fix: fix validation error when passing "*" to $maxHops

Author: matmoncon

pyneo4j_ogm/queries/validators.py

@@ -8,7 +8,6 @@
 from typing import Any, Dict, List, Literal, Optional, Type, Union
 
 from pydantic import BaseModel, Field, ValidationError
-from pydantic.class_validators import root_validator, validator
 
 from pyneo4j_ogm.logger import logger
 from pyneo4j_ogm.pydantic_utils import (
@@ -25,6 +24,8 @@
 
 if IS_PYDANTIC_V2:
     from pydantic import field_validator, model_validator
+else:
+    from pydantic.class_validators import root_validator, validator
 
 
 def _normalize_fields(cls: Type[BaseModel], values: Any) -> Any:
@@ -394,7 +395,7 @@ class MultiHopFiltersModel(BaseModel):
     """
 
     min_hops_: Optional[int] = Field(alias="$minHops", ge=0, default=None)
-    max_hops_: Optional[Union[int, Literal["*"]]] = Field(alias="$maxHops", ge=1, default="*")
+    max_hops_: Optional[Union[int, Literal["*"]]] = Field(alias="$maxHops", default="*")
     node_: MultiHopNodeModel = Field(alias="$node")
     relationships_: Optional[List[MultiHopRelationshipOperatorsModel]] = Field(alias="$relationships", default=None)
     direction_: Optional[RelationshipMatchDirection] = Field(
@@ -404,13 +405,25 @@ class MultiHopFiltersModel(BaseModel):
     if IS_PYDANTIC_V2:
         normalize_and_validate_fields = model_validator(mode="after")(_normalize_fields)
 
+        @field_validator("max_hops_")
+        def validate_max_hops_v2(cls, v: Any) -> Any:
+            if isinstance(v, int) and v <= 0:
+                raise ValueError("$maxHops must be greater than 0")
+            return v
+
         model_config = {
             "extra": "allow",
             "use_enum_values": True,
         }
     else:
         normalize_and_validate_fields = root_validator(allow_reuse=True)(_normalize_fields)
 
+        @validator("max_hops_")
+        def validate_max_hops_v1(cls, v: Any) -> Any:
+            if isinstance(v, int) and v <= 0:
+                raise ValueError("$maxHops must be greater than 0")
+            return v
+
         class Config:
             """
             Pydantic configuration

tests/test_query_builder_filters.py

@@ -111,6 +111,38 @@ def test_valid_multi_hop_filters(query_builder: QueryBuilder):
     assert query_builder.parameters == {"_n_0": ["Node"], "_n_1": "Jenny"}
 
 
+def test_valid_multi_hop_filters_with_min_hops(query_builder: QueryBuilder):
+    query_builder.multi_hop_filters({"$node": {"$labels": "Node", "name": "Jenny"}, "$minHops": 3})
+
+    assert query_builder.query["match"] == ", path = (n)-[r*3..]->(m)"
+    assert query_builder.query["where"] == "ALL(i IN labels(m) WHERE i IN $_n_0) AND m.name = $_n_1"
+    assert query_builder.parameters == {"_n_0": ["Node"], "_n_1": "Jenny"}
+
+
+def test_valid_multi_hop_filters_with_max_hops(query_builder: QueryBuilder):
+    query_builder.multi_hop_filters({"$node": {"$labels": "Node", "name": "Jenny"}, "$maxHops": 3})
+
+    assert query_builder.query["match"] == ", path = (n)-[r*..3]->(m)"
+    assert query_builder.query["where"] == "ALL(i IN labels(m) WHERE i IN $_n_0) AND m.name = $_n_1"
+    assert query_builder.parameters == {"_n_0": ["Node"], "_n_1": "Jenny"}
+
+
+def test_valid_multi_hop_filters_with_max_hops_special_char(query_builder: QueryBuilder):
+    query_builder.multi_hop_filters({"$node": {"$labels": "Node", "name": "Jenny"}, "$maxHops": "*"})
+
+    assert query_builder.query["match"] == ", path = (n)-[r*]->(m)"
+    assert query_builder.query["where"] == "ALL(i IN labels(m) WHERE i IN $_n_0) AND m.name = $_n_1"
+    assert query_builder.parameters == {"_n_0": ["Node"], "_n_1": "Jenny"}
+
+
+def test_valid_multi_hop_filters_with_min_and_max_hops(query_builder: QueryBuilder):
+    query_builder.multi_hop_filters({"$node": {"$labels": "Node", "name": "Jenny"}, "$minHops": 3, "$maxHops": 5})
+
+    assert query_builder.query["match"] == ", path = (n)-[r*3..5]->(m)"
+    assert query_builder.query["where"] == "ALL(i IN labels(m) WHERE i IN $_n_0) AND m.name = $_n_1"
+    assert query_builder.parameters == {"_n_0": ["Node"], "_n_1": "Jenny"}
+
+
 def test_valid_multi_hop_filters_with_ref(query_builder: QueryBuilder):
     query_builder.multi_hop_filters({"$node": {"$labels": "Node", "name": "Jenny"}}, start_ref="start", end_ref="end")