langchain/libs/partners/mistralai/langchain_mistralai/chat_models.py
2024-01-09 16:21:39 -08:00

394 lines
14 KiB
Python

from __future__ import annotations
import importlib.util
import logging
from typing import (
Any,
AsyncIterator,
Callable,
Dict,
Iterator,
List,
Optional,
Tuple,
Type,
Union,
)
from langchain_core.callbacks import (
AsyncCallbackManagerForLLMRun,
CallbackManagerForLLMRun,
)
from langchain_core.language_models.chat_models import (
BaseChatModel,
agenerate_from_stream,
generate_from_stream,
)
from langchain_core.language_models.llms import create_base_retry_decorator
from langchain_core.messages import (
AIMessage,
AIMessageChunk,
BaseMessage,
BaseMessageChunk,
ChatMessage,
ChatMessageChunk,
HumanMessage,
HumanMessageChunk,
SystemMessage,
SystemMessageChunk,
)
from langchain_core.outputs import (
ChatGeneration,
ChatGenerationChunk,
ChatResult,
)
from langchain_core.pydantic_v1 import SecretStr, root_validator
from langchain_core.utils import convert_to_secret_str, get_from_dict_or_env
# TODO: Remove 'type: ignore' once mistralai has stubs or py.typed marker.
from mistralai.async_client import MistralAsyncClient # type: ignore[import]
from mistralai.client import MistralClient # type: ignore[import]
from mistralai.constants import ( # type: ignore[import]
ENDPOINT as DEFAULT_MISTRAL_ENDPOINT,
)
from mistralai.exceptions import ( # type: ignore[import]
MistralAPIException,
MistralConnectionException,
MistralException,
)
from mistralai.models.chat_completion import ( # type: ignore[import]
ChatCompletionResponse as MistralChatCompletionResponse,
)
from mistralai.models.chat_completion import ( # type: ignore[import]
ChatMessage as MistralChatMessage,
)
from mistralai.models.chat_completion import ( # type: ignore[import]
DeltaMessage as MistralDeltaMessage,
)
logger = logging.getLogger(__name__)
def _create_retry_decorator(
llm: ChatMistralAI,
run_manager: Optional[
Union[AsyncCallbackManagerForLLMRun, CallbackManagerForLLMRun]
] = None,
) -> Callable[[Any], Any]:
"""Returns a tenacity retry decorator, preconfigured to handle exceptions"""
errors = [
MistralException,
MistralAPIException,
MistralConnectionException,
]
return create_base_retry_decorator(
error_types=errors, max_retries=llm.max_retries, run_manager=run_manager
)
def _convert_mistral_chat_message_to_message(
_message: MistralChatMessage,
) -> BaseMessage:
role = _message.role
if role == "user":
return HumanMessage(content=_message.content)
elif role == "assistant":
return AIMessage(content=_message.content)
elif role == "system":
return SystemMessage(content=_message.content)
else:
return ChatMessage(content=_message.content, role=role)
async def acompletion_with_retry(
llm: ChatMistralAI,
run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> Any:
"""Use tenacity to retry the async completion call."""
retry_decorator = _create_retry_decorator(llm, run_manager=run_manager)
@retry_decorator
async def _completion_with_retry(**kwargs: Any) -> Any:
stream = kwargs.pop("stream", False)
if stream:
return llm.async_client.chat_stream(**kwargs)
else:
return await llm.async_client.chat(**kwargs)
return await _completion_with_retry(**kwargs)
def _convert_delta_to_message_chunk(
_obj: MistralDeltaMessage, default_class: Type[BaseMessageChunk]
) -> BaseMessageChunk:
role = getattr(_obj, "role")
content = getattr(_obj, "content", "")
if role == "user" or default_class == HumanMessageChunk:
return HumanMessageChunk(content=content)
elif role == "assistant" or default_class == AIMessageChunk:
return AIMessageChunk(content=content)
elif role == "system" or default_class == SystemMessageChunk:
return SystemMessageChunk(content=content)
elif role or default_class == ChatMessageChunk:
return ChatMessageChunk(content=content, role=role)
else:
return default_class(content=content)
def _convert_message_to_mistral_chat_message(
message: BaseMessage,
) -> MistralChatMessage:
if isinstance(message, ChatMessage):
mistral_message = MistralChatMessage(role=message.role, content=message.content)
elif isinstance(message, HumanMessage):
mistral_message = MistralChatMessage(role="user", content=message.content)
elif isinstance(message, AIMessage):
mistral_message = MistralChatMessage(role="assistant", content=message.content)
elif isinstance(message, SystemMessage):
mistral_message = MistralChatMessage(role="system", content=message.content)
else:
raise ValueError(f"Got unknown type {message}")
return mistral_message
class ChatMistralAI(BaseChatModel):
"""A chat model that uses the MistralAI API."""
client: MistralClient = None #: :meta private:
async_client: MistralAsyncClient = None #: :meta private:
mistral_api_key: Optional[SecretStr] = None
endpoint: str = DEFAULT_MISTRAL_ENDPOINT
max_retries: int = 5
timeout: int = 120
max_concurrent_requests: int = 64
model: str = "mistral-small"
temperature: float = 0.7
max_tokens: Optional[int] = None
top_p: float = 1
"""Decode using nucleus sampling: consider the smallest set of tokens whose
probability sum is at least top_p. Must be in the closed interval [0.0, 1.0]."""
random_seed: Optional[int] = None
safe_mode: bool = False
@property
def _default_params(self) -> Dict[str, Any]:
"""Get the default parameters for calling the API."""
defaults = {
"model": self.model,
"temperature": self.temperature,
"max_tokens": self.max_tokens,
"top_p": self.top_p,
"random_seed": self.random_seed,
"safe_mode": self.safe_mode,
}
filtered = {k: v for k, v in defaults.items() if v is not None}
return filtered
@property
def _client_params(self) -> Dict[str, Any]:
"""Get the parameters used for the client."""
return self._default_params
def completion_with_retry(
self, run_manager: Optional[CallbackManagerForLLMRun] = None, **kwargs: Any
) -> Any:
"""Use tenacity to retry the completion call."""
retry_decorator = _create_retry_decorator(self, run_manager=run_manager)
@retry_decorator
def _completion_with_retry(**kwargs: Any) -> Any:
stream = kwargs.pop("stream", False)
if stream:
return self.client.chat_stream(**kwargs)
else:
return self.client.chat(**kwargs)
return _completion_with_retry(**kwargs)
@root_validator()
def validate_environment(cls, values: Dict) -> Dict:
"""Validate api key, python package exists, temperature, and top_p."""
mistralai_spec = importlib.util.find_spec("mistralai")
if mistralai_spec is None:
raise MistralException(
"Could not find mistralai python package. "
"Please install it with `pip install mistralai`"
)
values["mistral_api_key"] = convert_to_secret_str(
get_from_dict_or_env(
values, "mistral_api_key", "MISTRAL_API_KEY", default=""
)
)
values["client"] = MistralClient(
api_key=values["mistral_api_key"].get_secret_value(),
endpoint=values["endpoint"],
max_retries=values["max_retries"],
timeout=values["timeout"],
)
values["async_client"] = MistralAsyncClient(
api_key=values["mistral_api_key"].get_secret_value(),
endpoint=values["endpoint"],
max_retries=values["max_retries"],
timeout=values["timeout"],
max_concurrent_requests=values["max_concurrent_requests"],
)
if values["temperature"] is not None and not 0 <= values["temperature"] <= 1:
raise ValueError("temperature must be in the range [0.0, 1.0]")
if values["top_p"] is not None and not 0 <= values["top_p"] <= 1:
raise ValueError("top_p must be in the range [0.0, 1.0]")
return values
def _generate(
self,
messages: List[BaseMessage],
stop: Optional[List[str]] = None,
run_manager: Optional[CallbackManagerForLLMRun] = None,
stream: Optional[bool] = None,
**kwargs: Any,
) -> ChatResult:
should_stream = stream if stream is not None else False
if should_stream:
stream_iter = self._stream(
messages, stop=stop, run_manager=run_manager, **kwargs
)
return generate_from_stream(stream_iter)
message_dicts, params = self._create_message_dicts(messages, stop)
params = {**params, **kwargs}
response = self.completion_with_retry(
messages=message_dicts, run_manager=run_manager, **params
)
return self._create_chat_result(response)
def _create_chat_result(
self, response: MistralChatCompletionResponse
) -> ChatResult:
generations = []
for res in response.choices:
finish_reason = getattr(res, "finish_reason")
if finish_reason:
finish_reason = finish_reason.value
gen = ChatGeneration(
message=_convert_mistral_chat_message_to_message(res.message),
generation_info={"finish_reason": finish_reason},
)
generations.append(gen)
token_usage = getattr(response, "usage")
token_usage = vars(token_usage) if token_usage else {}
llm_output = {"token_usage": token_usage, "model": self.model}
return ChatResult(generations=generations, llm_output=llm_output)
def _create_message_dicts(
self, messages: List[BaseMessage], stop: Optional[List[str]]
) -> Tuple[List[MistralChatMessage], Dict[str, Any]]:
params = self._client_params
if stop is not None:
if "stop" in params:
raise ValueError("`stop` found in both the input and default params.")
params["stop"] = stop
message_dicts = [_convert_message_to_mistral_chat_message(m) for m in messages]
return message_dicts, params
def _stream(
self,
messages: List[BaseMessage],
stop: Optional[List[str]] = None,
run_manager: Optional[CallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> Iterator[ChatGenerationChunk]:
message_dicts, params = self._create_message_dicts(messages, stop)
params = {**params, **kwargs, "stream": True}
default_chunk_class = AIMessageChunk
for chunk in self.completion_with_retry(
messages=message_dicts, run_manager=run_manager, **params
):
if len(chunk.choices) == 0:
continue
delta = chunk.choices[0].delta
if not delta.content:
continue
chunk = _convert_delta_to_message_chunk(delta, default_chunk_class)
default_chunk_class = chunk.__class__
yield ChatGenerationChunk(message=chunk)
if run_manager:
run_manager.on_llm_new_token(chunk.content)
async def _astream(
self,
messages: List[BaseMessage],
stop: Optional[List[str]] = None,
run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> AsyncIterator[ChatGenerationChunk]:
message_dicts, params = self._create_message_dicts(messages, stop)
params = {**params, **kwargs, "stream": True}
default_chunk_class = AIMessageChunk
async for chunk in await acompletion_with_retry(
self, messages=message_dicts, run_manager=run_manager, **params
):
if len(chunk.choices) == 0:
continue
delta = chunk.choices[0].delta
if not delta.content:
continue
chunk = _convert_delta_to_message_chunk(delta, default_chunk_class)
default_chunk_class = chunk.__class__
yield ChatGenerationChunk(message=chunk)
if run_manager:
await run_manager.on_llm_new_token(chunk.content)
async def _agenerate(
self,
messages: List[BaseMessage],
stop: Optional[List[str]] = None,
run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
stream: Optional[bool] = None,
**kwargs: Any,
) -> ChatResult:
should_stream = stream if stream is not None else False
if should_stream:
stream_iter = self._astream(
messages=messages, stop=stop, run_manager=run_manager, **kwargs
)
return await agenerate_from_stream(stream_iter)
message_dicts, params = self._create_message_dicts(messages, stop)
params = {**params, **kwargs}
response = await acompletion_with_retry(
self, messages=message_dicts, run_manager=run_manager, **params
)
return self._create_chat_result(response)
@property
def _identifying_params(self) -> Dict[str, Any]:
"""Get the identifying parameters."""
return self._default_params
@property
def _llm_type(self) -> str:
"""Return type of chat model."""
return "mistralai-chat"
@property
def lc_secrets(self) -> Dict[str, str]:
return {"mistral_api_key": "MISTRAL_API_KEY"}
@classmethod
def is_lc_serializable(cls) -> bool:
"""Return whether this model can be serialized by Langchain."""
return True
@classmethod
def get_lc_namespace(cls) -> List[str]:
"""Get the namespace of the langchain object."""
return ["langchain", "chat_models", "mistralai"]