from typing import Any, List, Optional
from langchain_core.embeddings import Embeddings
from pydantic import BaseModel, ConfigDict, Field, model_validator
from typing_extensions import Self
[docs]
class LlamaCppEmbeddings(BaseModel, Embeddings):
"""llama.cpp embedding models.
To use, you should have the llama-cpp-python library installed, and provide the
path to the Llama model as a named parameter to the constructor.
Check out: https://github.com/abetlen/llama-cpp-python
Example:
.. code-block:: python
from langchain_community.embeddings import LlamaCppEmbeddings
llama = LlamaCppEmbeddings(model_path="/path/to/model.bin")
"""
client: Any = None #: :meta private:
model_path: str
n_ctx: int = Field(512, alias="n_ctx")
"""Token context window."""
n_parts: int = Field(-1, alias="n_parts")
"""Number of parts to split the model into.
If -1, the number of parts is automatically determined."""
seed: int = Field(-1, alias="seed")
"""Seed. If -1, a random seed is used."""
f16_kv: bool = Field(False, alias="f16_kv")
"""Use half-precision for key/value cache."""
logits_all: bool = Field(False, alias="logits_all")
"""Return logits for all tokens, not just the last token."""
vocab_only: bool = Field(False, alias="vocab_only")
"""Only load the vocabulary, no weights."""
use_mlock: bool = Field(False, alias="use_mlock")
"""Force system to keep model in RAM."""
n_threads: Optional[int] = Field(None, alias="n_threads")
"""Number of threads to use. If None, the number
of threads is automatically determined."""
n_batch: Optional[int] = Field(512, alias="n_batch")
"""Number of tokens to process in parallel.
Should be a number between 1 and n_ctx."""
n_gpu_layers: Optional[int] = Field(None, alias="n_gpu_layers")
"""Number of layers to be loaded into gpu memory. Default None."""
verbose: bool = Field(True, alias="verbose")
"""Print verbose output to stderr."""
device: Optional[str] = Field(None, alias="device")
"""Device type to use and pass to the model"""
model_config = ConfigDict(
extra="forbid",
protected_namespaces=(),
)
@model_validator(mode="after")
def validate_environment(self) -> Self:
"""Validate that llama-cpp-python library is installed."""
model_path = self.model_path
model_param_names = [
"n_ctx",
"n_parts",
"seed",
"f16_kv",
"logits_all",
"vocab_only",
"use_mlock",
"n_threads",
"n_batch",
"verbose",
"device",
]
model_params = {k: getattr(self, k) for k in model_param_names}
# For backwards compatibility, only include if non-null.
if self.n_gpu_layers is not None:
model_params["n_gpu_layers"] = self.n_gpu_layers
try:
from llama_cpp import Llama
self.client = Llama(model_path, embedding=True, **model_params)
except ImportError:
raise ImportError(
"Could not import llama-cpp-python library. "
"Please install the llama-cpp-python library to "
"use this embedding model: pip install llama-cpp-python"
)
except Exception as e:
raise ValueError(
f"Could not load Llama model from path: {model_path}. "
f"Received error {e}"
)
return self
[docs]
def embed_documents(self, texts: List[str]) -> List[List[float]]:
"""Embed a list of documents using the Llama model.
Args:
texts: The list of texts to embed.
Returns:
List of embeddings, one for each text.
"""
embeddings = self.client.create_embedding(texts)
return [list(map(float, e["embedding"])) for e in embeddings["data"]]
[docs]
def embed_query(self, text: str) -> List[float]:
"""Embed a query using the Llama model.
Args:
text: The text to embed.
Returns:
Embeddings for the text.
"""
embedding = self.client.embed(text)
return list(map(float, embedding))
