fix: do not accept empty vectors and multivectors in local mode (#1405)

* fix: do not accept empty vectors and multivectors in local mode

* fix: do not modify points if vector does not pass validation

qdrant_client/local/local_collection.py

@@ -100,6 +100,25 @@ def to_jsonable_python(x: Any) -> Any:
         return json.loads(json.dumps(x, allow_nan=True, default=_to_jsonable_python))
 
 
+def validate_dense_vector(vector: Any, vector_name: str) -> None:
+    """Reject empty dense vectors, as the server does at write time."""
+    if len(vector) == 0:
+        raise ValueError(f"Wrong input: Dense vector must not be empty for vector '{vector_name}'")
+
+
+def validate_multivector(vector: Any, vector_name: str) -> None:
+    """Reject empty multivectors and multivectors holding empty vectors, as the server does."""
+    if len(vector) == 0:
+        raise ValueError(f"Wrong input: Multivector must not be empty for vector '{vector_name}'")
+
+    for sub_vector in vector:
+        if hasattr(sub_vector, "__len__") and len(sub_vector) == 0:
+            raise ValueError(
+                "Wrong input: All vectors of a multivector must be non-empty "
+                f"for vector '{vector_name}'"
+            )
+
+
 class LocalCollection:
     """
     LocalCollection is a class that represents a collection of vectors in the local storage.
@@ -393,6 +412,20 @@ class LocalCollection:
 
         raise ValueError(f"Malformed config.vectors: {self.config.vectors}")
 
+    def _validate_dense_or_multivector(self, vector: Any, vector_name: str) -> None:
+        """Reject empty vectors on the write path, the way the server does.
+
+        Sparse vectors are validated by `validate_sparse_vector`; an empty sparse vector is
+        legitimate, so it is not routed here.
+        """
+        if vector is None:
+            return
+
+        if vector_name in self.multivectors:
+            validate_multivector(vector, vector_name)
+        elif vector_name in self.vectors:
+            validate_dense_vector(vector, vector_name)
+
     @classmethod
     def _check_include_pattern(cls, pattern: str, key: str) -> bool:
         """
@@ -2613,6 +2646,8 @@ class LocalCollection:
                     validate_sparse_vector(vector)
                     # sort sparse vector by indices before persistence
                     updated_sparse_vectors[vector_name] = sort_sparse_vector(vector)
+                else:
+                    self._validate_dense_or_multivector(vector, vector_name)
             # update point.vector with the modified values after iteration
             point.vector.update(updated_sparse_vectors)
         else:
@@ -2627,6 +2662,7 @@ class LocalCollection:
                 )
             if not self.vectors and not self.multivectors:
                 raise ValueError("Wrong input: Not existing vector name error")
+            self._validate_dense_or_multivector(point.vector, DEFAULT_VECTOR_NAME)
 
         if isinstance(point.id, uuid.UUID):
             point.id = str(point.id)
@@ -2703,23 +2739,31 @@ class LocalCollection:
     def _update_named_vectors(
         self, idx: int, vectors: dict[str, list[float] | SparseVector | list[list[float]]]
     ) -> None:
+        validated: list[tuple[str, Any]] = []
         for vector_name, vector in vectors.items():
             if vector_name not in self._all_vectors_keys:
                 raise ValueError(f"Wrong input: Not existing vector name error: {vector_name}")
 
-            self.deleted_per_vector[vector_name][idx] = 0
-
             if isinstance(vector, SparseVector):
                 validate_sparse_vector(vector)
-                old_vector = self.sparse_vectors[vector_name][idx]
-                self._update_idf_remove(old_vector, vector_name)
-                new_vector = sort_sparse_vector(vector)
-                self.sparse_vectors[vector_name][idx] = new_vector
-                self._update_idf_append(new_vector, vector_name)
+                validated.append((vector_name, sort_sparse_vector(vector)))
                 continue
 
+            self._validate_dense_or_multivector(vector, vector_name)
             vector_np = np.array(vector, dtype=np.float32)
             assert not np.isnan(vector_np).any(), "Vector contains NaN values"
+            validated.append((vector_name, vector_np))
+
+        for vector_name, vector_np in validated:
+            self.deleted_per_vector[vector_name][idx] = 0
+
+            if isinstance(vector_np, SparseVector):
+                old_vector = self.sparse_vectors[vector_name][idx]
+                self._update_idf_remove(old_vector, vector_name)
+                self.sparse_vectors[vector_name][idx] = vector_np
+                self._update_idf_append(vector_np, vector_name)
+                continue
+
             params = self.get_vector_params(vector_name)
             if vector_name in self.vectors:
                 if params.distance == models.Distance.COSINE:

tests/congruence_tests/test_multivector_updates.py

@@ -5,6 +5,7 @@ from collections import defaultdict
 import pytest
 
 from qdrant_client.http import models
+from qdrant_client.http.exceptions import UnexpectedResponse
 from tests.congruence_tests.test_common import (
     COLLECTION_NAME,
     compare_collections,
@@ -57,9 +58,7 @@ def test_upsert():
         COLLECTION_NAME,
         scroll_filter=id_filter,
         limit=1,
-    )[
-        0
-    ][0]
+    )[0][0]
     remote_old_point = remote_client.scroll(COLLECTION_NAME, scroll_filter=id_filter, limit=1)[0][
         0
     ]
@@ -203,3 +202,96 @@ def test_upload_uuid_in_batches():
         UPLOAD_NUM_VECTORS,
         attrs=("points_count",),
     )
+
+
+def test_upsert_empty_multivector():
+    """Both clients must reject an empty multivector on every write path."""
+    points = generate_multivector_fixtures(UPLOAD_NUM_VECTORS)
+
+    local_client = init_local()
+    init_client(local_client, points, vectors_config=multi_vector_config)
+
+    remote_client = init_remote()
+    init_client(remote_client, points, vectors_config=multi_vector_config)
+
+    existing_id = points[0].id
+    new_point_id = UPLOAD_NUM_VECTORS + 1
+
+    # a multivector with no vectors at all, and one holding an empty vector
+    cases = (
+        ([], "Multivector must not be empty"),
+        ([[]], "vectors of a multivector must be non-empty"),
+    )
+    for empty_multivector, local_error in cases:
+        upsert_structs = (
+            [models.PointStruct(id=new_point_id, vector={"multi-text": empty_multivector})],
+            [models.PointStruct(id=existing_id, vector={"multi-text": empty_multivector})],
+            models.Batch(ids=[new_point_id], vectors={"multi-text": [empty_multivector]}),
+        )
+        for upsert_struct in upsert_structs:
+            with pytest.raises(ValueError, match=local_error):
+                local_client.upsert(COLLECTION_NAME, upsert_struct)
+
+            with pytest.raises(UnexpectedResponse):
+                remote_client.upsert(COLLECTION_NAME, upsert_struct)
+
+        point_vectors = [
+            models.PointVectors(id=existing_id, vector={"multi-text": empty_multivector})
+        ]
+        with pytest.raises(ValueError, match=local_error):
+            local_client.update_vectors(COLLECTION_NAME, points=point_vectors)
+
+        with pytest.raises(UnexpectedResponse):
+            remote_client.update_vectors(COLLECTION_NAME, points=point_vectors)
+
+    compare_collections(
+        local_client,
+        remote_client,
+        UPLOAD_NUM_VECTORS,
+        attrs=("points_count",),
+    )
+
+
+def test_rejected_empty_multivector_update_leaves_point_untouched():
+    """A rejected update_vectors request must not make an absent multivector visible.
+
+    Regression: validation used to run after `deleted_per_vector` was cleared, so rejecting
+    an empty multivector still exposed the placeholder to retrieval and search.
+    """
+    local_client = init_local()
+    remote_client = init_remote()
+
+    mvc = models.MultiVectorConfig(comparator=models.MultiVectorComparator.MAX_SIM)
+    vectors_config = {
+        "a": models.VectorParams(size=4, distance=models.Distance.COSINE, multivector_config=mvc),
+        "b": models.VectorParams(size=4, distance=models.Distance.COSINE, multivector_config=mvc),
+    }
+    local_client.create_collection(COLLECTION_NAME, vectors_config=vectors_config)
+    if remote_client.collection_exists(collection_name=COLLECTION_NAME):
+        remote_client.delete_collection(collection_name=COLLECTION_NAME)
+    remote_client.create_collection(COLLECTION_NAME, vectors_config=vectors_config)
+
+    query = [[1.0, 0.0, 0.0, 0.0]]
+
+    # point 1 has no "a" at all, so "a" is backed by a placeholder marked deleted
+    absent_a = [models.PointStruct(id=1, vector={"b": query})]
+    local_client.upsert(COLLECTION_NAME, absent_a)
+    remote_client.upsert(COLLECTION_NAME, absent_a, wait=True)
+
+    for empty_multivector, local_error in (
+        ([], "Multivector must not be empty"),
+        ([[]], "vectors of a multivector must be non-empty"),
+    ):
+        point_vectors = [models.PointVectors(id=1, vector={"a": empty_multivector})]
+        with pytest.raises(ValueError, match=local_error):
+            local_client.update_vectors(COLLECTION_NAME, points=point_vectors)
+        with pytest.raises(UnexpectedResponse):
+            remote_client.update_vectors(COLLECTION_NAME, points=point_vectors, wait=True)
+
+        for client in (local_client, remote_client):
+            record = client.retrieve(COLLECTION_NAME, ids=[1], with_vectors=True)[0]
+            assert "a" not in record.vector
+            hits = client.query_points(COLLECTION_NAME, query=query, using="a", limit=5).points
+            assert hits == []
+
+    compare_collections(local_client, remote_client, 1, attrs=("points_count",))

tests/congruence_tests/test_updates.py

@@ -343,6 +343,116 @@ def test_upload_wrong_vectors():
         )
 
 
+def test_upsert_empty_dense_vector():
+    """Both clients must reject an empty dense vector on every write path.
+
+    An empty *sparse* vector, on the other hand, is legitimate and must stay accepted.
+    """
+    local_client = init_local()
+    remote_client = init_remote()
+
+    vectors_config = {"text": models.VectorParams(size=2, distance=models.Distance.COSINE)}
+    sparse_vectors_config = {"text-sparse": models.SparseVectorParams()}
+
+    local_client.create_collection(
+        collection_name=COLLECTION_NAME,
+        vectors_config=vectors_config,
+        sparse_vectors_config=sparse_vectors_config,
+    )
+    if remote_client.collection_exists(collection_name=COLLECTION_NAME):
+        remote_client.delete_collection(collection_name=COLLECTION_NAME)
+    remote_client.create_collection(
+        collection_name=COLLECTION_NAME,
+        vectors_config=vectors_config,
+        sparse_vectors_config=sparse_vectors_config,
+    )
+
+    # a valid point to overwrite later
+    valid_points = [models.PointStruct(id=1, vector={"text": [0.1, 0.3]})]
+    local_client.upsert(COLLECTION_NAME, valid_points)
+    remote_client.upsert(COLLECTION_NAME, valid_points)
+
+    empty_points = [models.PointStruct(id=2, vector={"text": []})]
+    overwrite_points = [models.PointStruct(id=1, vector={"text": []})]
+    empty_batch = models.Batch(ids=[3], vectors={"text": [[]]})
+
+    for points in (empty_points, overwrite_points, empty_batch):
+        with pytest.raises(ValueError, match="Dense vector must not be empty"):
+            local_client.upsert(COLLECTION_NAME, points)
+
+        with pytest.raises(qdrant_client.http.exceptions.UnexpectedResponse):
+            remote_client.upsert(COLLECTION_NAME, points)
+
+    empty_point_vectors = [models.PointVectors(id=1, vector={"text": []})]
+    with pytest.raises(ValueError, match="Dense vector must not be empty"):
+        local_client.update_vectors(COLLECTION_NAME, points=empty_point_vectors)
+
+    with pytest.raises(qdrant_client.http.exceptions.UnexpectedResponse):
+        remote_client.update_vectors(COLLECTION_NAME, points=empty_point_vectors)
+
+    # an empty sparse vector is valid input for both clients
+    empty_sparse_points = [
+        models.PointStruct(
+            id=4, vector={"text-sparse": models.SparseVector(indices=[], values=[])}
+        )
+    ]
+    local_client.upsert(COLLECTION_NAME, empty_sparse_points)
+    remote_client.upsert(COLLECTION_NAME, empty_sparse_points, wait=True)
+
+    compare_collections(local_client, remote_client, UPLOAD_NUM_VECTORS)
+
+
+def test_rejected_empty_vector_update_leaves_point_untouched():
+    """A rejected update_vectors request must not change the point in any way.
+
+    Regression: validation used to run after `deleted_per_vector` was cleared, so rejecting
+    an empty vector still made an absent vector's placeholder visible to search, and a valid
+    vector supplied alongside the rejected one was written anyway.
+    """
+    local_client = init_local()
+    remote_client = init_remote()
+
+    vectors_config = {
+        "a": models.VectorParams(size=4, distance=models.Distance.COSINE),
+        "b": models.VectorParams(size=4, distance=models.Distance.COSINE),
+    }
+    local_client.create_collection(COLLECTION_NAME, vectors_config=vectors_config)
+    if remote_client.collection_exists(collection_name=COLLECTION_NAME):
+        remote_client.delete_collection(collection_name=COLLECTION_NAME)
+    remote_client.create_collection(COLLECTION_NAME, vectors_config=vectors_config)
+
+    orig = [1.0, 0.0, 0.0, 0.0]
+    other = [0.0, 1.0, 0.0, 0.0]
+
+    # point 1 has no "a" at all, so "a" is backed by a placeholder marked deleted
+    absent_a = [models.PointStruct(id=1, vector={"b": orig})]
+    local_client.upsert(COLLECTION_NAME, absent_a)
+    remote_client.upsert(COLLECTION_NAME, absent_a, wait=True)
+
+    empty_a = [models.PointVectors(id=1, vector={"a": []})]
+    with pytest.raises(ValueError, match="Dense vector must not be empty"):
+        local_client.update_vectors(COLLECTION_NAME, points=empty_a)
+    with pytest.raises(qdrant_client.http.exceptions.UnexpectedResponse):
+        remote_client.update_vectors(COLLECTION_NAME, points=empty_a, wait=True)
+
+    # "a" must still be absent for both clients, and must not be searchable
+    for client in (local_client, remote_client):
+        assert "a" not in client.retrieve(COLLECTION_NAME, ids=[1], with_vectors=True)[0].vector
+        assert client.query_points(COLLECTION_NAME, query=orig, using="a", limit=5).points == []
+
+    # a valid vector supplied next to the rejected one must not be written either
+    mixed = [models.PointVectors(id=1, vector={"b": other, "a": []})]
+    with pytest.raises(ValueError, match="Dense vector must not be empty"):
+        local_client.update_vectors(COLLECTION_NAME, points=mixed)
+    with pytest.raises(qdrant_client.http.exceptions.UnexpectedResponse):
+        remote_client.update_vectors(COLLECTION_NAME, points=mixed, wait=True)
+
+    for client in (local_client, remote_client):
+        assert client.retrieve(COLLECTION_NAME, ids=[1], with_vectors=True)[0].vector["b"] == orig
+
+    compare_collections(local_client, remote_client, UPLOAD_NUM_VECTORS)
+
+
 def test_upsert_without_vector_name():
     local_client = init_local()
     remote_client = init_remote()