From fbc33159e45146ca4783f58aff218d4544bf7496 Mon Sep 17 00:00:00 2001
From: Michael Klishin <michaelklishin@icloud.com>
Date: Fri, 10 Jan 2025 22:04:18 -0500
Subject: [PATCH] HTTP API: make GET /api/aliveness-test a no-op

This follows the decision that was made for
'rabbitm-diagnostics node_health_check' which
is a no-op as of 4.0.0 following a few years of
deprecation.

The justification is very similar:

1. There is no such thing as "One True Health Check".
   A single health check is too coarse-grained to
   explain what specifically is not right about
   cluster state
2. Indivual fine-grained health checks have been
   available for a few years now, see
   https://www.rabbitmq.com/docs/monitoring#health-checks
3. This particular check tests something that
   effectively never fails, based on my 14+
   years of RabbitMQ contributions and user support
   of all shapes and forms
4. This check uses a deprecated feature: non-exclusive
   non-durable/transient classic queues

If something about this health check is worth
preserving, we can always add a new one
under GET /api/health/checks/*

Closes #13047.

(cherry picked from commit ad906c978678d4ebffee52e2439756648b739033)
---
 .../src/rabbit_mgmt_wm_aliveness_test.erl     | 30 +++----------------
 1 file changed, 4 insertions(+), 26 deletions(-)

diff --git a/deps/rabbitmq_management/src/rabbit_mgmt_wm_aliveness_test.erl b/deps/rabbitmq_management/src/rabbit_mgmt_wm_aliveness_test.erl
index 92074a1f11e1..c1a59696a0e5 100644
--- a/deps/rabbitmq_management/src/rabbit_mgmt_wm_aliveness_test.erl
+++ b/deps/rabbitmq_management/src/rabbit_mgmt_wm_aliveness_test.erl
@@ -35,37 +35,15 @@ resource_exists(ReqData, Context) ->
         end, ReqData, Context}.
 
 to_json(ReqData, Context) ->
+    %% This health check is deprecated and is now a no-op.
+    %% More specific health checks under GET /api/health/checks/* should be used instead.
+    %% https://www.rabbitmq.com/docs/monitoring#health-checks
     rabbit_mgmt_util:with_channel(
         rabbit_mgmt_util:vhost(ReqData),
         ReqData,
         Context,
-        fun(Ch) ->
-            #'queue.declare_ok'{queue = ?QUEUE} = amqp_channel:call(Ch, #'queue.declare'{
-                queue = ?QUEUE
-            }),
-            ok = amqp_channel:call(Ch, #'basic.publish'{routing_key = ?QUEUE}, #amqp_msg{
-                payload = <<"test_message">>
-            }),
-            case amqp_channel:call(Ch, #'basic.get'{queue = ?QUEUE, no_ack = true}) of
-                {#'basic.get_ok'{}, _} ->
-                    %% Don't delete the queue. If this is pinged every few
-                    %% seconds we don't want to create a mnesia transaction
-                    %% each time.
-                    rabbit_mgmt_util:reply([{status, ok}], ReqData, Context);
-                #'basic.get_empty'{} ->
-                    Reason = <<"aliveness-test queue is empty">>,
-                    failure(Reason, ReqData, Context);
-                Error ->
-                    Reason = rabbit_data_coercion:to_binary(Error),
-                    failure(Reason, ReqData, Context)
-            end
-        end
+        fun(_Ch) -> rabbit_mgmt_util:reply([{status, ok}], ReqData, Context) end
     ).
 
-failure(Reason, ReqData0, Context0) ->
-    Body = #{status => failed, reason => Reason},
-    {Response, ReqData1, Context1} = rabbit_mgmt_util:reply(Body, ReqData0, Context0),
-    {stop, cowboy_req:reply(?HEALTH_CHECK_FAILURE_STATUS, #{}, Response, ReqData1), Context1}.
-
 is_authorized(ReqData, Context) ->
     rabbit_mgmt_util:is_authorized_vhost(ReqData, Context).