Source code for langchain.retrievers.self_query.pgvector

from typing import Dict, Tuple, Union

from langchain_core.structured_query import (
    Comparator,
    Comparison,
    Operation,
    Operator,
    StructuredQuery,
    Visitor,
)


[docs]class PGVectorTranslator(Visitor): """Translate `PGVector` internal query language elements to valid filters.""" allowed_operators = [Operator.AND, Operator.OR] """Subset of allowed logical operators.""" allowed_comparators = [ Comparator.EQ, Comparator.NE, Comparator.GT, Comparator.LT, Comparator.IN, Comparator.NIN, Comparator.CONTAIN, Comparator.LIKE, ] """Subset of allowed logical comparators.""" def _format_func(self, func: Union[Operator, Comparator]) -> str: self._validate_func(func) return f"{func.value}"
[docs] def visit_operation(self, operation: Operation) -> Dict: args = [arg.accept(self) for arg in operation.arguments] return {self._format_func(operation.operator): args}
[docs] def visit_comparison(self, comparison: Comparison) -> Dict: return { comparison.attribute: { self._format_func(comparison.comparator): comparison.value } }
[docs] def visit_structured_query( self, structured_query: StructuredQuery ) -> Tuple[str, dict]: if structured_query.filter is None: kwargs = {} else: kwargs = {"filter": structured_query.filter.accept(self)} return structured_query.query, kwargs