feat(rag): Support rag retriever evaluation (#1291)

dbgpt/rag/operators/embedding.py

@@ -1,16 +1,17 @@
 """Embedding retriever operator."""
 
 from functools import reduce
-from typing import Any, Optional
+from typing import List, Optional, Union
 
 from dbgpt.core.interface.operators.retriever import RetrieverOperator
+from dbgpt.rag.chunk import Chunk
 from dbgpt.rag.retriever.embedding import EmbeddingRetriever
 from dbgpt.rag.retriever.rerank import Ranker
 from dbgpt.rag.retriever.rewrite import QueryRewrite
 from dbgpt.storage.vector_store.connector import VectorStoreConnector
 
 
-class EmbeddingRetrieverOperator(RetrieverOperator[Any, Any]):
+class EmbeddingRetrieverOperator(RetrieverOperator[Union[str, List[str]], List[Chunk]]):
     """The Embedding Retriever Operator."""
 
     def __init__(
@@ -32,7 +33,7 @@ class EmbeddingRetrieverOperator(RetrieverOperator[Any, Any]):
             rerank=rerank,
         )
 
-    def retrieve(self, query: Any) -> Any:
+    def retrieve(self, query: Union[str, List[str]]) -> List[Chunk]:
         """Retrieve the candidates."""
         if isinstance(query, str):
             return self._retriever.retrieve_with_scores(query, self._score_threshold)