Add Hosted VLLM rerank provider integration (#12738)

* Vllm rerank (#12737)

* Add Hosted VLLM rerank provider integration

This commit implements the Hosted VLLM rerank provider integration for LiteLLM. The integration includes:
Adding Hosted VLLM as a supported rerank provider in the main rerank function
Implementing the HostedVLLMRerank handler class for making API requests
Creating a transformation class to convert Hosted VLLM responses to LiteLLM's standardized format
The integration supports both synchronous and asynchronous rerank operations. API credentials can be provided directly or through environment variables (HOSTED_VLLM_API_KEY and HOSTED_VLLM_API_BASE).
Notable features:
Proper error handling for missing credentials
Standard response transformation
Support for common rerank parameters (top_n, return_documents, etc.)
Proper token usage tracking
This expands LiteLLM's rerank provider ecosystem to include Hosted VLLM alongside existing providers like Cohere, Together AI, Azure AI, and Bedrock.

* refactor(rerank): use base_llm_http_handler for hosted_vllm rerank

- Replace custom HostedVLLMRerank handler with base_llm_http_handler
- Implement proper HostedVLLMRerankConfig inheriting from BaseRerankConfig
- Follow Cohere-compatible implementation pattern
- Clean up unnecessary comments

* Fix lint errors in hosted_vllm rerank transformer: remove unused imports

* Fix linting errors in rerank transformation modules

* fix: resolve type errors in Hosted VLLM rerank module

---------

Co-authored-by: Philip D'Souza <philip.dsouza@macro4.com>
Co-authored-by: Philip D'Souza <philip.a.dsouza@gmail.com>

* added a few tests

---------

Co-authored-by: Philip D'Souza <philip.dsouza@macro4.com>
Co-authored-by: Philip D'Souza <philip.a.dsouza@gmail.com>
This commit is contained in:
Jugal D. Bhatt
2025-07-18 10:55:50 -07:00
committed by GitHub
co-authored by Philip D'Souza Philip D'Souza
parent 56eacd0a38
commit 7c49197f29
4 changed files with 319 additions and 4 deletions
+2 -3
View File
@@ -1,14 +1,13 @@
from typing import Any, Dict, List, Optional, Union
import httpx
import litellm
from litellm.litellm_core_utils.litellm_logging import Logging as LiteLLMLoggingObj
from litellm.llms.base_llm.chat.transformation import BaseLLMException
from litellm.llms.base_llm.rerank.transformation import BaseRerankConfig
from litellm.secret_managers.main import get_secret_str
from litellm.types.rerank import OptionalRerankParams, RerankRequest
from litellm.types.utils import RerankResponse
from litellm.types.rerank import OptionalRerankParams, RerankRequest, RerankResponse
from ..common_utils import CohereError
@@ -0,0 +1,202 @@
"""
Transformation logic for Hosted VLLM rerank
"""
import uuid
from typing import Any, Dict, List, Optional, Union
from litellm.types.rerank import (
RerankBilledUnits,
RerankResponse,
RerankResponseDocument,
RerankResponseMeta,
RerankResponseResult,
RerankTokens,
OptionalRerankParams,
RerankRequest,
)
import httpx
from litellm.litellm_core_utils.litellm_logging import Logging as LiteLLMLoggingObj
from litellm.llms.base_llm.chat.transformation import BaseLLMException
from litellm.llms.base_llm.rerank.transformation import BaseRerankConfig
from litellm.secret_managers.main import get_secret_str
class HostedVLLMRerankError(BaseLLMException):
def __init__(
self,
status_code: int,
message: str,
headers: Optional[Union[dict, httpx.Headers]] = None,
):
super().__init__(status_code=status_code, message=message, headers=headers)
class HostedVLLMRerankConfig(BaseRerankConfig):
def __init__(self) -> None:
pass
def get_complete_url(self, api_base: Optional[str], model: str) -> str:
if api_base:
# Remove trailing slashes and ensure clean base URL
api_base = api_base.rstrip("/")
if not api_base.endswith("/v1/rerank"):
api_base = f"{api_base}/v1/rerank"
return api_base
raise ValueError("api_base must be provided for Hosted VLLM rerank")
def get_supported_cohere_rerank_params(self, model: str) -> list:
return [
"query",
"documents",
"top_n",
"rank_fields",
"return_documents",
]
def map_cohere_rerank_params(
self,
non_default_params: Optional[dict],
model: str,
drop_params: bool,
query: str,
documents: List[Union[str, Dict[str, Any]]],
custom_llm_provider: Optional[str] = None,
top_n: Optional[int] = None,
rank_fields: Optional[List[str]] = None,
return_documents: Optional[bool] = True,
max_chunks_per_doc: Optional[int] = None,
max_tokens_per_doc: Optional[int] = None,
) -> OptionalRerankParams:
"""
Map parameters for Hosted VLLM rerank
"""
if max_chunks_per_doc is not None:
raise ValueError("Hosted VLLM does not support max_chunks_per_doc")
return OptionalRerankParams(
query=query,
documents=documents,
top_n=top_n,
rank_fields=rank_fields,
return_documents=return_documents,
)
def validate_environment(
self,
headers: dict,
model: str,
api_key: Optional[str] = None,
) -> dict:
if api_key is None:
api_key = get_secret_str("HOSTED_VLLM_API_KEY") or "fake-api-key"
default_headers = {
"Authorization": f"Bearer {api_key}",
"accept": "application/json",
"content-type": "application/json",
}
# If 'Authorization' is provided in headers, it overrides the default.
if "Authorization" in headers:
default_headers["Authorization"] = headers["Authorization"]
# Merge other headers, overriding any default ones except Authorization
return {**default_headers, **headers}
def transform_rerank_request(
self,
model: str,
optional_rerank_params: OptionalRerankParams,
headers: dict,
) -> dict:
if "query" not in optional_rerank_params:
raise ValueError("query is required for Hosted VLLM rerank")
if "documents" not in optional_rerank_params:
raise ValueError("documents is required for Hosted VLLM rerank")
rerank_request = RerankRequest(
model=model,
query=optional_rerank_params["query"],
documents=optional_rerank_params["documents"],
top_n=optional_rerank_params.get("top_n", None),
rank_fields=optional_rerank_params.get("rank_fields", None),
return_documents=optional_rerank_params.get("return_documents", None),
)
return rerank_request.model_dump(exclude_none=True)
def transform_rerank_response(
self,
model: str,
raw_response: httpx.Response,
model_response: RerankResponse,
logging_obj: LiteLLMLoggingObj,
api_key: Optional[str] = None,
request_data: dict = {},
optional_params: dict = {},
litellm_params: dict = {},
) -> RerankResponse:
"""
Process response from Hosted VLLM rerank API
"""
try:
raw_response_json = raw_response.json()
except Exception:
raise ValueError(
f"Error parsing response: {raw_response.text}, status_code={raw_response.status_code}"
)
return RerankResponse(**raw_response_json)
def get_error_class(
self, error_message: str, status_code: int, headers: Union[dict, httpx.Headers]
) -> BaseLLMException:
return HostedVLLMRerankError(message=error_message, status_code=status_code, headers=headers)
def _transform_response(self, response: dict) -> RerankResponse:
# Extract usage information
usage_data = response.get("usage", {})
_billed_units = RerankBilledUnits(total_tokens=usage_data.get("total_tokens", 0))
_tokens = RerankTokens(input_tokens=usage_data.get("total_tokens", 0))
rerank_meta = RerankResponseMeta(billed_units=_billed_units, tokens=_tokens)
# Extract results
_results: Optional[List[dict]] = response.get("results")
if _results is None:
raise ValueError(f"No results found in the response={response}")
rerank_results: List[RerankResponseResult] = []
for result in _results:
# Validate required fields exist
if not all(key in result for key in ["index", "relevance_score"]):
raise ValueError(f"Missing required fields in the result={result}")
# Get document data if it exists
document_data = result.get("document", {})
document = (
RerankResponseDocument(text=str(document_data.get("text", "")))
if document_data
else None
)
# Create typed result
rerank_result = RerankResponseResult(
index=int(result["index"]),
relevance_score=float(result["relevance_score"]),
)
# Only add document if it exists
if document:
rerank_result["document"] = document
rerank_results.append(rerank_result)
return RerankResponse(
id=response.get("id") or str(uuid.uuid4()),
results=rerank_results,
meta=rerank_meta,
)
+34 -1
View File
@@ -75,7 +75,7 @@ def rerank( # noqa: PLR0915
query: str,
documents: List[Union[str, Dict[str, Any]]],
custom_llm_provider: Optional[
Literal["cohere", "together_ai", "azure_ai", "infinity", "litellm_proxy"]
Literal["cohere", "together_ai", "azure_ai", "infinity", "litellm_proxy", "hosted_vllm"]
] = None,
top_n: Optional[int] = None,
rank_fields: Optional[List[str]] = None,
@@ -323,6 +323,39 @@ def rerank( # noqa: PLR0915
logging_obj=litellm_logging_obj,
client=client,
)
elif _custom_llm_provider == "hosted_vllm":
# Implement Hosted VLLM rerank logic
api_key = (
dynamic_api_key
or optional_params.api_key
or get_secret_str("HOSTED_VLLM_API_KEY")
)
api_base = (
dynamic_api_base
or optional_params.api_base
or get_secret_str("HOSTED_VLLM_API_BASE")
)
if api_base is None:
raise ValueError(
"api_base must be provided for Hosted VLLM rerank. Set in call or via HOSTED_VLLM_API_BASE env var."
)
response = base_llm_http_handler.rerank(
model=model,
custom_llm_provider=_custom_llm_provider,
provider_config=rerank_provider_config,
optional_rerank_params=optional_rerank_params,
logging_obj=litellm_logging_obj,
timeout=optional_params.timeout,
api_key=api_key,
api_base=api_base,
_is_async=_is_async,
headers=headers or litellm.headers or {},
client=client,
model_response=model_response,
)
else:
# Generic handler for all providers that use base_llm_http_handler
# Provider-specific logic (API key validation, URL generation, etc.)
@@ -0,0 +1,81 @@
import sys
import os
import pytest
from litellm.llms.hosted_vllm.rerank.transformation import HostedVLLMRerankConfig
from litellm.types.rerank import OptionalRerankParams, RerankResponse, RerankResponseResult, RerankResponseMeta, RerankBilledUnits, RerankTokens, RerankResponseDocument
class TestHostedVLLMRerankTransform:
def setup_method(self):
self.config = HostedVLLMRerankConfig()
self.model = "hosted-vllm-model"
def test_map_cohere_rerank_params_basic(self):
params = self.config.map_cohere_rerank_params(
non_default_params=None,
model=self.model,
drop_params=False,
query="test query",
documents=["doc1", "doc2"],
top_n=2,
rank_fields=["field1"],
return_documents=True,
)
assert params["query"] == "test query"
assert params["documents"] == ["doc1", "doc2"]
assert params["top_n"] == 2
assert params["rank_fields"] == ["field1"]
assert params["return_documents"] is True
def test_map_cohere_rerank_params_raises_on_max_chunks_per_doc(self):
with pytest.raises(ValueError, match="Hosted VLLM does not support max_chunks_per_doc"):
self.config.map_cohere_rerank_params(
non_default_params=None,
model=self.model,
drop_params=False,
query="test query",
documents=["doc1"],
max_chunks_per_doc=5
)
def test_get_complete_url(self):
base = "https://api.example.com"
url = self.config.get_complete_url(base, self.model)
assert url == "https://api.example.com/v1/rerank"
# Already ends with /v1/rerank
url2 = self.config.get_complete_url("https://api.example.com/v1/rerank", self.model)
assert url2 == "https://api.example.com/v1/rerank"
# Raises if api_base is None
with pytest.raises(ValueError):
self.config.get_complete_url(None, self.model)
def test_transform_response(self):
response_dict = {
"id": "abc123",
"results": [
{"index": 0, "relevance_score": 0.9, "document": {"text": "doc1 text"}},
{"index": 1, "relevance_score": 0.7, "document": {"text": "doc2 text"}},
],
"usage": {"total_tokens": 42}
}
result = self.config._transform_response(response_dict)
assert result.id == "abc123"
assert len(result.results) == 2
assert result.results[0]["index"] == 0
assert result.results[0]["relevance_score"] == 0.9
assert result.results[0]["document"]["text"] == "doc1 text"
assert result.meta["billed_units"]["total_tokens"] == 42
assert result.meta["tokens"]["input_tokens"] == 42
def test_transform_response_missing_results(self):
response_dict = {"id": "abc123", "usage": {"total_tokens": 10}}
with pytest.raises(ValueError, match="No results found in the response="):
self.config._transform_response(response_dict)
def test_transform_response_missing_required_fields(self):
response_dict = {
"id": "abc123",
"results": [{"relevance_score": 0.5}],
"usage": {"total_tokens": 10}
}
with pytest.raises(ValueError, match="Missing required fields in the result="):
self.config._transform_response(response_dict)