llama-stack-mirror/llama_stack/providers/inline/inference/meta_reference/inference.py
Ben Browning 2b2db5fbda
feat: OpenAI-Compatible models, completions, chat/completions (#1894)
# What does this PR do?

This stubs in some OpenAI server-side compatibility with three new
endpoints:

/v1/openai/v1/models
/v1/openai/v1/completions
/v1/openai/v1/chat/completions

This gives common inference apps using OpenAI clients the ability to
talk to Llama Stack using an endpoint like
http://localhost:8321/v1/openai/v1 .

The two "v1" instances in there isn't awesome, but the thinking is that
Llama Stack's API is v1 and then our OpenAI compatibility layer is
compatible with OpenAI V1. And, some OpenAI clients implicitly assume
the URL ends with "v1", so this gives maximum compatibility.

The openai models endpoint is implemented in the routing layer, and just
returns all the models Llama Stack knows about.

The following providers should be working with the new OpenAI
completions and chat/completions API:
* remote::anthropic (untested)
* remote::cerebras-openai-compat (untested)
* remote::fireworks (tested)
* remote::fireworks-openai-compat (untested)
* remote::gemini (untested)
* remote::groq-openai-compat (untested)
* remote::nvidia (tested)
* remote::ollama (tested)
* remote::openai (untested)
* remote::passthrough (untested)
* remote::sambanova-openai-compat (untested)
* remote::together (tested)
* remote::together-openai-compat (untested)
* remote::vllm (tested)

The goal to support this for every inference provider - proxying
directly to the provider's OpenAI endpoint for OpenAI-compatible
providers. For providers that don't have an OpenAI-compatible API, we'll
add a mixin to translate incoming OpenAI requests to Llama Stack
inference requests and translate the Llama Stack inference responses to
OpenAI responses.

This is related to #1817 but is a bit larger in scope than just chat
completions, as I have real use-cases that need the older completions
API as well.

## Test Plan

### vLLM

```
VLLM_URL="http://localhost:8000/v1" INFERENCE_MODEL="meta-llama/Llama-3.2-3B-Instruct" llama stack build --template remote-vllm --image-type venv --run

LLAMA_STACK_CONFIG=http://localhost:8321 INFERENCE_MODEL="meta-llama/Llama-3.2-3B-Instruct" python -m pytest -v tests/integration/inference/test_openai_completion.py --text-model "meta-llama/Llama-3.2-3B-Instruct"
```

### ollama
```
INFERENCE_MODEL="llama3.2:3b-instruct-q8_0" llama stack build --template ollama --image-type venv --run

LLAMA_STACK_CONFIG=http://localhost:8321 INFERENCE_MODEL="llama3.2:3b-instruct-q8_0" python -m pytest -v tests/integration/inference/test_openai_completion.py --text-model "llama3.2:3b-instruct-q8_0"
```



## Documentation

Run a Llama Stack distribution that uses one of the providers mentioned
in the list above. Then, use your favorite OpenAI client to send
completion or chat completion requests with the base_url set to
http://localhost:8321/v1/openai/v1 . Replace "localhost:8321" with the
host and port of your Llama Stack server, if different.

---------

Signed-off-by: Ben Browning <bbrownin@redhat.com>
2025-04-11 13:14:17 -07:00

492 lines
18 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import asyncio
import logging
import os
from typing import AsyncGenerator, List, Optional, Union
from termcolor import cprint
from llama_stack.apis.common.content_types import (
TextDelta,
ToolCallDelta,
ToolCallParseStatus,
)
from llama_stack.apis.inference import (
ChatCompletionRequest,
ChatCompletionResponse,
ChatCompletionResponseEvent,
ChatCompletionResponseEventType,
ChatCompletionResponseStreamChunk,
CompletionMessage,
CompletionRequest,
CompletionResponse,
CompletionResponseStreamChunk,
Inference,
InterleavedContent,
LogProbConfig,
Message,
ResponseFormat,
SamplingParams,
StopReason,
TokenLogProbs,
ToolChoice,
ToolConfig,
ToolDefinition,
ToolPromptFormat,
)
from llama_stack.apis.models import Model, ModelType
from llama_stack.models.llama.llama3.chat_format import ChatFormat as Llama3ChatFormat
from llama_stack.models.llama.llama3.tokenizer import Tokenizer as Llama3Tokenizer
from llama_stack.models.llama.llama4.chat_format import ChatFormat as Llama4ChatFormat
from llama_stack.models.llama.llama4.tokenizer import Tokenizer as Llama4Tokenizer
from llama_stack.models.llama.sku_list import resolve_model
from llama_stack.models.llama.sku_types import ModelFamily
from llama_stack.providers.datatypes import ModelsProtocolPrivate
from llama_stack.providers.utils.inference.embedding_mixin import (
SentenceTransformerEmbeddingMixin,
)
from llama_stack.providers.utils.inference.model_registry import (
ModelRegistryHelper,
build_hf_repo_model_entry,
)
from llama_stack.providers.utils.inference.openai_compat import (
OpenAIChatCompletionUnsupportedMixin,
OpenAICompletionUnsupportedMixin,
)
from llama_stack.providers.utils.inference.prompt_adapter import (
augment_content_with_response_format_prompt,
chat_completion_request_to_messages,
convert_request_to_raw,
)
from .config import MetaReferenceInferenceConfig
from .generators import Llama3Generator, Llama4Generator
from .model_parallel import LlamaModelParallelGenerator
log = logging.getLogger(__name__)
# there's a single model parallel process running serving the model. for now,
# we don't support multiple concurrent requests to this process.
SEMAPHORE = asyncio.Semaphore(1)
def llama3_builder_fn(config: MetaReferenceInferenceConfig, model_id: str, llama_model: Model) -> Llama3Generator:
return Llama3Generator(config, model_id, llama_model)
def llama4_builder_fn(config: MetaReferenceInferenceConfig, model_id: str, llama_model: Model) -> Llama4Generator:
return Llama4Generator(config, model_id, llama_model)
class MetaReferenceInferenceImpl(
OpenAICompletionUnsupportedMixin,
OpenAIChatCompletionUnsupportedMixin,
SentenceTransformerEmbeddingMixin,
Inference,
ModelsProtocolPrivate,
):
def __init__(self, config: MetaReferenceInferenceConfig) -> None:
self.config = config
self.model_id = None
self.llama_model = None
async def initialize(self) -> None:
pass
async def shutdown(self) -> None:
if self.config.create_distributed_process_group:
self.generator.stop()
async def unregister_model(self, model_id: str) -> None:
pass
async def register_model(self, model: Model) -> Model:
llama_model = (
resolve_model(model.metadata["llama_model"])
if "llama_model" in model.metadata
else resolve_model(model.identifier)
)
if llama_model is None:
raise ValueError(
"Please make sure your llama_model in model metadata or model identifier is in Llama SKU list"
)
self.model_registry_helper = ModelRegistryHelper(
[
build_hf_repo_model_entry(
llama_model.descriptor(),
llama_model.core_model_id.value,
)
],
)
model = await self.model_registry_helper.register_model(model)
if model.model_type == ModelType.embedding:
self._load_sentence_transformer_model(model.provider_resource_id)
# TODO: what is this?! you can't really specify skipping via model metadata
# kill this madness
if "skip_load" in model.metadata and model.metadata["skip_load"]:
return model
await self.load_model(model.identifier, llama_model)
return model
async def load_model(self, model_id, llama_model) -> None:
log.info(f"Loading model `{model_id}`")
if llama_model.model_family in {
ModelFamily.llama3,
ModelFamily.llama3_1,
ModelFamily.llama3_2,
ModelFamily.llama3_3,
}:
builder_fn = llama3_builder_fn
elif llama_model.model_family == ModelFamily.llama4:
builder_fn = llama4_builder_fn
else:
raise ValueError(f"Unsupported model family: {llama_model.model_family}")
builder_params = [self.config, model_id, llama_model]
if self.config.create_distributed_process_group:
self.generator = LlamaModelParallelGenerator(
model_parallel_size=self.config.model_parallel_size or llama_model.pth_file_count,
builder_fn=builder_fn,
builder_params=builder_params,
formatter=(
Llama4ChatFormat(Llama4Tokenizer.get_instance())
if llama_model.model_family == ModelFamily.llama4
else Llama3ChatFormat(Llama3Tokenizer.get_instance())
),
)
self.generator.start()
else:
self.generator = builder_fn(*builder_params)
self.model_id = model_id
self.llama_model = llama_model
def check_model(self, request) -> None:
if self.model_id is None or self.llama_model is None:
raise RuntimeError(
"No avaible model yet, please register your requested model or add your model in the resouces first"
)
elif request.model != self.model_id:
raise RuntimeError(f"Model mismatch: request model: {request.model} != loaded model: {self.model_id}")
async def completion(
self,
model_id: str,
content: InterleavedContent,
sampling_params: Optional[SamplingParams] = None,
response_format: Optional[ResponseFormat] = None,
stream: Optional[bool] = False,
logprobs: Optional[LogProbConfig] = None,
) -> Union[CompletionResponse, CompletionResponseStreamChunk]:
if sampling_params is None:
sampling_params = SamplingParams()
if logprobs:
assert logprobs.top_k == 1, f"Unexpected top_k={logprobs.top_k}"
content = augment_content_with_response_format_prompt(response_format, content)
request = CompletionRequest(
model=model_id,
content=content,
sampling_params=sampling_params,
response_format=response_format,
stream=stream,
logprobs=logprobs,
)
self.check_model(request)
request = await convert_request_to_raw(request)
if request.stream:
return self._stream_completion(request)
else:
return await self._nonstream_completion(request)
async def _stream_completion(self, request: CompletionRequest) -> AsyncGenerator:
tokenizer = self.generator.formatter.tokenizer
def impl():
stop_reason = None
for token_result in self.generator.completion(request):
if token_result.token == tokenizer.eot_id:
stop_reason = StopReason.end_of_turn
text = ""
elif token_result.token == tokenizer.eom_id:
stop_reason = StopReason.end_of_message
text = ""
else:
text = token_result.text
logprobs = None
if stop_reason is None:
if request.logprobs:
assert len(token_result.logprobs) == 1
logprobs = [TokenLogProbs(logprobs_by_token={token_result.text: token_result.logprobs[0]})]
yield CompletionResponseStreamChunk(
delta=text,
stop_reason=stop_reason,
logprobs=logprobs if request.logprobs else None,
)
if stop_reason is None:
yield CompletionResponseStreamChunk(
delta="",
stop_reason=StopReason.out_of_tokens,
)
if self.config.create_distributed_process_group:
async with SEMAPHORE:
for x in impl():
yield x
else:
for x in impl():
yield x
async def _nonstream_completion(self, request: CompletionRequest) -> CompletionResponse:
tokenizer = self.generator.formatter.tokenizer
def impl():
tokens = []
logprobs = []
stop_reason = None
for token_result in self.generator.completion(request):
tokens.append(token_result.token)
if token_result.token == tokenizer.eot_id:
stop_reason = StopReason.end_of_turn
elif token_result.token == tokenizer.eom_id:
stop_reason = StopReason.end_of_message
if request.logprobs:
assert len(token_result.logprobs) == 1
logprobs.append(TokenLogProbs(logprobs_by_token={token_result.text: token_result.logprobs[0]}))
if stop_reason is None:
stop_reason = StopReason.out_of_tokens
if tokens[-1] in self.generator.formatter.tokenizer.stop_tokens:
tokens = tokens[:-1]
content = self.generator.formatter.tokenizer.decode(tokens)
return CompletionResponse(
content=content,
stop_reason=stop_reason,
logprobs=logprobs if request.logprobs else None,
)
if self.config.create_distributed_process_group:
async with SEMAPHORE:
return impl()
else:
return impl()
async def chat_completion(
self,
model_id: str,
messages: List[Message],
sampling_params: Optional[SamplingParams] = None,
response_format: Optional[ResponseFormat] = None,
tools: Optional[List[ToolDefinition]] = None,
tool_choice: Optional[ToolChoice] = ToolChoice.auto,
tool_prompt_format: Optional[ToolPromptFormat] = None,
stream: Optional[bool] = False,
logprobs: Optional[LogProbConfig] = None,
tool_config: Optional[ToolConfig] = None,
) -> AsyncGenerator:
if sampling_params is None:
sampling_params = SamplingParams()
if logprobs:
assert logprobs.top_k == 1, f"Unexpected top_k={logprobs.top_k}"
# wrapper request to make it easier to pass around (internal only, not exposed to API)
request = ChatCompletionRequest(
model=model_id,
messages=messages,
sampling_params=sampling_params,
tools=tools or [],
response_format=response_format,
stream=stream,
logprobs=logprobs,
tool_config=tool_config,
)
self.check_model(request)
# augment and rewrite messages depending on the model
request.messages = chat_completion_request_to_messages(request, self.llama_model.core_model_id.value)
# download media and convert to raw content so we can send it to the model
request = await convert_request_to_raw(request)
if self.config.create_distributed_process_group:
if SEMAPHORE.locked():
raise RuntimeError("Only one concurrent request is supported")
if request.stream:
return self._stream_chat_completion(request)
else:
return await self._nonstream_chat_completion(request)
async def _nonstream_chat_completion(self, request: ChatCompletionRequest) -> ChatCompletionResponse:
tokenizer = self.generator.formatter.tokenizer
def impl():
tokens = []
logprobs = []
stop_reason = None
for token_result in self.generator.chat_completion(request):
if os.environ.get("LLAMA_MODELS_DEBUG", "0") == "1":
cprint(token_result.text, "cyan", end="")
tokens.append(token_result.token)
if token_result.token == tokenizer.eot_id:
stop_reason = StopReason.end_of_turn
elif token_result.token == tokenizer.eom_id:
stop_reason = StopReason.end_of_message
if request.logprobs:
assert len(token_result.logprobs) == 1
logprobs.append(TokenLogProbs(logprobs_by_token={token_result.text: token_result.logprobs[0]}))
if stop_reason is None:
stop_reason = StopReason.out_of_tokens
raw_message = self.generator.formatter.decode_assistant_message(tokens, stop_reason)
return ChatCompletionResponse(
completion_message=CompletionMessage(
content=raw_message.content,
stop_reason=raw_message.stop_reason,
tool_calls=raw_message.tool_calls,
),
logprobs=logprobs if request.logprobs else None,
)
if self.config.create_distributed_process_group:
async with SEMAPHORE:
return impl()
else:
return impl()
async def _stream_chat_completion(self, request: ChatCompletionRequest) -> AsyncGenerator:
tokenizer = self.generator.formatter.tokenizer
def impl():
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.start,
delta=TextDelta(text=""),
)
)
tokens = []
logprobs = []
stop_reason = None
ipython = False
for token_result in self.generator.chat_completion(request):
if os.environ.get("LLAMA_MODELS_DEBUG", "0") == "1":
cprint(token_result.text, "cyan", end="")
tokens.append(token_result.token)
if not ipython and token_result.text.startswith("<|python_tag|>"):
ipython = True
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call="",
parse_status=ToolCallParseStatus.started,
),
)
)
continue
if token_result.token == tokenizer.eot_id:
stop_reason = StopReason.end_of_turn
text = ""
elif token_result.token == tokenizer.eom_id:
stop_reason = StopReason.end_of_message
text = ""
else:
text = token_result.text
if ipython:
delta = ToolCallDelta(
tool_call=text,
parse_status=ToolCallParseStatus.in_progress,
)
else:
delta = TextDelta(text=text)
if stop_reason is None:
if request.logprobs:
assert len(token_result.logprobs) == 1
logprobs.append(TokenLogProbs(logprobs_by_token={token_result.text: token_result.logprobs[0]}))
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=delta,
stop_reason=stop_reason,
logprobs=logprobs if request.logprobs else None,
)
)
if stop_reason is None:
stop_reason = StopReason.out_of_tokens
message = self.generator.formatter.decode_assistant_message(tokens, stop_reason)
parsed_tool_calls = len(message.tool_calls) > 0
if ipython and not parsed_tool_calls:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call="",
parse_status=ToolCallParseStatus.failed,
),
stop_reason=stop_reason,
)
)
for tool_call in message.tool_calls:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call=tool_call,
parse_status=ToolCallParseStatus.succeeded,
),
stop_reason=stop_reason,
)
)
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.complete,
delta=TextDelta(text=""),
stop_reason=stop_reason,
)
)
if self.config.create_distributed_process_group:
async with SEMAPHORE:
for x in impl():
yield x
else:
for x in impl():
yield x