Fix: Prepend simtime to ZMQ write() payload for consistency (Issue #244)

Author: GaneshPatil7517

concore.py

@@ -375,7 +375,13 @@ def write(port_identifier, name, val, delta=0):
         try:
             # Keep ZMQ payloads JSON-serializable by normalizing numpy types.
             zmq_val = convert_numpy_to_python(val)
-            zmq_p.send_json_with_retry(zmq_val)
+            if isinstance(zmq_val, list):
+                # Prepend simtime to match file-based write behavior
+                payload = [simtime + delta] + zmq_val
+                zmq_p.send_json_with_retry(payload)
+                simtime += delta
+            else:
+                zmq_p.send_json_with_retry(zmq_val)
         except zmq.error.ZMQError as e:
             logging.error(f"ZMQ write error on port {port_identifier} (name: {name}): {e}")
         except Exception as e:

tests/test_concore.py

@@ -236,11 +236,16 @@ def send_json_with_retry(self, message):
         dummy = DummyPort()
         concore.zmq_ports["test_zmq"] = dummy
 
+        # Reset simtime for predictable test behavior
+        concore.simtime = 0
+
         payload = [np.int64(7), np.float64(3.5), {"x": np.float32(1.25)}]
         concore.write("test_zmq", "data", payload)
 
         assert dummy.sent is not None
-        assert dummy.sent == [7, 3.5, {"x": 1.25}]
-        assert not isinstance(dummy.sent[0], np.generic)
+        # ZMQ write now prepends simtime (0 in this case) to match file-based write behavior
+        assert dummy.sent == [0, 7, 3.5, {"x": 1.25}]
+        # Data values (after simtime) should be converted from numpy types
         assert not isinstance(dummy.sent[1], np.generic)
-        assert not isinstance(dummy.sent[2]["x"], np.generic)
+        assert not isinstance(dummy.sent[2], np.generic)
+        assert not isinstance(dummy.sent[3]["x"], np.generic)