Scrapegraph-ai/scrapegraphai/nodes/rag_node.py
2024-08-27 16:54:57 +02:00

266 lines
11 KiB
Python

"""
RAGNode Module
"""
import os
import sys
from typing import List, Optional
from langchain.docstore.document import Document
from langchain.retrievers import ContextualCompressionRetriever
from langchain.retrievers.document_compressors import (
DocumentCompressorPipeline,
EmbeddingsFilter,
)
from langchain_community.document_transformers import EmbeddingsRedundantFilter
from langchain_community.vectorstores import FAISS
from langchain_community.chat_models import ChatOllama
from langchain_aws import BedrockEmbeddings, ChatBedrock
from langchain_community.embeddings import OllamaEmbeddings
from langchain_google_genai import GoogleGenerativeAIEmbeddings, ChatGoogleGenerativeAI
from langchain_openai import AzureOpenAIEmbeddings, OpenAIEmbeddings, ChatOpenAI, AzureChatOpenAI
from ..utils.logging import get_logger
from .base_node import BaseNode
from ..helpers import models_tokens
from ..models import DeepSeek
optional_modules = {"langchain_anthropic", "langchain_fireworks", "langchain_groq", "langchain_google_vertexai"}
class RAGNode(BaseNode):
"""
A node responsible for compressing the input tokens and storing the document
in a vector database for retrieval. Relevant chunks are stored in the state.
It allows scraping of big documents without exceeding the token limit of the language model.
Attributes:
llm_model: An instance of a language model client, configured for generating answers.
embedder_model: An instance of an embedding model client, configured for generating embeddings.
verbose (bool): A flag indicating whether to show print statements during execution.
Args:
input (str): Boolean expression defining the input keys needed from the state.
output (List[str]): List of output keys to be updated in the state.
node_config (dict): Additional configuration for the node.
node_name (str): The unique identifier name for the node, defaulting to "Parse".
"""
def __init__(
self,
input: str,
output: List[str],
node_config: Optional[dict] = None,
node_name: str = "RAG",
):
super().__init__(node_name, "node", input, output, 2, node_config)
self.llm_model = node_config["llm_model"]
self.embedder_model = node_config.get("embedder_model", None)
self.verbose = (
False if node_config is None else node_config.get("verbose", False)
)
self.cache_path = node_config.get("cache_path", False)
def execute(self, state: dict) -> dict:
"""
Executes the node's logic to implement RAG (Retrieval-Augmented Generation).
The method updates the state with relevant chunks of the document.
Args:
state (dict): The current state of the graph. The input keys will be used to fetch the
correct data from the state.
Returns:
dict: The updated state with the output key containing the relevant chunks of the document.
Raises:
KeyError: If the input keys are not found in the state, indicating that the
necessary information for compressing the content is missing.
"""
self.logger.info(f"--- Executing {self.node_name} Node ---")
input_keys = self.get_input_keys(state)
input_data = [state[key] for key in input_keys]
user_prompt = input_data[0]
doc = input_data[1]
chunked_docs = []
for i, chunk in enumerate(doc):
doc = Document(
page_content=chunk,
metadata={
"chunk": i + 1,
},
)
chunked_docs.append(doc)
self.logger.info("--- (updated chunks metadata) ---")
if self.embedder_model is not None:
embeddings = self.embedder_model
elif 'embeddings' in self.node_config:
try:
embeddings = self._create_embedder(self.node_config['embedder_config'])
except Exception:
try:
embeddings = self._create_default_embedder()
self.embedder_model = embeddings
except ValueError:
embeddings = self.llm_model
self.embedder_model = self.llm_model
else:
embeddings = self.llm_model
self.embedder_model = self.llm_model
folder_name = self.node_config.get("cache_path", "cache")
if self.node_config.get("cache_path", False) and not os.path.exists(folder_name):
index = FAISS.from_documents(chunked_docs, embeddings)
os.makedirs(folder_name)
index.save_local(folder_name)
self.logger.info("--- (indexes saved to cache) ---")
elif self.node_config.get("cache_path", False) and os.path.exists(folder_name):
index = FAISS.load_local(folder_path=folder_name,
embeddings=embeddings,
allow_dangerous_deserialization=True)
self.logger.info("--- (indexes loaded from cache) ---")
else:
index = FAISS.from_documents(chunked_docs, embeddings)
retriever = index.as_retriever()
redundant_filter = EmbeddingsRedundantFilter(embeddings=embeddings)
# similarity_threshold could be set, now k=20
relevant_filter = EmbeddingsFilter(embeddings=embeddings)
pipeline_compressor = DocumentCompressorPipeline(
transformers=[redundant_filter, relevant_filter]
)
compression_retriever = ContextualCompressionRetriever(
base_compressor=pipeline_compressor, base_retriever=retriever
)
compressed_docs = compression_retriever.invoke(user_prompt)
self.logger.info("--- (tokens compressed and vector stored) ---")
state.update({self.output[0]: compressed_docs})
return state
def _create_default_embedder(self, llm_config=None) -> object:
"""
Create an embedding model instance based on the chosen llm model.
Returns:
object: An instance of the embedding model client.
Raises:
ValueError: If the model is not supported.
"""
if isinstance(self.llm_model, ChatGoogleGenerativeAI):
return GoogleGenerativeAIEmbeddings(
google_api_key=llm_config["api_key"], model="models/embedding-001"
)
if isinstance(self.llm_model, ChatOpenAI):
return OpenAIEmbeddings(api_key=self.llm_model.openai_api_key,
base_url=self.llm_model.openai_api_base)
elif isinstance(self.llm_model, DeepSeek):
return OpenAIEmbeddings(api_key=self.llm_model.openai_api_key)
elif isinstance(self.llm_model, AzureOpenAIEmbeddings):
return self.llm_model
elif isinstance(self.llm_model, AzureChatOpenAI):
return AzureOpenAIEmbeddings()
elif isinstance(self.llm_model, ChatOllama):
# unwrap the kwargs from the model whihc is a dict
params = self.llm_model._lc_kwargs
# remove streaming and temperature
params.pop("streaming", None)
params.pop("temperature", None)
return OllamaEmbeddings(**params)
elif isinstance(self.llm_model, ChatBedrock):
return BedrockEmbeddings(client=None, model_id=self.llm_model.model_id)
elif all(key in sys.modules for key in optional_modules):
if isinstance(self.llm_model, ChatFireworks):
return FireworksEmbeddings(model=self.llm_model.model_name)
if isinstance(self.llm_model, ChatNVIDIA):
return NVIDIAEmbeddings(model=self.llm_model.model_name)
if isinstance(self.llm_model, ChatHuggingFace):
return HuggingFaceEmbeddings(model=self.llm_model.model)
if isinstance(self.llm_model, ChatVertexAI):
return VertexAIEmbeddings()
else:
raise ValueError("Embedding Model missing or not supported")
def _create_embedder(self, embedder_config: dict) -> object:
"""
Create an embedding model instance based on the configuration provided.
Args:
embedder_config (dict): Configuration parameters for the embedding model.
Returns:
object: An instance of the embedding model client.
Raises:
KeyError: If the model is not supported.
"""
embedder_params = {**embedder_config}
if "model_instance" in embedder_config:
return embedder_params["model_instance"]
if "openai" in embedder_params["model"]:
return OpenAIEmbeddings(api_key=embedder_params["api_key"])
if "azure" in embedder_params["model"]:
return AzureOpenAIEmbeddings()
if "ollama" in embedder_params["model"]:
embedder_params["model"] = "/".join(embedder_params["model"].split("/")[1:])
try:
models_tokens["ollama"][embedder_params["model"]]
except KeyError as exc:
raise KeyError("Model not supported") from exc
return OllamaEmbeddings(**embedder_params)
if "gemini" in embedder_params["model"]:
try:
models_tokens["gemini"][embedder_params["model"]]
except KeyError as exc:
raise KeyError("Model not supported") from exc
return GoogleGenerativeAIEmbeddings(model=embedder_params["model"])
if "bedrock" in embedder_params["model"]:
embedder_params["model"] = embedder_params["model"].split("/")[-1]
client = embedder_params.get("client", None)
try:
models_tokens["bedrock"][embedder_params["model"]]
except KeyError as exc:
raise KeyError("Model not supported") from exc
return BedrockEmbeddings(client=client, model_id=embedder_params["model"])
if all(key in sys.modules for key in optional_modules):
if "hugging_face" in embedder_params["model"]:
embedder_params["model"] = "/".join(embedder_params["model"].split("/")[1:])
try:
models_tokens["hugging_face"][embedder_params["model"]]
except KeyError as exc:
raise KeyError("Model not supported") from exc
return HuggingFaceEmbeddings(model=embedder_params["model"])
if "fireworks" in embedder_params["model"]:
embedder_params["model"] = "/".join(embedder_params["model"].split("/")[1:])
try:
models_tokens["fireworks"][embedder_params["model"]]
except KeyError as exc:
raise KeyError("Model not supported") from exc
return FireworksEmbeddings(model=embedder_params["model"])
if "nvidia" in embedder_params["model"]:
embedder_params["model"] = "/".join(embedder_params["model"].split("/")[1:])
try:
models_tokens["nvidia"][embedder_params["model"]]
except KeyError as exc:
raise KeyError("Model not supported") from exc
return NVIDIAEmbeddings(model=embedder_params["model"],
nvidia_api_key=embedder_params["api_key"])
raise ValueError("Model provided by the configuration not supported")