Create FAISS index using omdena qna dataset (#4)

- Create FAISS index using omdena qna dataset (b38f7550122233810db9ef6a3aa08a90a1959fdd)


Co-authored-by: Anand <[email protected]>

create_faiss_index.py

@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+"""create_faiss_index.py
+"""
+
+import pandas as pd
+import numpy as np
+import faiss
+from sentence_transformers import InputExample, SentenceTransformer
+
+DATA_FILE_PATH = "omdena_qna_dataset/omdena_faq_training_data.csv"
+TRANSFORMER_MODEL_NAME = "all-distilroberta-v1"
+CACHE_DIR_PATH = "../working/cache/"
+MODEL_SAVE_PATH = "all-distilroberta-v1-model.pkl"
+FAISS_INDEX_FILE_PATH = "index.faiss"
+
+def load_data(file_path):
+    qna_dataset = pd.read_csv(file_path)
+    qna_dataset["id"] = qna_dataset.index
+    return qna_dataset.dropna(subset=['Answers']).copy()
+
+def create_input_examples(qna_dataset):
+    qna_dataset['QNA'] = qna_dataset.apply(lambda row: f"Question: {row['Questions']}, Answer: {row['Answers']}", axis=1)
+    return qna_dataset.apply(lambda x: InputExample(texts=[x["QNA"]]), axis=1).tolist()
+
+def load_transformer_model(model_name, cache_folder):
+    transformer_model = SentenceTransformer(model_name, cache_folder=cache_folder)
+    return transformer_model
+
+def save_transformer_model(transformer_model, model_file):
+    transformer_model.save(model_file)
+    
+def create_faiss_index(transformer_model, qna_dataset):
+    faiss_embeddings = transformer_model.encode(qna_dataset.Answers.values.tolist())
+    qna_dataset_indexed = qna_dataset.set_index(["id"], drop=False)
+    id_index_array = np.array(qna_dataset_indexed.id.values).flatten().astype("int")
+    normalized_embeddings = faiss_embeddings.copy()
+    faiss.normalize_L2(normalized_embeddings)
+    faiss_index = faiss.IndexIDMap(faiss.IndexFlatIP(len(faiss_embeddings[0])))
+    faiss_index.add_with_ids(normalized_embeddings, id_index_array)
+    return faiss_index
+
+def save_faiss_index(faiss_index, filename):
+    faiss.write_index(faiss_index, filename)
+
+def load_faiss_index(filename):
+    return faiss.read_index(filename)
+
+def main():
+    qna_dataset = load_data(DATA_FILE_PATH)
+    input_examples = create_input_examples(qna_dataset)
+    transformer_model = load_transformer_model(TRANSFORMER_MODEL_NAME, CACHE_DIR_PATH)
+    save_transformer_model(transformer_model, MODEL_SAVE_PATH)
+    faiss_index = create_faiss_index(transformer_model, qna_dataset)
+    save_faiss_index(faiss_index, FAISS_INDEX_FILE_PATH)
+    faiss_index = load_faiss_index(FAISS_INDEX_FILE_PATH)
+
+if __name__ == "__main__":
+    main()