chore(recorder, tests): add test for openai /v1/models (#3426)

# What does this PR do?

- [x] adds a test for the recorder's handling of /v1/models
- [x] adds a fix for /v1/models handling

## Test Plan

ci

llama_stack/testing/inference_recorder.py

@@ -7,6 +7,7 @@
 from __future__ import annotations  # for forward references
 
 import hashlib
+import inspect
 import json
 import os
 from collections.abc import Generator
@@ -198,16 +199,11 @@ def _model_identifiers_digest(endpoint: str, response: dict[str, Any]) -> str:
 
         Supported endpoints:
         - '/api/tags' (Ollama): response body has 'models': [ { name/model/digest/id/... }, ... ]
-        - '/v1/models' (OpenAI): response body has 'data': [ { id: ... }, ... ]
+        - '/v1/models' (OpenAI): response body is: [ { id: ... }, ... ]
         Returns a list of unique identifiers or None if structure doesn't match.
         """
-        body = response["body"]
-        if endpoint == "/api/tags":
-            items = body.get("models")
-            idents = [m.model for m in items]
-        else:
-            items = body.get("data")
-            idents = [m.id for m in items]
+        items = response["body"]
+        idents = [m.model if endpoint == "/api/tags" else m.id for m in items]
         return sorted(set(idents))
 
     identifiers = _extract_model_identifiers()
@@ -219,28 +215,22 @@ def _combine_model_list_responses(endpoint: str, records: list[dict[str, Any]])
     seen: dict[str, dict[str, Any]] = {}
     for rec in records:
         body = rec["response"]["body"]
-        if endpoint == "/api/tags":
-            items = body.models
-        elif endpoint == "/v1/models":
-            items = body.data
-        else:
-            items = []
-
-        for m in items:
-            if endpoint == "/v1/models":
+        if endpoint == "/v1/models":
+            for m in body:
                 key = m.id
-            else:
+                seen[key] = m
+        elif endpoint == "/api/tags":
+            for m in body.models:
                 key = m.model
-            seen[key] = m
+                seen[key] = m
 
     ordered = [seen[k] for k in sorted(seen.keys())]
     canonical = records[0]
     canonical_req = canonical.get("request", {})
     if isinstance(canonical_req, dict):
         canonical_req["endpoint"] = endpoint
-    if endpoint == "/v1/models":
-        body = {"data": ordered, "object": "list"}
-    else:
+    body = ordered
+    if endpoint == "/api/tags":
         from ollama import ListResponse
 
         body = ListResponse(models=ordered)
@@ -252,7 +242,10 @@ async def _patched_inference_method(original_method, self, client_type, endpoint
 
     if _current_mode == InferenceMode.LIVE or _current_storage is None:
         # Normal operation
-        return await original_method(self, *args, **kwargs)
+        if inspect.iscoroutinefunction(original_method):
+            return await original_method(self, *args, **kwargs)
+        else:
+            return original_method(self, *args, **kwargs)
 
     # Get base URL based on client type
     if client_type == "openai":
@@ -300,7 +293,14 @@ async def _patched_inference_method(original_method, self, client_type, endpoint
             )
 
     elif _current_mode == InferenceMode.RECORD:
-        response = await original_method(self, *args, **kwargs)
+        if inspect.iscoroutinefunction(original_method):
+            response = await original_method(self, *args, **kwargs)
+        else:
+            response = original_method(self, *args, **kwargs)
+
+        # we want to store the result of the iterator, not the iterator itself
+        if endpoint == "/v1/models":
+            response = [m async for m in response]
 
         request_data = {
             "method": method,
@@ -380,10 +380,14 @@ def patch_inference_clients():
             _original_methods["embeddings_create"], self, "openai", "/v1/embeddings", *args, **kwargs
         )
 
-    async def patched_models_list(self, *args, **kwargs):
-        return await _patched_inference_method(
-            _original_methods["models_list"], self, "openai", "/v1/models", *args, **kwargs
-        )
+    def patched_models_list(self, *args, **kwargs):
+        async def _iter():
+            for item in await _patched_inference_method(
+                _original_methods["models_list"], self, "openai", "/v1/models", *args, **kwargs
+            ):
+                yield item
+
+        return _iter()
 
     # Apply OpenAI patches
     AsyncChatCompletions.create = patched_chat_completions_create

tests/unit/distribution/test_inference_recordings.py

@@ -6,10 +6,11 @@
 
 import tempfile
 from pathlib import Path
-from unittest.mock import patch
+from unittest.mock import AsyncMock, Mock, patch
 
 import pytest
 from openai import AsyncOpenAI
+from openai.types.model import Model as OpenAIModel
 
 # Import the real Pydantic response types instead of using Mocks
 from llama_stack.apis.inference import (
@@ -158,7 +159,9 @@ class TestInferenceRecording:
             return real_openai_chat_response
 
         temp_storage_dir = temp_storage_dir / "test_recording_mode"
-        with patch("openai.resources.chat.completions.AsyncCompletions.create", side_effect=mock_create):
+        with patch(
+            "openai.resources.chat.completions.AsyncCompletions.create", new_callable=AsyncMock, side_effect=mock_create
+        ):
             with inference_recording(mode=InferenceMode.RECORD, storage_dir=str(temp_storage_dir)):
                 client = AsyncOpenAI(base_url="http://localhost:11434/v1", api_key="test")
 
@@ -184,7 +187,9 @@ class TestInferenceRecording:
 
         temp_storage_dir = temp_storage_dir / "test_replay_mode"
         # First, record a response
-        with patch("openai.resources.chat.completions.AsyncCompletions.create", side_effect=mock_create):
+        with patch(
+            "openai.resources.chat.completions.AsyncCompletions.create", new_callable=AsyncMock, side_effect=mock_create
+        ):
             with inference_recording(mode=InferenceMode.RECORD, storage_dir=str(temp_storage_dir)):
                 client = AsyncOpenAI(base_url="http://localhost:11434/v1", api_key="test")
 
@@ -213,6 +218,42 @@ class TestInferenceRecording:
                 # Verify the original method was NOT called
                 mock_create_patch.assert_not_called()
 
+    async def test_replay_mode_models(self, temp_storage_dir):
+        """Test that replay mode returns stored responses without making real model listing calls."""
+
+        async def _async_iterator(models):
+            for model in models:
+                yield model
+
+        models = [
+            OpenAIModel(id="foo", created=1, object="model", owned_by="test"),
+            OpenAIModel(id="bar", created=2, object="model", owned_by="test"),
+        ]
+
+        expected_ids = {m.id for m in models}
+
+        temp_storage_dir = temp_storage_dir / "test_replay_mode_models"
+
+        # baseline - mock works without recording
+        client = AsyncOpenAI(base_url="http://localhost:11434/v1", api_key="test")
+        client.models._get_api_list = Mock(return_value=_async_iterator(models))
+        assert {m.id async for m in client.models.list()} == expected_ids
+        client.models._get_api_list.assert_called_once()
+
+        # record the call
+        with inference_recording(mode=InferenceMode.RECORD, storage_dir=temp_storage_dir):
+            client = AsyncOpenAI(base_url="http://localhost:11434/v1", api_key="test")
+            client.models._get_api_list = Mock(return_value=_async_iterator(models))
+            assert {m.id async for m in client.models.list()} == expected_ids
+            client.models._get_api_list.assert_called_once()
+
+        # replay the call
+        with inference_recording(mode=InferenceMode.REPLAY, storage_dir=temp_storage_dir):
+            client = AsyncOpenAI(base_url="http://localhost:11434/v1", api_key="test")
+            client.models._get_api_list = Mock(return_value=_async_iterator(models))
+            assert {m.id async for m in client.models.list()} == expected_ids
+            client.models._get_api_list.assert_not_called()
+
     async def test_replay_missing_recording(self, temp_storage_dir):
         """Test that replay mode fails when no recording is found."""
         temp_storage_dir = temp_storage_dir / "test_replay_missing_recording"
@@ -233,7 +274,9 @@ class TestInferenceRecording:
 
         temp_storage_dir = temp_storage_dir / "test_embeddings_recording"
         # Record
-        with patch("openai.resources.embeddings.AsyncEmbeddings.create", side_effect=mock_create):
+        with patch(
+            "openai.resources.embeddings.AsyncEmbeddings.create", new_callable=AsyncMock, side_effect=mock_create
+        ):
             with inference_recording(mode=InferenceMode.RECORD, storage_dir=str(temp_storage_dir)):
                 client = AsyncOpenAI(base_url="http://localhost:11434/v1", api_key="test")