Update AstraDBGraphVectorStore to match implementation of CassandraGraphVectorStore

libs/astradb/langchain_astradb/utils/astradb.py

@@ -380,18 +380,20 @@ def __init__(
                     service=collection_vector_service_options,
                     check_exists=False,
                 )
-            except DataAPIException:
+            except DataAPIException as data_api_exception:
                 # possibly the collection is preexisting and may have legacy,
                 # or custom, indexing settings: verify
                 collection_descriptors = list(self.database.list_collections())
-                if not self._validate_indexing_policy(
-                    collection_descriptors=collection_descriptors,
-                    collection_name=self.collection_name,
-                    requested_indexing_policy=requested_indexing_policy,
-                    default_indexing_policy=default_indexing_policy,
-                ):
-                    # other reasons for the exception
-                    raise
+                try:
+                    if not self._validate_indexing_policy(
+                        collection_descriptors=collection_descriptors,
+                        collection_name=self.collection_name,
+                        requested_indexing_policy=requested_indexing_policy,
+                        default_indexing_policy=default_indexing_policy,
+                    ):
+                        raise data_api_exception  # noqa: TRY201
+                except ValueError as validation_error:
+                    raise validation_error from data_api_exception
 
     async def _asetup_db(
         self,
@@ -420,20 +422,23 @@ async def _asetup_db(
                 service=collection_vector_service_options,
                 check_exists=False,
             )
-        except DataAPIException:
+        except DataAPIException as data_api_exception:
             # possibly the collection is preexisting and may have legacy,
             # or custom, indexing settings: verify
             collection_descriptors = [
                 coll_desc async for coll_desc in self.async_database.list_collections()
             ]
-            if not self._validate_indexing_policy(
-                collection_descriptors=collection_descriptors,
-                collection_name=self.collection_name,
-                requested_indexing_policy=requested_indexing_policy,
-                default_indexing_policy=default_indexing_policy,
-            ):
-                # other reasons for the exception
-                raise
+            try:
+                if not self._validate_indexing_policy(
+                    collection_descriptors=collection_descriptors,
+                    collection_name=self.collection_name,
+                    requested_indexing_policy=requested_indexing_policy,
+                    default_indexing_policy=default_indexing_policy,
+                ):
+                    # other reasons for the exception
+                    raise data_api_exception  # noqa: TRY201
+            except ValueError as validation_error:
+                raise validation_error from data_api_exception
 
     @staticmethod
     def _validate_indexing_policy(

libs/astradb/langchain_astradb/utils/mmr_traversal.py → libs/astradb/langchain_astradb/utils/mmr_helper.py

@@ -6,11 +6,9 @@
 from typing import TYPE_CHECKING, Iterable
 
 import numpy as np
-
-from langchain_astradb.utils.mmr import cosine_similarity
+from langchain_community.utils.math import cosine_similarity
 
 if TYPE_CHECKING:
-    from langchain_core.documents import Document
     from numpy.typing import NDArray
 
 
@@ -27,6 +25,7 @@ def _emb_to_ndarray(embedding: list[float]) -> NDArray[np.float32]:
 @dataclasses.dataclass
 class _Candidate:
     id: str
+    similarity: float
     weighted_similarity: float
     weighted_redundancy: float
     score: float = dataclasses.field(init=False)
@@ -72,6 +71,13 @@ class MmrHelper:
 
     selected_ids: list[str]
     """List of selected IDs (in selection order)."""
+
+    selected_mmr_scores: list[float]
+    """List of MMR score at the time each document is selected."""
+
+    selected_similarity_scores: list[float]
+    """List of similarity score for each selected document."""
+
     selected_embeddings: NDArray[np.float32]
     """(N, dim) ndarray with a row for each selected node."""
 
@@ -82,8 +88,6 @@ class MmrHelper:
 
     Same order as rows in `candidate_embeddings`.
     """
-    candidate_docs: dict[str, Document]
-    """Dict containing the documents associated with each candidate ID."""
     candidate_embeddings: NDArray[np.float32]
     """(N, dim) ndarray with a row for each candidate."""
 
@@ -106,12 +110,13 @@ def __init__(
         self.score_threshold = score_threshold
 
         self.selected_ids = []
+        self.selected_similarity_scores = []
+        self.selected_mmr_scores = []
 
         # List of selected embeddings (in selection order).
         self.selected_embeddings = np.ndarray((k, self.dimensions), dtype=np.float32)
 
         self.candidate_id_to_index = {}
-        self.candidate_docs = {}
 
         # List of the candidates.
         self.candidates = []
@@ -130,11 +135,11 @@ def _already_selected_embeddings(self) -> NDArray[np.float32]:
         selected = len(self.selected_ids)
         return np.vsplit(self.selected_embeddings, [selected])[0]
 
-    def _pop_candidate(self, candidate_id: str) -> NDArray[np.float32]:
+    def _pop_candidate(self, candidate_id: str) -> tuple[float, NDArray[np.float32]]:
         """Pop the candidate with the given ID.
 
         Returns:
-            The embedding of the candidate.
+            The similarity score and embedding of the candidate.
         """
         # Get the embedding for the id.
         index = self.candidate_id_to_index.pop(candidate_id)
@@ -150,12 +155,15 @@ def _pop_candidate(self, candidate_id: str) -> NDArray[np.float32]:
         # candidate_embeddings.
         last_index = self.candidate_embeddings.shape[0] - 1
 
+        similarity = 0.0
         if index == last_index:
             # Already the last item. We don't need to swap.
-            self.candidates.pop()
+            similarity = self.candidates.pop().similarity
         else:
             self.candidate_embeddings[index] = self.candidate_embeddings[last_index]
 
+            similarity = self.candidates[index].similarity
+
             old_last = self.candidates.pop()
             self.candidates[index] = old_last
             self.candidate_id_to_index[old_last.id] = index
@@ -164,7 +172,7 @@ def _pop_candidate(self, candidate_id: str) -> NDArray[np.float32]:
             0
         ]
 
-        return embedding
+        return similarity, embedding
 
     def pop_best(self) -> str | None:
         """Select and pop the best item being considered.
@@ -179,11 +187,13 @@ def pop_best(self) -> str | None:
 
         # Get the selection and remove from candidates.
         selected_id = self.best_id
-        selected_embedding = self._pop_candidate(selected_id)
+        selected_similarity, selected_embedding = self._pop_candidate(selected_id)
 
         # Add the ID and embedding to the selected information.
         selection_index = len(self.selected_ids)
         self.selected_ids.append(selected_id)
+        self.selected_mmr_scores.append(self.best_score)
+        self.selected_similarity_scores.append(selected_similarity)
         self.selected_embeddings[selection_index] = selected_embedding
 
         # Reset the best score / best ID.
@@ -203,9 +213,7 @@ def pop_best(self) -> str | None:
 
         return selected_id
 
-    def add_candidates(
-        self, candidates: dict[str, tuple[Document, list[float]]]
-    ) -> None:
+    def add_candidates(self, candidates: dict[str, list[float]]) -> None:
         """Add candidates to the consideration set."""
         # Determine the keys to actually include.
         # These are the candidates that aren't already selected
@@ -227,9 +235,8 @@ def add_candidates(
         for index, candidate_id in enumerate(include_ids):
             if candidate_id in include_ids:
                 self.candidate_id_to_index[candidate_id] = offset + index
-                doc, embedding = candidates[candidate_id]
+                embedding = candidates[candidate_id]
                 new_embeddings[index] = embedding
-                self.candidate_docs[candidate_id] = doc
 
         # Compute the similarity to the query.
         similarity = cosine_similarity(new_embeddings, self.query_embedding)
@@ -245,6 +252,7 @@ def add_candidates(
                 max_redundancy = redundancy[index].max()
             candidate = _Candidate(
                 id=candidate_id,
+                similarity=similarity[index][0],
                 weighted_similarity=self.lambda_mult * similarity[index][0],
                 weighted_redundancy=self.lambda_mult_complement * max_redundancy,
             )