cohere_rerank.py — langchain Source File

Source Code

from __future__ import annotations

from collections.abc import Sequence
from copy import deepcopy
from typing import Any

from langchain_core._api.deprecation import deprecated
from langchain_core.callbacks import Callbacks
from langchain_core.documents import BaseDocumentCompressor, Document
from langchain_core.utils import get_from_dict_or_env
from pydantic import ConfigDict, model_validator
from typing_extensions import override


@deprecated(
    since="0.0.30",
    removal="1.0",
    alternative_import="langchain_cohere.CohereRerank",
)
class CohereRerank(BaseDocumentCompressor):
    """Document compressor that uses `Cohere Rerank API`."""

    client: Any = None
    """Cohere client to use for compressing documents."""
    top_n: int | None = 3
    """Number of documents to return."""
    model: str = "rerank-english-v2.0"
    """Model to use for reranking."""
    cohere_api_key: str | None = None
    """Cohere API key. Must be specified directly or via environment variable
        COHERE_API_KEY."""
    user_agent: str = "langchain"
    """Identifier for the application making the request."""

    model_config = ConfigDict(
        arbitrary_types_allowed=True,
        extra="forbid",
    )

    @model_validator(mode="before")
    @classmethod
    def validate_environment(cls, values: dict) -> Any:
        """Validate that api key and python package exists in environment."""
        if not values.get("client"):
            try:
                import cohere
            except ImportError as e:
                msg = (
                    "Could not import cohere python package. "
                    "Please install it with `pip install cohere`."
                )
                raise ImportError(msg) from e
            cohere_api_key = get_from_dict_or_env(
                values,
                "cohere_api_key",
                "COHERE_API_KEY",
            )
            client_name = values.get("user_agent", "langchain")
            values["client"] = cohere.Client(cohere_api_key, client_name=client_name)
        return values
// ... (65 more lines)