Mark expelled instances as left

CHANGELOG.rst

@@ -24,6 +24,8 @@ Changed
 
 - Update ``membership`` dependency to `2.4.6 <https://github.com/tarantool/membership/releases/tag/2.4.6>`_.
 
+- Expelled instances are now marked as ``left`` in ``membership``.
+
 -------------------------------------------------------------------------------
 [2.13.0] - 2024-11-28
 -------------------------------------------------------------------------------

cartridge/confapplier.lua

@@ -292,6 +292,7 @@ local function apply_config(clusterwide_config)
     if failover.is_leader() then
         for _, uuid, _ in fun.filter(topology.expelled, topology_cfg.servers) do
             box.space._cluster.index.uuid:delete(uuid)
+            membership.mark_left(topology_cfg.servers[uuid].uri)
         end
     end
 

test/integration/expel_test.lua

@@ -9,7 +9,7 @@ g.before_all(function()
         datadir = fio.tempdir(),
         use_vshard = false,
         server_command = helpers.entrypoint('srv_basic'),
-        cookie = helpers.random_cookie(),
+        cookie = 'secret', --helpers.random_cookie(),
         replicasets = {{
             alias = 'A',
             roles = {},
@@ -93,4 +93,14 @@ function g.test_api()
         g.A1.net_box.space._cluster:select(),
         {{1, g.r1_uuid}, {3, g.r3_uuid}}
     )
+
+    -- Check explicitly that expelled leader has left membership. Just in case also.
+
+    g.cluster:retrying({timeout = 10}, function ()
+        local ret = g.A1:exec(function()
+            local membership = require('membership')
+            return membership.members()
+        end)
+        t.assert_equals(ret[g.cluster:server('A-2').advertise_uri].status, 'left', ret)
+    end)
 end