from enum import Enum
from functools import wraps
from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Union
from redisvl.utils.token_escaper import TokenEscaper
# disable mypy error for dunder method overrides
# mypy: disable-error-code="override"
class FilterOperator(Enum):
EQ = 1
NE = 2
LT = 3
GT = 4
LE = 5
GE = 6
OR = 7
AND = 8
LIKE = 9
IN = 10
class FilterField:
escaper: TokenEscaper = TokenEscaper()
OPERATORS: Dict[FilterOperator, str] = {}
def __init__(self, field: str):
self._field = field
self._value: Any = None
self._operator: FilterOperator = FilterOperator.EQ
def equals(self, other: "FilterField") -> bool:
if not isinstance(other, type(self)):
return False
return (self._field == other._field) and (self._value == other._value)
def _set_value(
self,
val: Any,
val_type: Union[type, Tuple[type, ...]],
operator: FilterOperator,
):
# check that the operator is supported by this class
if operator not in self.OPERATORS:
raise ValueError(
f"Operator {operator} not supported by {self.__class__.__name__}. "
+ f"Supported operators are {self.OPERATORS.values()}"
)
# check that the value is of the proper type
if not isinstance(val, val_type):
raise TypeError(
f"Right side argument passed to operator {self.OPERATORS[operator]} "
f"with left side "
f"argument {self.__class__.__name__} must be of type {val_type}"
)
self._value = val
self._operator = operator
def check_operator_misuse(func: Callable) -> Callable:
@wraps(func)
def wrapper(instance: Any, *args: List[Any], **kwargs: Dict[str, Any]) -> Any:
# Extracting 'other' from positional arguments or keyword arguments
other = kwargs.get("other") if "other" in kwargs else None
if not other:
for arg in args:
if isinstance(arg, type(instance)):
other = arg
break
if isinstance(other, type(instance)):
raise ValueError(
"Equality operators are overridden for FilterExpression creation. Use "
".equals() for equality checks"
)
return func(instance, *args, **kwargs)
return wrapper
[docs]
class Tag(FilterField):
"""A Tag filter can be applied to Tag fields"""
OPERATORS: Dict[FilterOperator, str] = {
FilterOperator.EQ: "==",
FilterOperator.NE: "!=",
FilterOperator.IN: "==",
}
OPERATOR_MAP: Dict[FilterOperator, str] = {
FilterOperator.EQ: "@%s:{%s}",
FilterOperator.NE: "(-@%s:{%s})",
FilterOperator.IN: "@%s:{%s}",
}
SUPPORTED_VAL_TYPES = (list, set, tuple, str, type(None))
def _set_tag_value(
self, other: Union[List[str], Set[str], str], operator: FilterOperator
):
if isinstance(other, (list, set, tuple)):
try:
# "if val" clause removes non-truthy values from list
other = [str(val) for val in other if val]
except ValueError:
raise ValueError("All tags within collection must be strings")
# above to catch the "" case
elif not other:
other = []
elif isinstance(other, str):
other = [other]
self._set_value(other, self.SUPPORTED_VAL_TYPES, operator)
[docs]
@check_operator_misuse
def __eq__(self, other: Union[List[str], str]) -> "FilterExpression":
"""Create a Tag equality filter expression.
Args:
other (Union[List[str], str]): The tag(s) to filter on.
.. code-block:: python
from redisvl.query.filter import Tag
f = Tag("brand") == "nike"
"""
self._set_tag_value(other, FilterOperator.EQ)
return FilterExpression(str(self))
[docs]
@check_operator_misuse
def __ne__(self, other) -> "FilterExpression":
"""Create a Tag inequality filter expression.
Args:
other (Union[List[str], str]): The tag(s) to filter on.
.. code-block:: python
from redisvl.query.filter import Tag
f = Tag("brand") != "nike"
"""
self._set_tag_value(other, FilterOperator.NE)
return FilterExpression(str(self))
@property
def _formatted_tag_value(self) -> str:
return "|".join([self.escaper.escape(tag) for tag in self._value])
[docs]
def __str__(self) -> str:
"""Return the Redis Query string for the Tag filter"""
if not self._value:
return "*"
return self.OPERATOR_MAP[self._operator] % (
self._field,
self._formatted_tag_value,
)
class GeoSpec:
GEO_UNITS = ["m", "km", "mi", "ft"]
# class for the operand for FilterExpressions with Geo
def __init__(self, longitude: float, latitude: float, unit: str = "km"):
if unit.lower() not in self.GEO_UNITS:
raise ValueError(f"Unit must be one of {self.GEO_UNITS}")
self._longitude = longitude
self._latitude = latitude
self._unit = unit.lower()
[docs]
class GeoRadius(GeoSpec):
"""A GeoRadius is a GeoSpec representing a geographic radius."""
[docs]
def __init__(
self,
longitude: float,
latitude: float,
radius: int = 1,
unit: str = "km",
):
"""Create a GeoRadius specification (GeoSpec)
Args:
longitude (float): The longitude of the center of the radius.
latitude (float): The latitude of the center of the radius.
radius (int, optional): The radius of the circle. Defaults to 1.
unit (str, optional): The unit of the radius. Defaults to "km".
Raises:
ValueError: If the unit is not one of "m", "km", "mi", or "ft".
"""
super().__init__(longitude, latitude, unit)
self._radius = radius
def get_args(self) -> List[Union[float, int, str]]:
return [self._longitude, self._latitude, self._radius, self._unit]
[docs]
class Geo(FilterField):
"""A Geo is a FilterField representing a geographic (lat/lon) field in a
Redis index."""
OPERATORS: Dict[FilterOperator, str] = {
FilterOperator.EQ: "==",
FilterOperator.NE: "!=",
}
OPERATOR_MAP: Dict[FilterOperator, str] = {
FilterOperator.EQ: "@%s:[%s %s %i %s]",
FilterOperator.NE: "(-@%s:[%s %s %i %s])",
}
SUPPORTED_VAL_TYPES = (GeoSpec, type(None))
[docs]
@check_operator_misuse
def __eq__(self, other) -> "FilterExpression":
"""Create a geographic filter within a specified GeoRadius.
Args:
other (GeoRadius): The geographic spec to filter on.
.. code-block:: python
from redisvl.query.filter import Geo, GeoRadius
f = Geo("location") == GeoRadius(-122.4194, 37.7749, 1, unit="m")
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.EQ) # type: ignore
return FilterExpression(str(self))
[docs]
@check_operator_misuse
def __ne__(self, other) -> "FilterExpression":
"""Create a geographic filter outside of a specified GeoRadius.
Args:
other (GeoRadius): The geographic spec to filter on.
.. code-block:: python
from redisvl.query.filter import Geo, GeoRadius
f = Geo("location") != GeoRadius(-122.4194, 37.7749, 1, unit="m")
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.NE) # type: ignore
return FilterExpression(str(self))
[docs]
def __str__(self) -> str:
"""Return the Redis Query string for the Geo filter"""
if not self._value:
return "*"
return self.OPERATOR_MAP[self._operator] % (
self._field,
*self._value.get_args(),
)
[docs]
class Num(FilterField):
"""A Num is a FilterField representing a numeric field in a Redis index."""
OPERATORS: Dict[FilterOperator, str] = {
FilterOperator.EQ: "==",
FilterOperator.NE: "!=",
FilterOperator.LT: "<",
FilterOperator.GT: ">",
FilterOperator.LE: "<=",
FilterOperator.GE: ">=",
}
OPERATOR_MAP: Dict[FilterOperator, str] = {
FilterOperator.EQ: "@%s:[%s %s]",
FilterOperator.NE: "(-@%s:[%s %s])",
FilterOperator.GT: "@%s:[(%s +inf]",
FilterOperator.LT: "@%s:[-inf (%s]",
FilterOperator.GE: "@%s:[%s +inf]",
FilterOperator.LE: "@%s:[-inf %s]",
}
SUPPORTED_VAL_TYPES = (int, float, type(None))
[docs]
def __eq__(self, other: int) -> "FilterExpression":
"""Create a Numeric equality filter expression.
Args:
other (int): The value to filter on.
.. code-block:: python
from redisvl.query.filter import Num
f = Num("zipcode") == 90210
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.EQ)
return FilterExpression(str(self))
[docs]
def __ne__(self, other: int) -> "FilterExpression":
"""Create a Numeric inequality filter expression.
Args:
other (int): The value to filter on.
.. code-block:: python
from redisvl.query.filter import Num
f = Num("zipcode") != 90210
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.NE)
return FilterExpression(str(self))
[docs]
def __gt__(self, other: int) -> "FilterExpression":
"""Create a Numeric greater than filter expression.
Args:
other (int): The value to filter on.
.. code-block:: python
from redisvl.query.filter import Num
f = Num("age") > 18
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.GT)
return FilterExpression(str(self))
[docs]
def __lt__(self, other: int) -> "FilterExpression":
"""Create a Numeric less than filter expression.
Args:
other (int): The value to filter on.
.. code-block:: python
from redisvl.query.filter import Num
f = Num("age") < 18
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.LT)
return FilterExpression(str(self))
[docs]
def __ge__(self, other: int) -> "FilterExpression":
"""Create a Numeric greater than or equal to filter expression.
Args:
other (int): The value to filter on.
.. code-block:: python
from redisvl.query.filter import Num
f = Num("age") >= 18
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.GE)
return FilterExpression(str(self))
[docs]
def __le__(self, other: int) -> "FilterExpression":
"""Create a Numeric less than or equal to filter expression.
Args:
other (int): The value to filter on.
.. code-block:: python
from redisvl.query.filter import Num
f = Num("age") <= 18
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.LE)
return FilterExpression(str(self))
[docs]
def __str__(self) -> str:
"""Return the Redis Query string for the Numeric filter"""
if self._value is None:
return "*"
if self._operator == FilterOperator.EQ or self._operator == FilterOperator.NE:
return self.OPERATOR_MAP[self._operator] % (
self._field,
self._value,
self._value,
)
else:
return self.OPERATOR_MAP[self._operator] % (self._field, self._value)
[docs]
class Text(FilterField):
"""A Text is a FilterField representing a text field in a Redis index."""
OPERATORS: Dict[FilterOperator, str] = {
FilterOperator.EQ: "==",
FilterOperator.NE: "!=",
FilterOperator.LIKE: "%",
}
OPERATOR_MAP: Dict[FilterOperator, str] = {
FilterOperator.EQ: '@%s:("%s")',
FilterOperator.NE: '(-@%s:"%s")',
FilterOperator.LIKE: "@%s:(%s)",
}
SUPPORTED_VAL_TYPES = (str, type(None))
[docs]
@check_operator_misuse
def __eq__(self, other: str) -> "FilterExpression":
"""Create a Text equality filter expression. These expressions yield
filters that enforce an exact match on the supplied term(s).
Args:
other (str): The text value to filter on.
.. code-block:: python
from redisvl.query.filter import Text
f = Text("job") == "engineer"
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.EQ)
return FilterExpression(str(self))
[docs]
@check_operator_misuse
def __ne__(self, other: str) -> "FilterExpression":
"""Create a Text inequality filter expression. These expressions yield
negated filters on exact matches on the supplied term(s). Opposite of an
equality filter expression.
Args:
other (str): The text value to filter on.
.. code-block:: python
from redisvl.query.filter import Text
f = Text("job") != "engineer"
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.NE)
return FilterExpression(str(self))
[docs]
def __mod__(self, other: str) -> "FilterExpression":
"""Create a Text "LIKE" filter expression. A flexible expression that
yields filters that can use a variety of additional operators like
wildcards (*), fuzzy matches (%%), or combinatorics (|) of the supplied
term(s).
Args:
other (str): The text value to filter on.
.. code-block:: python
from redisvl.query.filter import Text
f = Text("job") % "engine*" # suffix wild card match
f = Text("job") % "%%engine%%" # fuzzy match w/ Levenshtein Distance
f = Text("job") % "engineer|doctor" # contains either term in field
f = Text("job") % "engineer doctor" # contains both terms in field
"""
self._set_value(other, self.SUPPORTED_VAL_TYPES, FilterOperator.LIKE)
return FilterExpression(str(self))
[docs]
def __str__(self) -> str:
"""Return the Redis Query string for the Text filter"""
if not self._value:
return "*"
return self.OPERATOR_MAP[self._operator] % (
self._field,
self._value,
)
[docs]
class FilterExpression:
"""A FilterExpression is a logical combination of filters in RedisVL.
FilterExpressions can be combined using the & and | operators to create
complex expressions that evaluate to the Redis Query language.
This presents an interface by which users can create complex queries
without having to know the Redis Query language.
.. code-block:: python
from redisvl.query.filter import Tag, Num
brand_is_nike = Tag("brand") == "nike"
price_is_over_100 = Num("price") < 100
f = brand_is_nike & price_is_over_100
print(str(f))
>>> (@brand:{nike} @price:[-inf (100)])
This can be combined with the VectorQuery class to create a query:
.. code-block:: python
from redisvl.query import VectorQuery
v = VectorQuery(
vector=[0.1, 0.1, 0.5, ...],
vector_field_name="product_embedding",
return_fields=["product_id", "brand", "price"],
filter_expression=f,
)
Note:
Filter expressions are typically not called directly. Instead they are
built by combining filter statements using the & and | operators.
"""
def __init__(
self,
_filter: Optional[str] = None,
operator: Optional[FilterOperator] = None,
left: Optional["FilterExpression"] = None,
right: Optional["FilterExpression"] = None,
):
self._filter = _filter
self._operator = operator
self._left = left
self._right = right
def __and__(self, other) -> "FilterExpression":
return FilterExpression(operator=FilterOperator.AND, left=self, right=other)
def __or__(self, other) -> "FilterExpression":
return FilterExpression(operator=FilterOperator.OR, left=self, right=other)
@staticmethod
def format_expression(left, right, operator_str) -> str:
_left, _right = str(left), str(right)
if _left == _right == "*":
return _left
if _left == "*" != _right:
return _right
if _right == "*" != _left:
return _left
return f"({_left}{operator_str}{_right})"
def __str__(self) -> str:
# top level check that allows recursive calls to __str__
if not self._filter and not self._operator:
raise ValueError("Improperly initialized FilterExpression")
# if theres an operator, combine expressions accordingly
if self._operator:
if not isinstance(self._left, FilterExpression) or not isinstance(
self._right, FilterExpression
):
raise TypeError(
"Improper combination of filters. Both left and right should be type FilterExpression"
)
operator_str = " | " if self._operator == FilterOperator.OR else " "
return self.format_expression(self._left, self._right, operator_str)
# check that base case, the filter is set
if not self._filter:
raise ValueError("Improperly initialized FilterExpression")
return self._filter
