Litellm router disable fallbacks (#6743)

* bump: version 1.52.6 → 1.52.7

* feat(router.py): enable dynamically disabling fallbacks

Allows for enabling/disabling fallbacks per key

* feat(litellm_pre_call_utils.py): support setting 'disable_fallbacks' on litellm key

* test: fix test

litellm/proxy/litellm_pre_call_utils.py

@@ -274,6 +274,51 @@ class LiteLLMProxyRequestSetup:
         )
         return user_api_key_logged_metadata
 
+    @staticmethod
+    def add_key_level_controls(
+        key_metadata: dict, data: dict, _metadata_variable_name: str
+    ):
+        data = data.copy()
+        if "cache" in key_metadata:
+            data["cache"] = {}
+            if isinstance(key_metadata["cache"], dict):
+                for k, v in key_metadata["cache"].items():
+                    if k in SupportedCacheControls:
+                        data["cache"][k] = v
+
+        ## KEY-LEVEL SPEND LOGS / TAGS
+        if "tags" in key_metadata and key_metadata["tags"] is not None:
+            if "tags" in data[_metadata_variable_name] and isinstance(
+                data[_metadata_variable_name]["tags"], list
+            ):
+                data[_metadata_variable_name]["tags"].extend(key_metadata["tags"])
+            else:
+                data[_metadata_variable_name]["tags"] = key_metadata["tags"]
+        if "spend_logs_metadata" in key_metadata and isinstance(
+            key_metadata["spend_logs_metadata"], dict
+        ):
+            if "spend_logs_metadata" in data[_metadata_variable_name] and isinstance(
+                data[_metadata_variable_name]["spend_logs_metadata"], dict
+            ):
+                for key, value in key_metadata["spend_logs_metadata"].items():
+                    if (
+                        key not in data[_metadata_variable_name]["spend_logs_metadata"]
+                    ):  # don't override k-v pair sent by request (user request)
+                        data[_metadata_variable_name]["spend_logs_metadata"][
+                            key
+                        ] = value
+            else:
+                data[_metadata_variable_name]["spend_logs_metadata"] = key_metadata[
+                    "spend_logs_metadata"
+                ]
+
+        ## KEY-LEVEL DISABLE FALLBACKS
+        if "disable_fallbacks" in key_metadata and isinstance(
+            key_metadata["disable_fallbacks"], bool
+        ):
+            data["disable_fallbacks"] = key_metadata["disable_fallbacks"]
+        return data
+
 
 async def add_litellm_data_to_request(  # noqa: PLR0915
     data: dict,
@@ -389,37 +434,11 @@ async def add_litellm_data_to_request(  # noqa: PLR0915
 
     ### KEY-LEVEL Controls
     key_metadata = user_api_key_dict.metadata
-    if "cache" in key_metadata:
-        data["cache"] = {}
-        if isinstance(key_metadata["cache"], dict):
-            for k, v in key_metadata["cache"].items():
-                if k in SupportedCacheControls:
-                    data["cache"][k] = v
-
-    ## KEY-LEVEL SPEND LOGS / TAGS
-    if "tags" in key_metadata and key_metadata["tags"] is not None:
-        if "tags" in data[_metadata_variable_name] and isinstance(
-            data[_metadata_variable_name]["tags"], list
-        ):
-            data[_metadata_variable_name]["tags"].extend(key_metadata["tags"])
-        else:
-            data[_metadata_variable_name]["tags"] = key_metadata["tags"]
-    if "spend_logs_metadata" in key_metadata and isinstance(
-        key_metadata["spend_logs_metadata"], dict
-    ):
-        if "spend_logs_metadata" in data[_metadata_variable_name] and isinstance(
-            data[_metadata_variable_name]["spend_logs_metadata"], dict
-        ):
-            for key, value in key_metadata["spend_logs_metadata"].items():
-                if (
-                    key not in data[_metadata_variable_name]["spend_logs_metadata"]
-                ):  # don't override k-v pair sent by request (user request)
-                    data[_metadata_variable_name]["spend_logs_metadata"][key] = value
-        else:
-            data[_metadata_variable_name]["spend_logs_metadata"] = key_metadata[
-                "spend_logs_metadata"
-            ]
-
+    data = LiteLLMProxyRequestSetup.add_key_level_controls(
+        key_metadata=key_metadata,
+        data=data,
+        _metadata_variable_name=_metadata_variable_name,
+    )
     ## TEAM-LEVEL SPEND LOGS/TAGS
     team_metadata = user_api_key_dict.team_metadata or {}
     if "tags" in team_metadata and team_metadata["tags"] is not None:

litellm/router.py

@@ -2610,6 +2610,7 @@ class Router:
         If it fails after num_retries, fall back to another model group
         """
         model_group: Optional[str] = kwargs.get("model")
+        disable_fallbacks: Optional[bool] = kwargs.pop("disable_fallbacks", False)
         fallbacks: Optional[List] = kwargs.get("fallbacks", self.fallbacks)
         context_window_fallbacks: Optional[List] = kwargs.get(
             "context_window_fallbacks", self.context_window_fallbacks
@@ -2637,7 +2638,7 @@ class Router:
             original_model_group: Optional[str] = kwargs.get("model")  # type: ignore
             fallback_failure_exception_str = ""
 
-            if original_model_group is None:
+            if disable_fallbacks is True or original_model_group is None:
                 raise e
 
             input_kwargs = {

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "litellm"
-version = "1.52.6"
+version = "1.52.7"
 description = "Library to easily interface with LLM API providers"
 authors = ["BerriAI"]
 license = "MIT"
@@ -91,7 +91,7 @@ requires = ["poetry-core", "wheel"]
 build-backend = "poetry.core.masonry.api"
 
 [tool.commitizen]
-version = "1.52.6"
+version = "1.52.7"
 version_files = [
     "pyproject.toml:^version"
 ]

tests/local_testing/test_router_fallbacks.py

@@ -1455,3 +1455,46 @@ async def test_router_fallbacks_default_and_model_specific_fallbacks(sync_mode):
     assert isinstance(
         exc_info.value, litellm.AuthenticationError
     ), f"Expected AuthenticationError, but got {type(exc_info.value).__name__}"
+
+
+@pytest.mark.asyncio
+async def test_router_disable_fallbacks_dynamically():
+    from litellm.router import run_async_fallback
+
+    router = Router(
+        model_list=[
+            {
+                "model_name": "bad-model",
+                "litellm_params": {
+                    "model": "openai/my-bad-model",
+                    "api_key": "my-bad-api-key",
+                },
+            },
+            {
+                "model_name": "good-model",
+                "litellm_params": {
+                    "model": "gpt-4o",
+                    "api_key": os.getenv("OPENAI_API_KEY"),
+                },
+            },
+        ],
+        fallbacks=[{"bad-model": ["good-model"]}],
+        default_fallbacks=["good-model"],
+    )
+
+    with patch.object(
+        router,
+        "log_retry",
+        new=MagicMock(return_value=None),
+    ) as mock_client:
+        try:
+            resp = await router.acompletion(
+                model="bad-model",
+                messages=[{"role": "user", "content": "Hey, how's it going?"}],
+                disable_fallbacks=True,
+            )
+            print(resp)
+        except Exception as e:
+            print(e)
+
+        mock_client.assert_not_called()

tests/proxy_unit_tests/test_proxy_server.py

@@ -1500,6 +1500,31 @@ async def test_add_callback_via_key_litellm_pre_call_utils(
         assert new_data["failure_callback"] == expected_failure_callbacks
 
 
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    "disable_fallbacks_set",
+    [
+        True,
+        False,
+    ],
+)
+async def test_disable_fallbacks_by_key(disable_fallbacks_set):
+    from litellm.proxy.litellm_pre_call_utils import LiteLLMProxyRequestSetup
+
+    key_metadata = {"disable_fallbacks": disable_fallbacks_set}
+    existing_data = {
+        "model": "azure/chatgpt-v-2",
+        "messages": [{"role": "user", "content": "write 1 sentence poem"}],
+    }
+    data = LiteLLMProxyRequestSetup.add_key_level_controls(
+        key_metadata=key_metadata,
+        data=existing_data,
+        _metadata_variable_name="metadata",
+    )
+
+    assert data["disable_fallbacks"] == disable_fallbacks_set
+
+
 @pytest.mark.asyncio
 @pytest.mark.parametrize(
     "callback_type, expected_success_callbacks, expected_failure_callbacks",