Merge pull request #1077 from mdelapenya/weaviate-return-no-errors

fix(vectorstores:weaviate|pinecone): do not return error when zero documents are retrieved

vectorstores/pinecone/pinecone.go

@@ -22,6 +22,7 @@ var (
 	ErrEmbedderWrongNumberVectors = errors.New(
 		"number of vectors from embedder does not match number of documents",
 	)
+	// Deprecated: ErrEmptyResponse is not used anymore and will be removed in the future.
 	// ErrEmptyResponse is returned if the API gives an empty response.
 	ErrEmptyResponse         = errors.New("empty response")
 	ErrInvalidScoreThreshold = errors.New(
@@ -170,7 +171,7 @@ func (s Store) SimilaritySearch(ctx context.Context, query string, numDocuments
 	}
 
 	if len(queryResult.Matches) == 0 {
-		return nil, ErrEmptyResponse
+		return []schema.Document{}, nil
 	}
 
 	return s.getDocumentsFromMatches(queryResult, scoreThreshold)

vectorstores/weaviate/weaviate.go

@@ -232,10 +232,11 @@ func (s Store) parseDocumentsByGraphQLResponse(res *models.GraphQLResponse) ([]s
 		return nil, ErrEmptyResponse
 	}
 	items, ok := data.([]any)
+
+	docs := make([]schema.Document, 0, len(items))
 	if !ok || len(items) == 0 {
-		return nil, ErrEmptyResponse
+		return docs, nil
 	}
-	docs := make([]schema.Document, 0, len(items))
 	for _, item := range items {
 		itemMap, ok := item.(map[string]any)
 		if !ok {