(Reason, ReasonArgs))}
     end;
+handle_source(send_confirms_and_nacks, State) ->
+    _TRef = erlang:send_after(1000, self(), send_confirms_and_nacks),
+    send_confirms_and_nacks(State);
 handle_source({{'DOWN', #resource{name = Queue,
                                   kind = queue,
                                   virtual_host = VHost}}, _, _, _, _}  ,
@@ -305,9 +317,9 @@ handle_dest({queue_event, QRef, Evt},
     case rabbit_queue_type:handle_event(QRef, Evt, QueueStates0) of
         {ok, QState1, Actions} ->
             State = State0#{dest => Dest#{current => Current#{queue_states => QState1}}},
-            handle_dest_queue_actions(Actions, State);
+            send_confirms_and_nacks(handle_dest_queue_actions(Actions, State));
         {eol, Actions} ->
-            _ = handle_dest_queue_actions(Actions, State0),
+            _ = send_confirms_and_nacks(handle_dest_queue_actions(Actions, State0)),
             {stop, {outbound_link_or_channel_closure, queue_deleted}};
         {protocol_error, _Type, Reason, ReasonArgs} ->
             {stop, list_to_binary(io_lib:format(Reason, ReasonArgs))}
@@ -337,8 +349,7 @@ ack(DeliveryTag, Multiple, State) ->
 nack(DeliveryTag, Multiple, State) ->
     maybe_grant_credit(settle(requeue, DeliveryTag, Multiple, State)).
 
-forward(Tag, Msg0, #{dest := #{current := #{queue_states := QState} = Current,
-                               unacked := Unacked} = Dest,
+forward(Tag, Msg0, #{dest := #{current := #{queue_states := QState} = Current} = Dest,
                      ack_mode := AckMode} = State0) ->
     {Options, #{dest := #{current := Current1} = Dest1} = State} =
         case AckMode of
@@ -355,23 +366,21 @@ forward(Tag, Msg0, #{dest := #{current := #{queue_states := QState} = Current,
     case rabbit_queue_type:deliver(Queues, Msg, Options, QState) of
         {ok, QState1, Actions} ->
             State1 = State#{dest => Dest1#{current => Current1#{queue_states => QState1}}},
-            #{dest := Dst1} = State2 = rabbit_shovel_behaviour:incr_forwarded(State1),
-            State4 = rabbit_shovel_behaviour:decr_remaining_unacked(
+            State2 = rabbit_shovel_behaviour:incr_forwarded(State1),
+            State3 = rabbit_shovel_behaviour:decr_remaining_unacked(
                        case AckMode of
-                           no_ack ->
-                               rabbit_shovel_behaviour:decr_remaining(1, State2);
                            on_confirm when length(Queues) > 0 ->
-                               Correlation = maps:get(correlation, Options),
-                               State2#{dest => Dst1#{unacked => Unacked#{Correlation => Tag}}};
-                           on_confirm ->
-                               %% Drop the messages as 0.9.1, no destination available
-                               State3 = rabbit_shovel_behaviour:ack(Tag, false, State2),
-                               rabbit_shovel_behaviour:decr_remaining(1, State3);
+                               State2;
                            on_publish ->
-                               State3 = rabbit_shovel_behaviour:ack(Tag, false, State2),
-                               rabbit_shovel_behaviour:decr_remaining(1, State3)
+                               rabbit_shovel_behaviour:decr_remaining(
+                                 1,
+                                 record_confirms([{Tag, none}], State2));
+                           _ ->
+                               rabbit_shovel_behaviour:decr_remaining(1, State2)
                        end),
-            handle_dest_queue_actions(Actions, State4);
+            MsgSeqNo = maps:get(correlation, Options, undefined),
+            State4 = process_routing_confirm(MsgSeqNo, QNames, State3),
+            send_confirms_and_nacks(handle_dest_queue_actions(Actions, State4));
         {error, Reason} ->
             exit({shutdown, Reason})
     end.
@@ -455,14 +464,21 @@ increase_next_tag(#{source := Source = #{current := Current = #{next_tag := Deli
 
 handle_dest_queue_actions(Actions, State) ->
     lists:foldl(
-      fun({settled, _QName, MsgSeqNos}, S0) ->
-              confirm_to_inbound(fun(Tag, StateX) ->
-                                         rabbit_shovel_behaviour:ack(Tag, false, StateX)
-                                 end, MsgSeqNos, S0);
-         ({rejected, _QName, MsgSeqNos}, S0) ->
-              confirm_to_inbound(fun(Tag, StateX) ->
-                                         rabbit_shovel_behaviour:nack(Tag, false, StateX)
-                                 end, MsgSeqNos, S0);
+      fun({settled, QName, MsgSeqNos}, S0) ->
+              confirm(MsgSeqNos, QName, S0);
+         ({rejected, _QName, MsgSeqNos}, #{dest := Dst = #{unconfirmed := U0}} = S0) ->
+              {U, Rej} =
+              lists:foldr(
+                fun(SeqNo, {U1, Acc}) ->
+                        case rabbit_confirms:reject(SeqNo, U1) of
+                            {ok, MX, U2} ->
+                                {U2, [MX | Acc]};
+                            {error, not_found} ->
+                                {U1, Acc}
+                        end
+                end, {U0, []}, MsgSeqNos),
+              S = S0#{dest => Dst#{unconfirmed => U}},
+              record_rejects(Rej, S);
          %% TODO handle {block, QName}
          (_Action, S0) ->
               S0
@@ -647,23 +663,6 @@ route(Msg, #{current := #{vhost := VHost}}) ->
     Exchange = rabbit_exchange:lookup_or_die(ExchangeName),
     rabbit_exchange:route(Exchange, Msg, #{return_binding_keys => true}).
 
-confirm_to_inbound(ConfirmFun, SeqNos, State)
-  when is_list(SeqNos) ->
-    lists:foldl(fun(Seq, State0) ->
-                        confirm_to_inbound(ConfirmFun, Seq, State0)
-                end, State, SeqNos);
-confirm_to_inbound(ConfirmFun, Seq,
-                   State0 = #{dest := #{unacked := Unacked} = Dst}) ->
-    case Unacked of
-        #{Seq := InTag} ->
-            Unacked1 = maps:remove(Seq, Unacked),
-            State = rabbit_shovel_behaviour:decr_remaining(
-                      1, State0#{dest => Dst#{unacked => Unacked1}}),
-            ConfirmFun(InTag, State);
-        _ ->
-            State0
-    end.
-
 sent_delivery(#{source := #{delivery_count := DeliveryCount0,
                             credit := Credit0} = Src
                } = State0, NumMsgs) ->
@@ -736,3 +735,90 @@ handle_credit_reply({credit_reply, CTag, DeliveryCount, Credit, _Available, _Dra
             State0#{source => Src#{credit => Credit,
                                    at_least_one_credit_req_in_flight => false}}
     end.
+
+process_routing_confirm(undefined, _, State) ->
+    State;
+process_routing_confirm(MsgSeqNo, [], State)
+  when is_integer(MsgSeqNo) ->
+    record_confirms([{MsgSeqNo, none}], State);
+process_routing_confirm(MsgSeqNo, QRefs, #{dest := Dst = #{unconfirmed := Unconfirmed}} = State) when is_integer(MsgSeqNo) ->
+    XName = rabbit_misc:r(<<"/">>, exchange, <<>>),
+    State#{dest => Dst#{unconfirmed =>
+                            rabbit_confirms:insert(MsgSeqNo, QRefs, XName, Unconfirmed)}}.
+
+record_confirms([], State) ->
+    State;
+record_confirms(MXs, State = #{dest := Dst = #{confirmed := C,
+                                              confirmed_count := CC}}) ->
+    Num = length(MXs),
+    rabbit_shovel_behaviour:decr_remaining(
+      Num, State#{dest => Dst#{confirmed => [MXs | C],
+                               confirmed_count => CC + Num}}).
+
+record_rejects([], State) ->
+    State;
+record_rejects(MXs, State = #{dest := Dst = #{rejected := R,
+                                              rejected_count := RC}}) ->
+    Num = length(MXs),
+    rabbit_shovel_behaviour:decr_remaining(
+      Num, State#{dest => Dst#{rejected => [MXs | R],
+                               rejected_count => RC + Num}}).
+
+confirm(MsgSeqNos, QRef, State = #{dest := Dst = #{unconfirmed := UC}}) ->
+    {ConfirmMXs, UC1} = rabbit_confirms:confirm(MsgSeqNos, QRef, UC),
+    record_confirms(ConfirmMXs, State#{dest => Dst#{unconfirmed => UC1}}).
+
+send_nacks([], _, State) ->
+    State;
+send_nacks(Rs, Cs, State) ->
+    coalesce_and_send(Rs, Cs,
+                      fun(MsgSeqNo, Multiple, StateX) ->
+                              rabbit_shovel_behaviour:nack(MsgSeqNo, Multiple, StateX)
+                      end, State).
+
+send_confirms([], _, State) ->
+    State;
+send_confirms([MsgSeqNo], _, State) ->
+    rabbit_shovel_behaviour:ack(MsgSeqNo, false, State);
+send_confirms(Cs, Rs, State) ->
+    coalesce_and_send(Cs, Rs,
+                      fun(MsgSeqNo, Multiple, StateX) ->
+                              rabbit_shovel_behaviour:ack(MsgSeqNo, Multiple, StateX)
+                      end, State).
+
+coalesce_and_send(MsgSeqNos, NegativeMsgSeqNos, MkMsgFun,
+                  State = #{dest := #{unconfirmed := UC}}) ->
+    SMsgSeqNos = lists:usort(MsgSeqNos),
+    UnconfirmedCutoff = case rabbit_confirms:is_empty(UC) of
+                            true  -> lists:last(SMsgSeqNos) + 1;
+                            false -> rabbit_confirms:smallest(UC)
+                        end,
+    Cutoff = lists:min([UnconfirmedCutoff | NegativeMsgSeqNos]),
+    {Ms, Ss} = lists:splitwith(fun(X) -> X < Cutoff end, SMsgSeqNos),
+    State1 = case Ms of
+                 [] -> State;
+                 _  -> MkMsgFun(lists:last(Ms), true, State)
+             end,
+    lists:foldl(fun(SeqNo, S) ->
+                        MkMsgFun(SeqNo, false, S)
+                end, State1, Ss).
+
+%% Todo remove XName from confirm/unconfirm as we don't need it for local
+send_confirms_and_nacks(State = #{dest := #{confirmed := [],
+                                            rejected := []}}) ->
+    State;
+send_confirms_and_nacks(State = #{dest := Dst = #{confirmed := C,
+                                                  rejected := R}}) ->
+    Confirms = lists:append(C),
+    ConfirmMsgSeqNos = [MsgSeqNo || {MsgSeqNo, _} <- Confirms],
+    Rejects = lists:append(R),
+    RejectMsgSeqNos = [MsgSeqNo || {MsgSeqNo, _} <- Rejects],
+    State1 = #{dest := Dst2}
+        = send_confirms(ConfirmMsgSeqNos,
+                        RejectMsgSeqNos,
+                        State#{dest => Dst#{confirmed => [],
+                                            confirmed_count => 0}}),
+    send_nacks(RejectMsgSeqNos,
+               ConfirmMsgSeqNos,
+               State1#{dest => Dst2#{rejected => [],
+                                     rejected_count => 0}}).