quivr/backend/llm/brainpicking.py
Stan Girard 8ed8a2c9ef chore: 🤖 docs
added docs
2023-06-20 08:56:17 +02:00

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Python

import os # A module to interact with the OS
from typing import Any, Dict, List # For type hinting
# Importing various modules and classes from a custom library 'langchain' likely used for natural language processing
from langchain.chains import ConversationalRetrievalChain, LLMChain
from langchain.chains.question_answering import load_qa_chain
from langchain.chains.router.llm_router import (LLMRouterChain,
RouterOutputParser)
from langchain.chains.router.multi_prompt_prompt import \
MULTI_PROMPT_ROUTER_TEMPLATE
from langchain.chat_models import ChatOpenAI, ChatVertexAI
from langchain.chat_models.anthropic import ChatAnthropic
from langchain.docstore.document import Document
from langchain.embeddings.openai import OpenAIEmbeddings
from langchain.llms import OpenAI, VertexAI
from langchain.memory import ConversationBufferMemory
from langchain.vectorstores import SupabaseVectorStore
from llm.prompt import LANGUAGE_PROMPT
from llm.prompt.CONDENSE_PROMPT import CONDENSE_QUESTION_PROMPT
from models.chats import \
ChatMessage # Importing a custom ChatMessage class for handling chat messages
from models.settings import \
BrainSettings # Importing settings related to the 'brain'
from pydantic import (BaseModel, # For data validation and settings management
BaseSettings)
from supabase import (Client, # For interacting with Supabase database
create_client)
from vectorstore.supabase import \
CustomSupabaseVectorStore # Custom class for handling vector storage with Supabase
class AnswerConversationBufferMemory(ConversationBufferMemory):
"""
This class is a specialized version of ConversationBufferMemory.
It overrides the save_context method to save the response using the 'answer' key in the outputs.
Reference to some issue comment is given in the docstring.
"""
def save_context(self, inputs: Dict[str, Any], outputs: Dict[str, str]) -> None:
# Overriding the save_context method of the parent class
return super(AnswerConversationBufferMemory, self).save_context(
inputs, {'response': outputs['answer']})
def get_chat_history(inputs) -> str:
"""
Function to concatenate chat history into a single string.
:param inputs: List of tuples containing human and AI messages.
:return: concatenated string of chat history
"""
res = []
for human, ai in inputs:
res.append(f"{human}:{ai}\n")
return "\n".join(res)
class BrainPicking(BaseModel):
"""
Main class for the Brain Picking functionality.
It allows to initialize a Chat model, generate questions and retrieve answers using ConversationalRetrievalChain.
"""
# Default class attributes
llm_name: str = "gpt-3.5-turbo"
settings = BrainSettings()
embeddings: OpenAIEmbeddings = None
supabase_client: Client = None
vector_store: CustomSupabaseVectorStore = None
llm: ChatOpenAI = None
question_generator: LLMChain = None
doc_chain: ConversationalRetrievalChain = None
class Config:
# Allowing arbitrary types for class validation
arbitrary_types_allowed = True
def init(self, model: str, user_id: str) -> "BrainPicking":
"""
Initialize the BrainPicking class by setting embeddings, supabase client, vector store, language model and chains.
:param model: Language model name to be used.
:param user_id: The user id to be used for CustomSupabaseVectorStore.
:return: BrainPicking instance
"""
self.embeddings = OpenAIEmbeddings(openai_api_key=self.settings.openai_api_key)
self.supabase_client = create_client(self.settings.supabase_url, self.settings.supabase_service_key)
self.vector_store = CustomSupabaseVectorStore(
self.supabase_client, self.embeddings, table_name="vectors", user_id=user_id)
self.llm = ChatOpenAI(temperature=0, model_name=model)
self.question_generator = LLMChain(llm=self.llm, prompt=CONDENSE_QUESTION_PROMPT)
self.doc_chain = load_qa_chain(self.llm, chain_type="stuff")
return self
def _get_qa(self, chat_message: ChatMessage, user_openai_api_key) -> ConversationalRetrievalChain:
"""
Retrieves a QA chain for the given chat message and API key.
:param chat_message: The chat message containing history.
:param user_openai_api_key: The OpenAI API key to be used.
:return: ConversationalRetrievalChain instance
"""
# If user provided an API key, update the settings
if user_openai_api_key is not None and user_openai_api_key != "":
self.settings.openai_api_key = user_openai_api_key
# Initialize and return a ConversationalRetrievalChain
qa = ConversationalRetrievalChain(
retriever=self.vector_store.as_retriever(),
max_tokens_limit=chat_message.max_tokens, question_generator=self.question_generator,
combine_docs_chain=self.doc_chain, get_chat_history=get_chat_history)
return qa
def generate_answer(self, chat_message: ChatMessage, user_openai_api_key) -> str:
"""
Generate an answer to a given chat message by interacting with the language model.
:param chat_message: The chat message containing history.
:param user_openai_api_key: The OpenAI API key to be used.
:return: The generated answer.
"""
transformed_history = []
# Get the QA chain
qa = self._get_qa(chat_message, user_openai_api_key)
# Transform the chat history into a list of tuples
for i in range(0, len(chat_message.history) - 1, 2):
user_message = chat_message.history[i][1]
assistant_message = chat_message.history[i + 1][1]
transformed_history.append((user_message, assistant_message))
# Generate the model response using the QA chain
model_response = qa({"question": chat_message.question, "chat_history": transformed_history})
answer = model_response['answer']
return answer