from typing import TypedDict, Annotated from tool import (add, substract, multiply, divide, DuckDuckGoSearchTool, TavilySearchTool, combined_web_search, WikipediaSearchTool, ArxivSearchTool, PubmedSearchTool, save_and_read_file, download_file_from_url, extract_text_from_image, analyze_csv_file, analyze_excel_file, extract_video_id, get_youtube_transcript) import os from os import getenv from langgraph.graph.message import add_messages from langchain_core.messages import AnyMessage, SystemMessage, HumanMessage, AIMessage from langgraph.graph import StateGraph, START, END, MessagesState from langgraph.prebuilt import ToolNode, tools_condition from langchain_huggingface import HuggingFaceEndpoint, ChatHuggingFace, HuggingFaceEmbeddings from langchain_google_genai import ChatGoogleGenerativeAI from langchain_groq import ChatGroq from langchain_community.vectorstores import SupabaseVectorStore from langchain.tools.retriever import create_retriever_tool from langchain_core.rate_limiters import InMemoryRateLimiter from supabase.client import Client, create_client import time HUGGINGFACEHUB_API_TOKEN = getenv("HUGGINGFACEHUB_API_TOKEN") SUPABASE_URL = os.environ.get("SUPABASE_URL") SUPABASE_SERVICE_ROLE_KEY = os.environ.get("SUPABASE_SERVICE_ROLE_KEY") TAVILY_API_KEY = os.environ.get("TAVILY_API_KEY") GROQ_API_KEY = os.environ.get("GROQ_API_KEY") # load the system prompt from the file with open("prompt.txt", "r", encoding="utf-8") as f: system_prompt = f.read() # System message sys_msg = SystemMessage(content=system_prompt) # build a retriever embeddings = HuggingFaceEmbeddings(model_name="sentence-transformers/all-MiniLM-L6-v2") # dim=384 supabase: Client = create_client( SUPABASE_URL, SUPABASE_SERVICE_ROLE_KEY) vector_store = SupabaseVectorStore( client = supabase, embedding = embeddings, table_name = "documents", query_name = "match_documents_langchain",) retriever_tool = create_retriever_tool( retriever=vector_store.as_retriever(), name="Question Search", description="A tool to retrieve similar questions from a vector store.",) # Loading the assistant chat = ChatGoogleGenerativeAI(model="gemini-2.0-flash", temperature=0) tools = [add, substract, multiply, divide, DuckDuckGoSearchTool, TavilySearchTool, combined_web_search, WikipediaSearchTool, ArxivSearchTool, PubmedSearchTool, save_and_read_file, download_file_from_url, extract_text_from_image, analyze_csv_file, analyze_excel_file, extract_video_id, get_youtube_transcript ] chat_with_tools = chat.bind_tools(tools) def simple_graph(): def assistant(state: MessagesState): """Assistant node""" return {"messages": [chat_with_tools.invoke([sys_msg] + state["messages"])]} def retriever(state: MessagesState): """Retriever node""" similar_question = vector_store.similarity_search(state["messages"][0].content) example_msg = HumanMessage( content=f"Here I provide a similar question and answer for reference: \n\n{similar_question[0].page_content}", ) return {"messages": [sys_msg] + state["messages"] + [example_msg]} # Build graph / nodes builder = StateGraph(MessagesState) builder.add_node("retriever", retriever) builder.add_node("assistant", assistant) builder.add_node("tools", ToolNode(tools)) # Logic / edges builder.add_edge(START, "retriever") builder.add_edge("retriever", "assistant") builder.add_conditional_edges( "assistant", tools_condition, ) builder.add_edge("tools", "assistant") graph = builder.compile() return graph