Build a RAG Knowledge Chatbot with OpenAI, Google Drive, and Supabase

🚀 Build Your Own Knowledge Chatbot Using Google Drive

Create a smart chatbot that answers questions using your Google Drive PDFs—perfect for support, internal docs, education, or research.

🛠️ Quick Setup Guide**

Step 1: Prerequisites

• n8n instance (cloud or self-hosted)
• Google Drive account (with PDFs)
• Supabase account (vector database)
• OpenAI API key
• PostgreSQL database (for chat memory) else remove the node

Step 2: Supabase Setup

• Create supabase account (its free)
• Create a project
• Copy the sql and paste it in supabase sql editor

-- Enable the pgvector extension to work with embedding vectors
create extension vector;

-- Create a table to store your documents
create table documents (
  id bigserial primary key,
  content text, -- corresponds to Document.pageContent
  metadata jsonb, -- corresponds to Document.metadata
  embedding vector(1536) -- 1536 works for OpenAI embeddings, change if needed
);

-- Create a function to search for documents
create function match_documents (
  query_embedding vector(1536),
  match_count int default null,
  filter jsonb DEFAULT '{}'
) returns table (
  id bigint,
  content text,
  metadata jsonb,
  similarity float
)
language plpgsql
as $$
#variable_conflict use_column
begin
  return query
  select
    id,
    content,
    metadata,
    1 - (documents.embedding <=> query_embedding) as similarity
  from documents
  where metadata @> filter
  order by documents.embedding <=> query_embedding
  limit match_count;
end;
$$;

Step 3: Import & Configure n8n Workflow

• Import this template into n8n
• Add credentials:
  • OpenAI API key
  • Google Drive OAuth2
  • Supabase URL & service key
  • PostgreSQL connection
• Set your Google Drive folder ID in triggers

Step 4: Test & Use

• Add a PDF to your Drive folder → check Supabase for new entries
• Start the workflow and chat → ask questions about your documents. "What can you help me with?"
• Multi-turn chat → context is maintained per user

⚡ Features

• Auto-syncs new/updated PDFs from Google Drive
• Extracts, chunks, and vectorizes text
• Finds relevant info and answers questions
• Maintains chat history per user

📝 Troubleshooting

• Check folder permissions & IDs if no docs found
• Verify API keys & Supabase setup for errors
• Ensure PostgreSQL is connected for chat memory

Tags: RAG, Chatbot, Google Drive, Supabase, OpenAI, n8n
Setup Time: ~20 minutes