From 0061944e9cc5d2590f9291ce968f8cf8692c4a78 Mon Sep 17 00:00:00 2001
From: Diana Parra Corbacho <diana.parra-corbacho@broadcom.com>
Date: Wed, 21 Aug 2024 10:38:38 +0200
Subject: [PATCH] Cancel AMQP stream consumer when local stream member is
 deleted

The consumer reader process is gone and there is no way to recover
it as the node does not have a member of the stream anymore,
so it should be cancelled/detached.
---
 deps/rabbit/BUILD.bazel                       |  2 +-
 deps/rabbit/src/rabbit_stream_coordinator.erl |  6 +++
 deps/rabbit/src/rabbit_stream_queue.erl       |  4 +-
 .../rabbit/test/rabbit_stream_queue_SUITE.erl | 42 +++++++++++++++++++
 4 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/deps/rabbit/BUILD.bazel b/deps/rabbit/BUILD.bazel
index c91cd890ff2c..5922b3d03617 100644
--- a/deps/rabbit/BUILD.bazel
+++ b/deps/rabbit/BUILD.bazel
@@ -832,7 +832,7 @@ rabbitmq_integration_suite(
     additional_beam = [
         ":test_queue_utils_beam",
     ],
-    shard_count = 19,
+    shard_count = 20,
     deps = [
         "@proper//:erlang_app",
     ],
diff --git a/deps/rabbit/src/rabbit_stream_coordinator.erl b/deps/rabbit/src/rabbit_stream_coordinator.erl
index 0846dd58d1e0..12c10c5e4ddc 100644
--- a/deps/rabbit/src/rabbit_stream_coordinator.erl
+++ b/deps/rabbit/src/rabbit_stream_coordinator.erl
@@ -1747,6 +1747,12 @@ eval_listener({P, member}, {ListNode, ListMPid0}, {Lsts0, Effs0},
                                         {queue_event, QRef,
                                          {stream_local_member_change, MemberPid}},
                                         cast} | Efs]};
+                     (_MNode, #member{state = {running, _, MemberPid},
+                                      role = {replica, _},
+                                      target = deleted}, {_, Efs}) ->
+                          {MemberPid, [{send_msg, P,
+                                        {queue_event, QRef, deleted_replica},
+                                        cast} | Efs]};
                      (_N, _M, Acc) ->
                           %% not a replica, nothing to do
                           Acc
diff --git a/deps/rabbit/src/rabbit_stream_queue.erl b/deps/rabbit/src/rabbit_stream_queue.erl
index e36ad708eb9a..6ee619e0e0ff 100644
--- a/deps/rabbit/src/rabbit_stream_queue.erl
+++ b/deps/rabbit/src/rabbit_stream_queue.erl
@@ -626,7 +626,9 @@ handle_event(_QName, {stream_local_member_change, Pid},
                          end, #{}, Readers0),
     {ok, State#stream_client{local_pid = Pid, readers = Readers1}, []};
 handle_event(_QName, eol, #stream_client{name = Name}) ->
-    {eol, [{unblock, Name}]}.
+    {eol, [{unblock, Name}]};
+handle_event(QName, deleted_replica, State) ->
+    {ok, State, [{queue_down, QName}]}.
 
 is_recoverable(Q) ->
     Node = node(),
diff --git a/deps/rabbit/test/rabbit_stream_queue_SUITE.erl b/deps/rabbit/test/rabbit_stream_queue_SUITE.erl
index 3d09d901caf9..3a74b4753bd0 100644
--- a/deps/rabbit/test/rabbit_stream_queue_SUITE.erl
+++ b/deps/rabbit/test/rabbit_stream_queue_SUITE.erl
@@ -34,6 +34,7 @@ all() ->
      {group, cluster_size_3},
      {group, cluster_size_3_1},
      {group, cluster_size_3_2},
+     {group, cluster_size_3_3},
      {group, cluster_size_3_parallel_1},
      {group, cluster_size_3_parallel_2},
      {group, cluster_size_3_parallel_3},
@@ -79,6 +80,7 @@ groups() ->
      {cluster_size_3_2, [], [recover,
                              declare_with_node_down_1,
                              declare_with_node_down_2]},
+     {cluster_size_3_3, [], [consume_while_deleting_replica]},
      {cluster_size_3_parallel_1, [parallel], [
                                               delete_replica,
                                               delete_last_replica,
@@ -207,6 +209,7 @@ init_per_group1(Group, Config) ->
                       cluster_size_3_parallel_5 -> 3;
                       cluster_size_3_1 -> 3;
                       cluster_size_3_2 -> 3;
+                      cluster_size_3_3 -> 3;
                       unclustered_size_3_1 -> 3;
                       unclustered_size_3_2 -> 3;
                       unclustered_size_3_3 -> 3;
@@ -1649,6 +1652,45 @@ consume_from_replica(Config) ->
     receive_batch(Ch2, 0, 99),
     rabbit_ct_broker_helpers:rpc(Config, 0, ?MODULE, delete_testcase_queue, [Q]).
 
+consume_while_deleting_replica(Config) ->
+    [Server1, _, Server3] = rabbit_ct_broker_helpers:get_node_configs(Config, nodename),
+
+    Ch1 = rabbit_ct_client_helpers:open_channel(Config, Server1),
+    Q = ?config(queue_name, Config),
+
+    ?assertEqual({'queue.declare_ok', Q, 0, 0},
+                 declare(Config, Server1, Q, [{<<"x-queue-type">>, longstr, <<"stream">>}])),
+
+    rabbit_ct_helpers:await_condition(
+      fun () ->
+              Info = find_queue_info(Config, 1, [online]),
+              length(proplists:get_value(online, Info)) == 3
+      end),
+
+    Ch2 = rabbit_ct_client_helpers:open_channel(Config, Server3),
+    qos(Ch2, 10, false),
+
+    CTag = atom_to_binary(?FUNCTION_NAME),
+    subscribe(Ch2, Q, false, 0, CTag),
+
+    %% Delete replica in node 3
+    rabbit_ct_broker_helpers:rpc(Config, 0, rabbit_stream_queue,
+                                 delete_replica, [<<"/">>, Q, Server3]),
+
+    publish_confirm(Ch1, Q, [<<"msg1">> || _ <- lists:seq(1, 100)]),
+
+    %% no messages should be received
+    receive
+        #'basic.cancel'{consumer_tag = CTag} ->
+            ok;
+        {_, #amqp_msg{}} ->
+            exit(unexpected_message)
+    after 30000 ->
+            exit(missing_consumer_cancel)
+    end,
+
+    rabbit_ct_broker_helpers:rpc(Config, 0, ?MODULE, delete_testcase_queue, [Q]).
+
 consume_credit(Config) ->
     [Server | _] = rabbit_ct_broker_helpers:get_node_configs(Config, nodename),