Review-RAG / src /build_vectorstore.py
HariHaran9597
Initial commit
1d70196
import pandas as pd
import faiss
import pickle
import os
import argparse
from sentence_transformers import SentenceTransformer
def main():
parser = argparse.ArgumentParser(description="Embed labeled reviews into FAISS vectorstore.")
parser.add_argument('--input_csv', type=str, default='data/processed/amazon_labeled_reviews.csv', help='CSV with texts and predicted_aspects')
parser.add_argument('--out_dir', type=str, default='vectorstore', help='Directory to output FAISS index')
parser.add_argument('--text_column', type=str, default='reviewDocument', help='Name of the column containing the review text')
parser.add_argument('--model_name', type=str, default='all-MiniLM-L6-v2', help='Sentence-transformers model')
args = parser.parse_args()
if not os.path.exists(args.input_csv):
print(f"Error: {args.input_csv} not found. Please run src/prepare_amazon_data.py first.")
return
print(f"Loading data from {args.input_csv}...")
df = pd.read_csv(args.input_csv)
if args.text_column not in df.columns:
print(f"Error: Column {args.text_column} not found in {args.input_csv}.")
print(f"Available columns: {df.columns.tolist()}")
return
# Filter out empty texts
df = df[df[args.text_column].notna() & (df[args.text_column] != '')]
texts = df[args.text_column].tolist()
print(f"Loading embedding model: {args.model_name}...")
embedder = SentenceTransformer(args.model_name)
print(f"Encoding {len(texts)} reviews into dense vectors...")
# encode handles batching automatically
embeddings = embedder.encode(texts, show_progress_bar=True, convert_to_numpy=True)
# Initialize FAISS Index (L2 normalized Flat Inner Product = Cosine Similarity)
dimension = embeddings.shape[1]
index = faiss.IndexFlatIP(dimension)
# Normalize before adding to FAISS for cosine similarity
print("Normalizing vectors and adding to FAISS index...")
faiss.normalize_L2(embeddings)
index.add(embeddings)
os.makedirs(args.out_dir, exist_ok=True)
# Save FAISS index
index_path = os.path.join(args.out_dir, 'reviews.index')
faiss.write_index(index, index_path)
# Save the dataframe mapping (so we can retrieve the actual text + labels later)
df_path = os.path.join(args.out_dir, 'reviews_metadata.pkl')
with open(df_path, 'wb') as f:
pickle.dump(df, f)
print(f"\nSuccessfully embedded {len(texts)} reviews and saved to '{args.out_dir}'!")
if __name__ == "__main__":
main()