Source code for langchain.embeddings.aleph_alpha
from typing import Any, Dict, List, Optional
from pydantic import BaseModel, root_validator
from langchain.embeddings.base import Embeddings
from langchain.utils import get_from_dict_or_env
[docs]class AlephAlphaAsymmetricSemanticEmbedding(BaseModel, Embeddings):
    """
    Wrapper for Aleph Alpha's Asymmetric Embeddings
    AA provides you with an endpoint to embed a document and a query.
    The models were optimized to make the embeddings of documents and
    the query for a document as similar as possible.
    To learn more, check out: https://docs.aleph-alpha.com/docs/tasks/semantic_embed/
    Example:
        .. code-block:: python
            from aleph_alpha import AlephAlphaAsymmetricSemanticEmbedding
            embeddings = AlephAlphaSymmetricSemanticEmbedding()
            document = "This is a content of the document"
            query = "What is the content of the document?"
            doc_result = embeddings.embed_documents([document])
            query_result = embeddings.embed_query(query)
    """
    client: Any  #: :meta private:
    model: Optional[str] = "luminous-base"
    """Model name to use."""
    hosting: Optional[str] = "https://api.aleph-alpha.com"
    """Optional parameter that specifies which datacenters may process the request."""
    normalize: Optional[bool] = True
    """Should returned embeddings be normalized"""
    compress_to_size: Optional[int] = 128
    """Should the returned embeddings come back as an original 5120-dim vector, 
    or should it be compressed to 128-dim."""
    contextual_control_threshold: Optional[int] = None
    """Attention control parameters only apply to those tokens that have 
    explicitly been set in the request."""
    control_log_additive: Optional[bool] = True
    """Apply controls on prompt items by adding the log(control_factor) 
    to attention scores."""
    aleph_alpha_api_key: Optional[str] = None
    """API key for Aleph Alpha API."""
    @root_validator()
    def validate_environment(cls, values: Dict) -> Dict:
        """Validate that api key and python package exists in environment."""
        aleph_alpha_api_key = get_from_dict_or_env(
            values, "aleph_alpha_api_key", "ALEPH_ALPHA_API_KEY"
        )
        try:
            from aleph_alpha_client import Client
        except ImportError:
            raise ValueError(
                "Could not import aleph_alpha_client python package. "
                "Please install it with `pip install aleph_alpha_client`."
            )
        values["client"] = Client(token=aleph_alpha_api_key)
        return values
[docs]    def embed_documents(self, texts: List[str]) -> List[List[float]]:
        """Call out to Aleph Alpha's asymmetric Document endpoint.
        Args:
            texts: The list of texts to embed.
        Returns:
            List of embeddings, one for each text.
        """
        try:
            from aleph_alpha_client import (
                Prompt,
                SemanticEmbeddingRequest,
                SemanticRepresentation,
            )
        except ImportError:
            raise ValueError(
                "Could not import aleph_alpha_client python package. "
                "Please install it with `pip install aleph_alpha_client`."
            )
        document_embeddings = []
        for text in texts:
            document_params = {
                "prompt": Prompt.from_text(text),
                "representation": SemanticRepresentation.Document,
                "compress_to_size": self.compress_to_size,
                "normalize": self.normalize,
                "contextual_control_threshold": self.contextual_control_threshold,
                "control_log_additive": self.control_log_additive,
            }
            document_request = SemanticEmbeddingRequest(**document_params)
            document_response = self.client.semantic_embed(
                request=document_request, model=self.model
            )
            document_embeddings.append(document_response.embedding)
        return document_embeddings
[docs]    def embed_query(self, text: str) -> List[float]:
        """Call out to Aleph Alpha's asymmetric, query embedding endpoint
        Args:
            text: The text to embed.
        Returns:
            Embeddings for the text.
        """
        try:
            from aleph_alpha_client import (
                Prompt,
                SemanticEmbeddingRequest,
                SemanticRepresentation,
            )
        except ImportError:
            raise ValueError(
                "Could not import aleph_alpha_client python package. "
                "Please install it with `pip install aleph_alpha_client`."
            )
        symmetric_params = {
            "prompt": Prompt.from_text(text),
            "representation": SemanticRepresentation.Query,
            "compress_to_size": self.compress_to_size,
            "normalize": self.normalize,
            "contextual_control_threshold": self.contextual_control_threshold,
            "control_log_additive": self.control_log_additive,
        }
        symmetric_request = SemanticEmbeddingRequest(**symmetric_params)
        symmetric_response = self.client.semantic_embed(
            request=symmetric_request, model=self.model
        )
        return symmetric_response.embedding
[docs]class AlephAlphaSymmetricSemanticEmbedding(AlephAlphaAsymmetricSemanticEmbedding):
    """The symmetric version of the Aleph Alpha's semantic embeddings.
    The main difference is that here, both the documents and
    queries are embedded with a SemanticRepresentation.Symmetric
    Example:
        .. code-block:: python
            from aleph_alpha import AlephAlphaSymmetricSemanticEmbedding
            embeddings = AlephAlphaAsymmetricSemanticEmbedding()
            text = "This is a test text"
            doc_result = embeddings.embed_documents([text])
            query_result = embeddings.embed_query(text)
    """
    def _embed(self, text: str) -> List[float]:
        try:
            from aleph_alpha_client import (
                Prompt,
                SemanticEmbeddingRequest,
                SemanticRepresentation,
            )
        except ImportError:
            raise ValueError(
                "Could not import aleph_alpha_client python package. "
                "Please install it with `pip install aleph_alpha_client`."
            )
        query_params = {
            "prompt": Prompt.from_text(text),
            "representation": SemanticRepresentation.Symmetric,
            "compress_to_size": self.compress_to_size,
            "normalize": self.normalize,
            "contextual_control_threshold": self.contextual_control_threshold,
            "control_log_additive": self.control_log_additive,
        }
        query_request = SemanticEmbeddingRequest(**query_params)
        query_response = self.client.semantic_embed(
            request=query_request, model=self.model
        )
        return query_response.embedding
[docs]    def embed_documents(self, texts: List[str]) -> List[List[float]]:
        """Call out to Aleph Alpha's Document endpoint.
        Args:
            texts: The list of texts to embed.
        Returns:
            List of embeddings, one for each text.
        """
        document_embeddings = []
        for text in texts:
            document_embeddings.append(self._embed(text))
        return document_embeddings
[docs]    def embed_query(self, text: str) -> List[float]:
        """Call out to Aleph Alpha's asymmetric, query embedding endpoint
        Args:
            text: The text to embed.
        Returns:
            Embeddings for the text.
        """
        return self._embed(text)