fix(batches): keep the team key on the team host when a request sends only api_base

A request api_base now replaces the team deployment's api_base only when the
request also brings its own api_key, and a non-string api_key or api_base is
ignored, as on the merge base.

litellm/proxy/openai_files_endpoints/common_utils.py

@@ -43,7 +43,6 @@ FILE_LIST_CONTINUATION_CHUNK_SIZE: Final = 500
 BATCH_CREATE_HIDDEN_PARAM: Final = "batch_create"
 LITELLM_EXECUTED_BATCH_ID_PREFIX: Final = "litellm_batch_"
 EXPLICIT_CREDENTIAL_KEYS: Final = frozenset({"api_key", "api_base", "litellm_credential_name"})
-_REQUEST_CREDENTIAL_KEYS: Final = frozenset({"api_key", "api_base"})
 
 
 def validate_file_list_limit(limit: int | None) -> None:
@@ -649,8 +648,18 @@ def get_team_provider_credentials(
     return None
 
 
-def explicit_request_credentials(data: Mapping[str, object]) -> Mapping[str, object]:
-    return MappingProxyType({key: value for key, value in data.items() if key in _REQUEST_CREDENTIAL_KEYS and value})
+def _non_empty_string(value: object) -> str | None:
+    return value if isinstance(value, str) and value else None
+
+
+def explicit_request_credentials(data: Mapping[str, object]) -> Mapping[str, str]:
+    api_key: Final = _non_empty_string(data.get("api_key"))
+    if api_key is None:
+        return MappingProxyType({})
+    api_base: Final = _non_empty_string(data.get("api_base"))
+    if api_base is None:
+        return MappingProxyType({"api_key": api_key})
+    return MappingProxyType({"api_key": api_key, "api_base": api_base})
 
 
 def apply_team_provider_credentials(
@@ -664,9 +673,10 @@ def apply_team_provider_credentials(
     ``get_team_provider_credentials`` and merge them into ``data`` in-place.
     Leaves ``data`` untouched when no authorized deployment matches, so the
     caller falls back to environment-variable credentials exactly as before.
-    An ``api_key`` or ``api_base`` the request carries itself (a provider key
-    forwarded with ``forward_llm_provider_auth_headers``) replaces the
-    deployment's, as on chat completions.
+    An ``api_key`` the request carries itself (a provider key forwarded with
+    ``forward_llm_provider_auth_headers``) replaces the deployment's, and the
+    request's ``api_base`` replaces the deployment's only alongside that key,
+    so the deployment's key never goes to a host the caller picked.
     """
     credentials: Final = get_team_provider_credentials(
         llm_router=llm_router,

tests/unit/proxy/openai_files_endpoint/test_files_common_utils.py

@@ -722,12 +722,23 @@ def test_a_restricted_key_outside_the_team_wildcard_never_resolves_its_credentia
         ({}, "team-openai-key", "https://team.example/v1"),
         ({"api_key": ""}, "team-openai-key", "https://team.example/v1"),
         ({"api_key": "sk-forwarded"}, "sk-forwarded", "https://team.example/v1"),
-        ({"api_base": "https://caller.example/v1"}, "team-openai-key", "https://caller.example/v1"),
+        ({"api_base": "https://caller.example/v1"}, "team-openai-key", "https://team.example/v1"),
+        (
+            {"api_key": "sk-forwarded", "api_base": "https://caller.example/v1"},
+            "sk-forwarded",
+            "https://caller.example/v1",
+        ),
+        ({"api_key": 123}, "team-openai-key", "https://team.example/v1"),
+        (
+            {"api_key": "sk-forwarded", "api_base": ["https://caller.example/v1"]},
+            "sk-forwarded",
+            "https://team.example/v1",
+        ),
         ({"litellm_credential_name": "no-such-credential"}, "team-openai-key", "https://team.example/v1"),
     ],
 )
-def test_a_key_or_base_the_request_carries_replaces_only_that_part_of_the_team_credentials(
-    request_credentials: dict[str, str], sent_api_key: str, sent_api_base: str
+def test_the_team_key_only_goes_to_the_team_host_unless_the_request_brings_its_own_key(
+    request_credentials: dict[str, object], sent_api_key: str, sent_api_base: str
 ):
     data: Final[dict[str, object]] = dict(request_credentials)