Source code for langchain_core.outputs.chat_generation
from __future__ import annotations
from typing import Any, Dict, List, Literal
from langchain_core.messages import BaseMessage, BaseMessageChunk
from langchain_core.outputs.generation import Generation
from langchain_core.pydantic_v1 import root_validator
from langchain_core.utils._merge import merge_dicts
[docs]class ChatGeneration(Generation):
"""A single chat generation output."""
text: str = ""
"""*SHOULD NOT BE SET DIRECTLY* The text contents of the output message."""
message: BaseMessage
"""The message output by the chat model."""
# Override type to be ChatGeneration, ignore mypy error as this is intentional
type: Literal["ChatGeneration"] = "ChatGeneration" # type: ignore[assignment]
"""Type is used exclusively for serialization purposes."""
@root_validator
def set_text(cls, values: Dict[str, Any]) -> Dict[str, Any]:
"""Set the text attribute to be the contents of the message."""
try:
values["text"] = values["message"].content
except (KeyError, AttributeError) as e:
raise ValueError("Error while initializing ChatGeneration") from e
return values
[docs] @classmethod
def get_lc_namespace(cls) -> List[str]:
"""Get the namespace of the langchain object."""
return ["langchain", "schema", "output"]
[docs]class ChatGenerationChunk(ChatGeneration):
"""ChatGeneration chunk, which can be concatenated with other
ChatGeneration chunks.
Attributes:
message: The message chunk output by the chat model.
"""
message: BaseMessageChunk
# Override type to be ChatGeneration, ignore mypy error as this is intentional
type: Literal["ChatGenerationChunk"] = "ChatGenerationChunk" # type: ignore[assignment] # noqa: E501
"""Type is used exclusively for serialization purposes."""
[docs] @classmethod
def get_lc_namespace(cls) -> List[str]:
"""Get the namespace of the langchain object."""
return ["langchain", "schema", "output"]
def __add__(self, other: ChatGenerationChunk) -> ChatGenerationChunk:
if isinstance(other, ChatGenerationChunk):
generation_info = merge_dicts(
self.generation_info or {},
other.generation_info or {},
)
return ChatGenerationChunk(
message=self.message + other.message,
generation_info=generation_info or None,
)
else:
raise TypeError(
f"unsupported operand type(s) for +: '{type(self)}' and '{type(other)}'"
)