Unregister from peer discovery backend on shutdown

References #1143.

2 files changed, 26 insertions, 3 deletions

diff --git a/src/rabbit.erl b/src/rabbit.erl
index a0c66f1cec..be75321714 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -22,7 +22,7 @@
          stop_and_halt/0, await_startup/0, status/0, is_running/0, alarms/0,
          is_running/1, environment/0, rotate_logs/0, force_event_refresh/1,
          start_fhc/0]).
--export([start/2, stop/1]).
+-export([start/2, stop/1, prep_stop/1]).
 -export([start_apps/1, stop_apps/1]).
 -export([log_locations/0, config_files/0, decrypt_config/2]). %% for testing and mgmt-agent
 
@@ -472,6 +472,7 @@ stop() ->
     rabbit_log:info("RabbitMQ is asked to stop...~n", []),
     Apps = ?APPS ++ rabbit_plugins:active(),
     stop_apps(app_utils:app_dependency_order(Apps, true)),
+    rabbit_peer_discovery:unregister(),
     rabbit_log:info("Successfully stopped RabbitMQ and its dependencies~n", []).
 
 stop_and_halt() ->
@@ -753,6 +754,10 @@ start(normal, []) ->
             Error
     end.
 
+prep_stop(State) ->
+  rabbit_peer_discovery:unregister(),
+  State.
+
 stop(_State) ->
     ok = rabbit_alarm:stop(),
     ok = case rabbit_mnesia:is_clustered() of
diff --git a/src/rabbit_peer_discovery.erl b/src/rabbit_peer_discovery.erl
index c0b554e3b3..a93c63ac05 100644
--- a/src/rabbit_peer_discovery.erl
+++ b/src/rabbit_peer_discovery.erl
@@ -21,7 +21,8 @@
 %%
 
 -export([discover_cluster_nodes/0, backend/0, node_type/0,
-         normalize/1, format_discovered_nodes/1, log_configured_backend/0]).
+         normalize/1, format_discovered_nodes/1, log_configured_backend/0,
+         unregister/0]).
 -export([append_node_prefix/1, node_prefix/0]).
 
 -define(DEFAULT_BACKEND,   rabbit_peer_discovery_classic_config).
@@ -72,6 +73,24 @@ discover_cluster_nodes() ->
     normalize(Backend:list_nodes()).
 
 
+-spec unregister() -> ok.
+
+unregister() ->
+  Backend = backend(),
+  rabbit_log:info("Will unregister with peer discovery backend ~s", [Backend]),
+  case Backend:unregister() of
+    ok             -> ok;
+    {error, Error} ->
+      rabbit_log:error("Failed to unregister with peer discovery backend ~s: ~p",
+        [Backend, Error]),
+      ok
+  end.
+
+
+%%
+%% Implementation
+%%
+
 -spec normalize(Nodes :: list() |
                 {Nodes :: list(), NodeType :: rabbit_types:node_type()} |
                 {ok, Nodes :: list()} |
@@ -90,7 +109,6 @@ normalize({ok, {Nodes, NodeType}}) when is_list(Nodes) andalso is_atom(NodeType)
 normalize({error, Reason}) ->
   {error, Reason}.
 
-
 -spec format_discovered_nodes(Nodes :: list()) -> string().
 
 format_discovered_nodes(Nodes) ->