Expose max_distance as an optional setting in multi vector queries

redisvl/query/aggregate.py

@@ -24,6 +24,7 @@ class Vector(BaseModel):
     field_name: str
     dtype: str = "float32"
     weight: float = 1.0
+    max_distance: float = 2.0
 
     @field_validator("dtype")
     @classmethod
@@ -36,6 +37,15 @@ def validate_dtype(cls, dtype: str) -> str:
             )
         return dtype
 
+    @field_validator("max_distance")
+    @classmethod
+    def validate_max_distance(cls, max_distance: float) -> float:
+        if not isinstance(max_distance, float) or isinstance(max_distance, int):
+            raise ValueError("max_distance must be a value between 0.0 and 2.0")
+        if max_distance < 0.0 or max_distance > 2.0:
+            raise ValueError("max_distance must be a value between 0.0 and 2.0")
+        return max_distance
+
     @model_validator(mode="after")
     def validate_vector(self) -> Self:
         """If the vector passed in is an array of float convert it to a byte string."""
@@ -361,14 +371,14 @@ def _build_query_string(self) -> str:
 
         # base KNN query
         range_queries = []
-        for i, (vector, field) in enumerate(
-            [(v.vector, v.field_name) for v in self._vectors]
+        for i, (vector, field, max_dist) in enumerate(
+            [(v.vector, v.field_name, v.max_distance) for v in self._vectors]
         ):
             range_queries.append(
-                f"@{field}:[VECTOR_RANGE 2.0 $vector_{i}]=>{{$YIELD_DISTANCE_AS: distance_{i}}}"
+                f"@{field}:[VECTOR_RANGE {max_dist} $vector_{i}]=>{{$YIELD_DISTANCE_AS: distance_{i}}}"
             )
 
-        range_query = " | ".join(range_queries)
+        range_query = " AND ".join(range_queries)
 
         filter_expression = self._filter_expression
         if isinstance(self._filter_expression, FilterExpression):

tests/integration/test_aggregation.py

@@ -675,6 +675,63 @@ def test_multivector_query_datatypes(index):
         )  # allow for small floating point error
 
 
+# paramatrized format is ((max_distance_1, max_distance_2), expected_num_results)
+@pytest.mark.parametrize(
+    "distances_and_results",
+    [
+        [(0.2, 0.2), 0],
+        [(0.9, 0.2), 0],
+        [(0.35, 0.5), 1],
+        [(0.2, 0.9), 2],
+        [(0.3, 1.0), 3],
+        [(1.3, 1.9), 6],
+    ],
+)
+def test_multivector_query_max_distances(index, distances_and_results):
+    skip_if_redis_version_below(index.client, "7.2.0")
+
+    vector_vals = [[0.1, 0.2, 0.5], [1.2, 0.3, -0.4, 0.7, 0.2]]
+    vector_fields = ["user_embedding", "image_embedding"]
+    distances, num_results = distances_and_results
+    return_fields = [
+        "distance_0",
+        "distance_1",
+        "score_0",
+        "score_1",
+        "user_embedding",
+        "image_embedding",
+    ]
+
+    vectors = []
+    for vector, field, distance in zip(vector_vals, vector_fields, distances):
+        vectors.append(Vector(vector=vector, field_name=field, max_distance=distance))
+
+    multi_query = MultiVectorQuery(
+        vectors=vectors,
+        return_fields=return_fields,
+        num_results=10,
+    )
+    results = index.query(multi_query)
+
+    # verify we get the right number of total results
+    assert len(results) == num_results
+
+    # verify we're filtering vectors based on max_distances
+    for i in range(len(results)):
+        assert float(results[i]["distance_0"]) <= distances[0]
+        assert float(results[i]["distance_1"]) <= distances[1]
+
+    # check we're indeed filtering on both distances and not just the lesser of the two
+    if results:
+        first_distances = [float(result["distance_0"]) for result in results]
+        second_distances = [float(result["distance_1"]) for result in results]
+
+        # this test only applies for our specific test case values
+        assert (max(first_distances) > distances[1]) or (
+            max(second_distances) > distances[0]
+        )
+
+
 def test_multivector_query_mixed_index(index):
     # test that we can do multi vector queries on indices with both a 'flat' and 'hnsw' index
     skip_if_redis_version_below(index.client, "7.2.0")

tests/integration/test_redis_cluster_support.py

@@ -89,6 +89,7 @@ def test_search_index_cluster_info(redis_cluster_url):
     finally:
         index.delete(drop=True)
 
+
 @pytest.mark.requires_cluster
 @pytest.mark.asyncio
 async def test_async_search_index_cluster_info(redis_cluster_url):
@@ -110,6 +111,7 @@ async def test_async_search_index_cluster_info(redis_cluster_url):
         await index.delete(drop=True)
         await client.aclose()
 
+
 @pytest.mark.requires_cluster
 @pytest.mark.asyncio
 async def test_async_search_index_client(redis_cluster_url):

tests/integration/test_search_index.py

@@ -304,6 +304,7 @@ def test_search_index_delete(index):
     assert not index.exists()
     assert index.name not in convert_bytes(index.client.execute_command("FT._LIST"))
 
+
 @pytest.mark.parametrize("num_docs", [0, 1, 5, 10, 2042])
 def test_search_index_clear(index, num_docs):
     index.create(overwrite=True, drop=True)

tests/unit/test_aggregation_types.py

@@ -315,6 +315,7 @@ def test_multi_vector_query():
     assert multivector_query._vectors[0].field_name == "field_1"
     assert multivector_query._vectors[0].weight == 1.0
     assert multivector_query._vectors[0].dtype == "float32"
+    assert multivector_query._vectors[0].max_distance == 2.0
     assert multivector_query._filter_expression == None
     assert multivector_query._num_results == 10
     assert multivector_query._loadfields == []
@@ -325,10 +326,21 @@ def test_multi_vector_query():
     vector_field_names = ["field_1", "field_2", "field_3", "field_4"]
     weights = [0.2, 0.5, 0.6, 0.1]
     dtypes = ["float32", "float32", "float32", "float32"]
+    distances = [2.0, 1.5, 0.4, 0.01]
 
     args = []
-    for vec, field, weight, dtype in zip(vectors, vector_field_names, weights, dtypes):
-        args.append(Vector(vector=vec, field_name=field, weight=weight, dtype=dtype))
+    for vec, field, weight, dtype, distance in zip(
+        vectors, vector_field_names, weights, dtypes, distances
+    ):
+        args.append(
+            Vector(
+                vector=vec,
+                field_name=field,
+                weight=weight,
+                dtype=dtype,
+                max_distance=distance,
+            )
+        )
 
     multivector_query = MultiVectorQuery(vectors=args)
 
@@ -358,16 +370,28 @@ def test_multi_vector_query_string():
     field_2 = "image embedding"
     weight_1 = 0.2
     weight_2 = 0.7
+    max_distance_1 = 0.7
+    max_distance_2 = 1.8
     multi_vector_query = MultiVectorQuery(
         vectors=[
-            Vector(vector=sample_vector_2, field_name=field_1, weight=weight_1),
-            Vector(vector=sample_vector_3, field_name=field_2, weight=weight_2),
+            Vector(
+                vector=sample_vector_2,
+                field_name=field_1,
+                weight=weight_1,
+                max_distance=max_distance_1,
+            ),
+            Vector(
+                vector=sample_vector_3,
+                field_name=field_2,
+                weight=weight_2,
+                max_distance=max_distance_2,
+            ),
         ]
     )
 
     assert (
         str(multi_vector_query)
-        == f"@{field_1}:[VECTOR_RANGE 2.0 $vector_0]=>{{$YIELD_DISTANCE_AS: distance_0}} | @{field_2}:[VECTOR_RANGE 2.0 $vector_1]=>{{$YIELD_DISTANCE_AS: distance_1}} SCORER TFIDF DIALECT 2 APPLY (2 - @distance_0)/2 AS score_0 APPLY (2 - @distance_1)/2 AS score_1 APPLY @score_0 * {weight_1} + @score_1 * {weight_2} AS combined_score SORTBY 2 @combined_score DESC MAX 10"
+        == f"@{field_1}:[VECTOR_RANGE {max_distance_1} $vector_0]=>{{$YIELD_DISTANCE_AS: distance_0}} AND @{field_2}:[VECTOR_RANGE {max_distance_2} $vector_1]=>{{$YIELD_DISTANCE_AS: distance_1}} SCORER TFIDF DIALECT 2 APPLY (2 - @distance_0)/2 AS score_0 APPLY (2 - @distance_1)/2 AS score_1 APPLY @score_0 * {weight_1} + @score_1 * {weight_2} AS combined_score SORTBY 2 @combined_score DESC MAX 10"
     )
 
 
@@ -411,6 +435,13 @@ def test_vector_object_validation():
         vec = Vector(vector=sample_vector, field_name="text embedding", dtype=dtype)
         assert isinstance(vec, Vector)
 
+    # max_distance is bounded to [0, 2.0]
+    for distance in [-0.1, 2.001, 35, -float("inf"), +float("inf")]:
+        with pytest.raises(ValueError):
+            vec = Vector(
+                vector=sample_vector, field_name="text embedding", max_distance=distance
+            )
+
 
 def test_vector_object_handles_byte_conversion():
     # test that passing an array of floats gets converted to bytes