# ========= Copyright 2023-2024 @ CAMEL-AI.org. All Rights Reserved. =========
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ========= Copyright 2023-2024 @ CAMEL-AI.org. All Rights Reserved. =========
import os
import subprocess
from typing import Any, Dict, List, Optional, Union
from openai import OpenAI, Stream
from camel.configs import VLLM_API_PARAMS, VLLMConfig
from camel.messages import OpenAIMessage
from camel.models import BaseModelBackend
from camel.types import (
ChatCompletion,
ChatCompletionChunk,
ModelType,
)
from camel.utils import BaseTokenCounter, OpenAITokenCounter
# flake8: noqa: E501
[docs]
class VLLMModel(BaseModelBackend):
r"""vLLM service interface.
Args:
model_type (Union[ModelType, str]): Model for which a backend is
created.
model_config_dict (Optional[Dict[str, Any]], optional): A dictionary
that will be fed into:obj:`openai.ChatCompletion.create()`. If
:obj:`None`, :obj:`VLLMConfig().as_dict()` will be used.
(default: :obj:`None`)
api_key (Optional[str], optional): The API key for authenticating with
the model service. vLLM doesn't need API key, it would be ignored
if set. (default: :obj:`None`)
url (Optional[str], optional): The url to the model service. If not
provided, :obj:`"http://localhost:8000/v1"` will be used.
(default: :obj:`None`)
token_counter (Optional[BaseTokenCounter], optional): Token counter to
use for the model. If not provided, :obj:`OpenAITokenCounter(
ModelType.GPT_4O_MINI)` will be used.
(default: :obj:`None`)
References:
https://docs.vllm.ai/en/latest/serving/openai_compatible_server.html
"""
def __init__(
self,
model_type: Union[ModelType, str],
model_config_dict: Optional[Dict[str, Any]] = None,
api_key: Optional[str] = None,
url: Optional[str] = None,
token_counter: Optional[BaseTokenCounter] = None,
) -> None:
if model_config_dict is None:
model_config_dict = VLLMConfig().as_dict()
url = url or os.environ.get("VLLM_BASE_URL")
super().__init__(
model_type, model_config_dict, api_key, url, token_counter
)
if not self._url:
self._start_server()
# Use OpenAI cilent as interface call vLLM
self._client = OpenAI(
timeout=180,
max_retries=3,
api_key="EMPTY", # required but ignored
base_url=self._url,
)
def _start_server(self) -> None:
r"""Starts the vllm server in a subprocess."""
try:
subprocess.Popen(
["vllm", "server", "--port", "8000"],
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
self._url = "http://localhost:8000/v1"
print(
f"vllm server started on {self._url} "
f"for {self.model_type} model."
)
except Exception as e:
print(f"Failed to start vllm server: {e}.")
@property
def token_counter(self) -> BaseTokenCounter:
r"""Initialize the token counter for the model backend.
Returns:
BaseTokenCounter: The token counter following the model's
tokenization style.
"""
if not self._token_counter:
self._token_counter = OpenAITokenCounter(ModelType.GPT_4O_MINI)
return self._token_counter
[docs]
def check_model_config(self):
r"""Check whether the model configuration contains any
unexpected arguments to vLLM API.
Raises:
ValueError: If the model configuration dictionary contains any
unexpected arguments to OpenAI API.
"""
for param in self.model_config_dict:
if param not in VLLM_API_PARAMS:
raise ValueError(
f"Unexpected argument `{param}` is "
"input into vLLM model backend."
)
[docs]
def run(
self,
messages: List[OpenAIMessage],
) -> Union[ChatCompletion, Stream[ChatCompletionChunk]]:
r"""Runs inference of OpenAI chat completion.
Args:
messages (List[OpenAIMessage]): Message list with the chat history
in OpenAI API format.
Returns:
Union[ChatCompletion, Stream[ChatCompletionChunk]]:
`ChatCompletion` in the non-stream mode, or
`Stream[ChatCompletionChunk]` in the stream mode.
"""
response = self._client.chat.completions.create(
messages=messages,
model=self.model_type,
**self.model_config_dict,
)
return response
@property
def stream(self) -> bool:
r"""Returns whether the model is in stream mode, which sends partial
results each time.
Returns:
bool: Whether the model is in stream mode.
"""
return self.model_config_dict.get('stream', False)
