feat: add server-side script to rebuild FAISS index for deployment environments

rebuild_index_server.py

@@ -0,0 +1,59 @@
+"""
+SERVER-SIDE rebuild script (Linux / Azure App Service).
+Run this once on the deployed server to rebuild the FAISS index with all-mpnet-base-v2.
+
+Usage:
+    cd /home/user/app
+    python rebuild_index_server.py
+"""
+import os
+os.environ["OMP_NUM_THREADS"] = "1"
+os.environ["MKL_NUM_THREADS"] = "1"
+os.environ["KMP_DUPLICATE_LIB_OK"] = "TRUE"
+
+import sys
+sys.path.insert(0, "/home/user/app")
+
+import numpy as np
+import pandas as pd
+import faiss
+from pathlib import Path
+from sentence_transformers import SentenceTransformer
+
+MODEL_NAME   = "all-mpnet-base-v2"
+MODELS_DIR   = Path("/home/user/app/models")
+PARQUET_PATH = MODELS_DIR / "metadata.parquet"
+INDEX_PATH   = MODELS_DIR / "faiss_index.bin"
+EMBED_PATH   = MODELS_DIR / "project_embeddings.npy"
+
+print(f"[SERVER REBUILD] Model: {MODEL_NAME}")
+model = SentenceTransformer(MODEL_NAME)
+dim   = model.get_sentence_embedding_dimension()
+print(f"[SERVER REBUILD] Embedding dim: {dim}")
+
+df = pd.read_parquet(PARQUET_PATH)
+print(f"[SERVER REBUILD] Loaded {len(df)} projects")
+
+def build_text(row):
+    return f"{row.get('project_title','') or ''}. {row.get('abstract','') or ''}. {row.get('description','') or ''}".strip()
+
+texts = df.apply(build_text, axis=1).tolist()
+
+print("[SERVER REBUILD] Generating embeddings...")
+embeddings = model.encode(
+    texts,
+    convert_to_numpy=True,
+    normalize_embeddings=True,
+    show_progress_bar=True,
+    batch_size=8
+).astype("float32")
+
+print(f"[SERVER REBUILD] Embeddings shape: {embeddings.shape}")
+np.save(str(EMBED_PATH), embeddings)
+
+index = faiss.IndexFlatIP(dim)
+index.add(embeddings)
+faiss.write_index(index, str(INDEX_PATH))
+
+print(f"[SERVER REBUILD] Done! Index: {index.ntotal} vectors @ {dim}-dim")
+print("[SERVER REBUILD] Restart the app process to reload the index.")