text and image metric (#6150)

Signed-off-by: zhuhh97 <zhuhonghan@huawei.com>
Signed-off-by: Gao Han <hgaoaf@connect.ust.hk>
Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>
Co-authored-by: Gao Han <hgaoaf@connect.ust.hk>

tests/diffusion/test_multiproc_engine_concurrency.py

@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: Apache-2.0
-# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
 
 import asyncio
 import multiprocessing as mp
@@ -1079,6 +1079,42 @@ class TestStageDiffusionClientErrorPropagation:
 
         assert client.get_diffusion_output_nowait() is None
 
+    def test_error_response_preserves_scheduler_metrics(self):
+        from vllm_omni.metrics import definitions as metric_defs
+
+        client = self._make_client()
+        client._response_socket.recv.side_effect = [b"message", zmq.Again()]
+        client._decoder.decode.return_value = {
+            "type": "error",
+            "request_id": "req-error",
+            "error": "gpu fault",
+            "metrics": {metric_defs.DIFFUSION_SCHEDULER_WAITING_KEY: 0},
+        }
+
+        output = client.get_diffusion_output_nowait()
+
+        assert output is not None
+        assert output.error == "gpu fault"
+        assert output.metrics[metric_defs.DIFFUSION_SCHEDULER_WAITING_KEY] == 0
+
+    def test_metrics_response_creates_metrics_only_output(self):
+        from vllm_omni.metrics import definitions as metric_defs
+        from vllm_omni.metrics.utils import DIFFUSION_METRICS_ONLY_REQUEST_ID
+
+        client = self._make_client()
+        client._response_socket.recv.side_effect = [b"message", zmq.Again()]
+        client._decoder.decode.return_value = {
+            "type": "metrics",
+            "metrics": {metric_defs.DIFFUSION_SCHEDULER_WAITING_KEY: 0},
+        }
+
+        output = client.get_diffusion_output_nowait()
+
+        assert output is not None
+        assert output.request_id == DIFFUSION_METRICS_ONLY_REQUEST_ID
+        assert output.error is None
+        assert output.metrics[metric_defs.DIFFUSION_SCHEDULER_WAITING_KEY] == 0
+
     def test_check_health_raises_when_proc_dead(self):
         """``check_health`` detects a dead subprocess via the manager's proc
         and raises ``EngineDeadError``, setting ``_engine_dead`` as a