feat: add optional metrics to all responses

docs/openapi_generator/pyopenapi/operations.py

@@ -10,9 +10,10 @@ import inspect
 import typing
 from dataclasses import dataclass
 from typing import Any, Callable, Dict, Iterable, Iterator, List, Optional, Tuple, Union
+from pydantic import BaseModel, create_model
 
 from llama_stack.apis.version import LLAMA_STACK_API_VERSION
-
+from llama_stack.apis.telemetry.telemetry import MetricEvent
 from termcolor import colored
 
 from ..strong_typing.inspection import get_signature
@@ -303,8 +304,28 @@ def get_endpoint_operations(
                     return typing._UnionGenericAlias(typing.Union, tuple(types))
                 else:
                     return t
+            def augment_response_with_metrics(t):
+                if t in (int, float, str, list):
+                    return t
+                elif typing.get_origin(t) is typing.Union:
+                    types = [augment_response_with_metrics(a) for a in typing.get_args(t)]
+                    return typing._UnionGenericAlias(typing.Union, tuple(types))
+                elif isinstance(t, type) and issubclass(t, BaseModel):
+                    if "metric_events" in t.model_fields:
+                        print(f"warning: {t.__name__} already has metric_events field")
+                        return t
+                    if "data" in t.model_fields:
+                        print(f"warning: {t.__name__} has a data field, metrics are not added")
+                        return t
+                    return create_model(
+                        t.__name__,
+                        __base__=t,
+                        metrics=(Optional[List[MetricEvent]], None)
+                    )
+                else:
+                    return t
 
-            response_type = process_type(return_type)
+            response_type = augment_response_with_metrics(process_type(return_type))
 
             if prefix in ["delete", "remove"]:
                 http_method = HTTPMethod.DELETE