chore: make ragas as extra requirement

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "leaf-eval-tools"
-version = "0.1.0"
+version = "0.1.1"
 description = "A project that provides eval tools for leaf-playground based projects"
 authors = [
     "The LEAF team (past and future) with the help of all our contributors <leaf@shanda.com>",
@@ -17,6 +17,9 @@ datasets = "^2.15.0"
 ragas = "^0.1.1"
 leaf_ai_backends = "^0.1.0"
 
+[tool.poetry.extras]
+ragas = ["ragas"]
+
 [tool.black]
 line-length = 119
 skip-magic-trailing-comma = true

src/leaf_eval_tools/__init__.py

@@ -0,0 +1 @@
+__version__ = "0.1.1"

src/leaf_eval_tools/ragas_eval_worker.py

@@ -1,5 +1,10 @@
 from typing import Any, Dict, Literal, List, Optional, Union
 
+try:
+    import ragas
+except ImportError:
+    raise ImportError("ragas not installed, please running `pip install leaf-eval-tools[ragas]` to enable ragas.")
+
 from datasets import Dataset
 from ragas import evaluate
 from ragas.evaluation import Result