Create chat_model.py

chat_model.py

@@ -0,0 +1,40 @@
+import os
+import logging
+import asyncio
+from huggingface_hub import hf_hub_download
+from llama_cpp import Llama
+
+logger = logging.getLogger("nexari.chat")
+BASE_DIR = "./models/chat"
+model = None
+
+REPO_ID = "bartowski/Meta-Llama-3.1-8B-Instruct-GGUF"
+FILENAME = "Meta-Llama-3.1-8B-Instruct-Q4_K_M.gguf"
+
+def download_if_needed(local_dir: str):
+    os.makedirs(local_dir, exist_ok=True)
+    local_path = os.path.join(local_dir, FILENAME)
+    if os.path.exists(local_path):
+        logger.info(f"Chat model already present: {local_path}")
+        return local_path
+    logger.info(f"Downloading chat model to {local_dir} ...")
+    path = hf_hub_download(repo_id=REPO_ID, filename=FILENAME, local_dir=local_dir)
+    logger.info(f"Downloaded chat: {path}")
+    return path
+
+def load_model(local_dir: str = None):
+    global model
+    if not local_dir:
+        local_dir = BASE_DIR
+    try:
+        model_path = download_if_needed(local_dir)
+        model = Llama(model_path=model_path, n_ctx=2048, verbose=False)
+        logger.info("Chat model loaded")
+        return model
+    except Exception as e:
+        logger.exception(f"Failed to load chat model: {e}")
+        model = None
+        raise
+
+async def load_model_async():
+    return await asyncio.to_thread(load_model)