redis-om-python/redis_om/model/query_resolver.py

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from collections import Sequence
from typing import Any, Dict, List, Mapping, Union
2021-10-22 15:36:15 +02:00
from redis_om.model.model import Expression
class LogicalOperatorForListOfExpressions(Expression):
operator: str = ""
def __init__(self, *expressions: Expression):
self.expressions = list(expressions)
@property
def query(self) -> Mapping[str, List[Expression]]:
if not self.expressions:
raise AttributeError("At least one expression must be provided")
# TODO: This needs to return a RediSearch string.
# Use the values in each expression object to build the string.
# Determine the type of query based on the field (numeric range,
# tag field, etc.).
return {self.operator: self.expressions}
class Or(LogicalOperatorForListOfExpressions):
"""
Logical OR query operator
Example:
```python
class Product(JsonModel):
price: float
category: str
Or(Product.price < 10, Product.category == "Sweets")
```
Will return RediSearch query string like:
```
(@price:[-inf 10]) | (@category:{Sweets})
```
"""
operator = "|"
class And(LogicalOperatorForListOfExpressions):
"""
Logical AND query operator
Example:
```python
class Product(Document):
price: float
category: str
And(Product.price < 10, Product.category == "Sweets")
```
Will return a query string like:
```
(@price:[-inf 10]) (@category:{Sweets})
```
Note that in RediSearch, AND is implied with multiple terms.
"""
operator = " "
class Not(LogicalOperatorForListOfExpressions):
"""
Logical NOT query operator
Example:
```python
class Product(Document):
price: float
category: str
Not(Product.price<10, Product.category=="Sweets")
```
Will return a query string like:
```
-(@price:[-inf 10]) -(@category:{Sweets})
```
"""
@property
def query(self):
return "-(expression1) -(expression2)"
class QueryResolver:
def __init__(self, *expressions: Expression):
self.expressions = expressions
def resolve(self) -> str:
"""Resolve expressions to a RediSearch query string."""