litellm/litellm/proxy/pass_through_endpoints/streaming_handler.py
Cursor Agent 8759413312
refactor: trim explanatory comments from streaming-flush fix
Strip module-level docstrings and per-test/per-block prose from the
LIT-2642 fix and tests. Keep one short comment in each streaming site
that flags the GeneratorExit-vs-Exception subtlety, since that's the
non-obvious reason the flush lives in finally rather than after the loop.

Pure cleanup; no behavior change. All 12 regression tests still pass.

Co-authored-by: Mateo Wang <mateo-berri@users.noreply.github.com>
2026-04-30 02:39:28 +00:00

249 lines
10 KiB
Python

import asyncio
from datetime import datetime
from typing import List, Optional
import httpx
import litellm
from litellm._logging import verbose_proxy_logger
from litellm.litellm_core_utils.litellm_logging import Logging as LiteLLMLoggingObj
from litellm.litellm_core_utils.thread_pool_executor import executor
from litellm.proxy._types import PassThroughEndpointLoggingResultValues
from litellm.proxy.common_request_processing import ProxyBaseLLMRequestProcessing
from litellm.types.passthrough_endpoints.pass_through_endpoints import EndpointType
from litellm.types.utils import StandardPassThroughResponseObject
from .llm_provider_handlers.anthropic_passthrough_logging_handler import (
AnthropicPassthroughLoggingHandler,
)
from .llm_provider_handlers.openai_passthrough_logging_handler import (
OpenAIPassthroughLoggingHandler,
)
from .llm_provider_handlers.vertex_passthrough_logging_handler import (
VertexPassthroughLoggingHandler,
)
from .success_handler import PassThroughEndpointLogging
class PassThroughStreamingHandler:
@staticmethod
async def chunk_processor(
response: httpx.Response,
request_body: Optional[dict],
litellm_logging_obj: LiteLLMLoggingObj,
endpoint_type: EndpointType,
start_time: datetime,
passthrough_success_handler_obj: PassThroughEndpointLogging,
url_route: str,
):
raw_bytes: List[bytes] = []
logging_scheduled = False
model_name = PassThroughStreamingHandler._extract_model_for_cost_injection(
request_body=request_body,
url_route=url_route,
endpoint_type=endpoint_type,
litellm_logging_obj=litellm_logging_obj,
)
try:
async for chunk in response.aiter_bytes():
raw_bytes.append(chunk)
if (
getattr(litellm, "include_cost_in_streaming_usage", False)
and model_name
):
if endpoint_type == EndpointType.VERTEX_AI:
if "streamRawPredict" in url_route or "rawPredict" in url_route:
modified_chunk = ProxyBaseLLMRequestProcessing._process_chunk_with_cost_injection(
chunk, model_name
)
if modified_chunk is not None:
chunk = modified_chunk
elif endpoint_type == EndpointType.ANTHROPIC:
modified_chunk = ProxyBaseLLMRequestProcessing._process_chunk_with_cost_injection(
chunk, model_name
)
if modified_chunk is not None:
chunk = modified_chunk
yield chunk
except Exception as e:
verbose_proxy_logger.error(f"Error in chunk_processor: {str(e)}")
raise
finally:
# GeneratorExit (raised on client disconnect) is not caught by
# `except Exception`; the finally block ensures partial usage
# still gets logged for spend tracking. See LIT-2642.
if not logging_scheduled and raw_bytes:
logging_scheduled = True
try:
asyncio.create_task(
PassThroughStreamingHandler._route_streaming_logging_to_handler(
litellm_logging_obj=litellm_logging_obj,
passthrough_success_handler_obj=passthrough_success_handler_obj,
url_route=url_route,
request_body=request_body or {},
endpoint_type=endpoint_type,
start_time=start_time,
raw_bytes=raw_bytes,
end_time=datetime.now(),
)
)
except Exception as e:
verbose_proxy_logger.error(
f"Error scheduling chunk_processor logging: {str(e)}"
)
@staticmethod
async def _route_streaming_logging_to_handler(
litellm_logging_obj: LiteLLMLoggingObj,
passthrough_success_handler_obj: PassThroughEndpointLogging,
url_route: str,
request_body: dict,
endpoint_type: EndpointType,
start_time: datetime,
raw_bytes: List[bytes],
end_time: datetime,
model: Optional[str] = None,
):
"""
Route the logging for the collected chunks to the appropriate handler
Supported endpoint types:
- Anthropic
- Vertex AI
- OpenAI
"""
try:
all_chunks = PassThroughStreamingHandler._convert_raw_bytes_to_str_lines(
raw_bytes
)
standard_logging_response_object: Optional[
PassThroughEndpointLoggingResultValues
] = None
kwargs: dict = {}
if endpoint_type == EndpointType.ANTHROPIC:
anthropic_passthrough_logging_handler_result = AnthropicPassthroughLoggingHandler._handle_logging_anthropic_collected_chunks(
litellm_logging_obj=litellm_logging_obj,
passthrough_success_handler_obj=passthrough_success_handler_obj,
url_route=url_route,
request_body=request_body,
endpoint_type=endpoint_type,
start_time=start_time,
all_chunks=all_chunks,
end_time=end_time,
)
standard_logging_response_object = (
anthropic_passthrough_logging_handler_result["result"]
)
kwargs = anthropic_passthrough_logging_handler_result["kwargs"]
elif endpoint_type == EndpointType.VERTEX_AI:
vertex_passthrough_logging_handler_result = VertexPassthroughLoggingHandler._handle_logging_vertex_collected_chunks(
litellm_logging_obj=litellm_logging_obj,
passthrough_success_handler_obj=passthrough_success_handler_obj,
url_route=url_route,
request_body=request_body,
endpoint_type=endpoint_type,
start_time=start_time,
all_chunks=all_chunks,
end_time=end_time,
model=model,
)
standard_logging_response_object = (
vertex_passthrough_logging_handler_result["result"]
)
kwargs = vertex_passthrough_logging_handler_result["kwargs"]
elif endpoint_type == EndpointType.OPENAI:
openai_passthrough_logging_handler_result = OpenAIPassthroughLoggingHandler._handle_logging_openai_collected_chunks(
litellm_logging_obj=litellm_logging_obj,
passthrough_success_handler_obj=passthrough_success_handler_obj,
url_route=url_route,
request_body=request_body,
endpoint_type=endpoint_type,
start_time=start_time,
all_chunks=all_chunks,
end_time=end_time,
)
standard_logging_response_object = (
openai_passthrough_logging_handler_result["result"]
)
kwargs = openai_passthrough_logging_handler_result["kwargs"]
if standard_logging_response_object is None:
standard_logging_response_object = StandardPassThroughResponseObject(
response=f"cannot parse chunks to standard response object. Chunks={all_chunks}"
)
await litellm_logging_obj.async_success_handler(
result=standard_logging_response_object,
start_time=start_time,
end_time=end_time,
cache_hit=False,
**kwargs,
)
if (
litellm_logging_obj._should_run_sync_callbacks_for_async_calls()
is False
):
return
executor.submit(
litellm_logging_obj.success_handler,
result=standard_logging_response_object,
end_time=end_time,
cache_hit=False,
start_time=start_time,
**kwargs,
)
except Exception as e:
verbose_proxy_logger.error(
f"Error in _route_streaming_logging_to_handler: {str(e)}"
)
@staticmethod
def _extract_model_for_cost_injection(
request_body: Optional[dict],
url_route: str,
endpoint_type: EndpointType,
litellm_logging_obj: LiteLLMLoggingObj,
) -> Optional[str]:
"""
Extract model name for cost injection from various sources.
"""
# Try to get model from request body
if request_body:
model = request_body.get("model")
if model:
return model
# Try to get model from logging object
if hasattr(litellm_logging_obj, "model_call_details"):
model = litellm_logging_obj.model_call_details.get("model")
if model:
return model
# For Vertex AI, try to extract from URL
if endpoint_type == EndpointType.VERTEX_AI:
model = VertexPassthroughLoggingHandler.extract_model_from_url(url_route)
if model and model != "unknown":
return model
return None
@staticmethod
def _convert_raw_bytes_to_str_lines(raw_bytes: List[bytes]) -> List[str]:
"""
Converts a list of raw bytes into a list of string lines, similar to aiter_lines()
Args:
raw_bytes: List of bytes chunks from aiter.bytes()
Returns:
List of string lines, with each line being a complete data: {} chunk
"""
# Combine all bytes and decode to string
combined_str = b"".join(raw_bytes).decode("utf-8")
# Split by newlines and filter out empty lines
lines = [line.strip() for line in combined_str.split("\n") if line.strip()]
return lines