Fix error in protocol step (#75)

Author: yngvar-antonsson

CHANGELOG.md

@@ -6,6 +6,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+### Fixed
+
+- Protocol step error when the members list were cleared in process.
+
 ## [2.5.0] - 2025-03-06
 
 ### Added

membership.lua

@@ -514,16 +514,18 @@ local function _protocol_step()
     if sent_indirect > 0 then
         ack_data = wait_ack(uri, loop_now, opts.PROTOCOL_PERIOD_SECONDS * 1.0e6)
     end
+
+    -- check again in case if members list has been cleared
+    local member = members.get(uri)
+    if member == nil then
+        return
+    end
     if sent_indirect > 0 and ack_data ~= nil then
-        local member = members.get(uri)
-        if member == nil then
-            return
-        end
         -- calculate time difference between local time and member time
         local delta = _get_clock_delta(ack_data)
         members.set(uri, member.status, member.incarnation, { clock_delta = delta })
         return
-    elseif members.get(uri).status == opts.ALIVE then
+    elseif member.status == opts.ALIVE then
         local myself = members.get(advertise_uri)
         if myself.status ~= opts.ALIVE then
             opts.log_debug('Could not reach node: %s (%s myself)', uri, myself.status)