[action] [PR:3837] Fix DPU restart message drop by Zmq lazy bind.

lib/orch_zmq_config.cpp

@@ -72,7 +72,10 @@ std::shared_ptr<swss::ZmqServer> swss::create_zmq_server(std::string zmq_address
     }
 
     SWSS_LOG_NOTICE("Create ZMQ server with address: %s, vrf: %s", zmq_address.c_str(), vrf.c_str());
-    return std::make_shared<ZmqServer>(zmq_address, vrf);
+
+    // To prevent message loss between ZmqServer's bind operation and the creation of ZmqProducerStateTable,
+    // use lazy binding and call bind() only after the handler has been registered.
+    return std::make_shared<ZmqServer>(zmq_address, vrf, true);
 }
 
 bool swss::get_feature_status(std::string feature, bool default_value)

orchagent/main.cpp

@@ -854,6 +854,14 @@ int main(int argc, char **argv)
         syncd_apply_view();
     }
 
+    if (zmq_server)
+    {
+        // To prevent message loss between ZmqServer's bind operation and the creation of ZmqProducerStateTable,
+        // use lazy binding and call bind() only after the handler has been registered.
+        zmq_server->bind();
+        SWSS_LOG_NOTICE("ZMQ channel on the northbound side of Orchagent successfully bound: %s, %s", zmq_server_address.c_str(), vrf.c_str());
+    }
+
     orchDaemon->start(heartBeatInterval);
 
     return 0;

tests/mock_tests/zmq_orch_ut.cpp

@@ -79,6 +79,7 @@ TEST(ZmqOrchTest, CreateZmqClient)
     auto zmq_client = swss::create_zmq_client(zmq_server_address);
 
     zmq_server->registerMessageHandler("test_db", "test_table", &zmq_handler);
+    zmq_server->bind();
 
     std::vector<KeyOpFieldsValuesTuple> value;
     zmq_client->sendMsg("test_db", "test_table", value);
@@ -127,4 +128,4 @@ TEST(ZmqOrchTest, GetFeatureStatusException)
     config_db.hset("DEVICE_METADATA|localhost", HGET_THROW_EXCEPTION_FIELD_NAME, "true");
     enabled = swss::get_feature_status(HGET_THROW_EXCEPTION_FIELD_NAME, false);
     EXPECT_FALSE(enabled);
-}
+}