langchain/libs/community/langchain_community/query_constructors/milvus.py
Eugene Yurtsev f92006de3c
multiple: langchain 0.2 in master (#21191)
0.2rc 

migrations

- [x] Move memory
- [x] Move remaining retrievers
- [x] graph_qa chains
- [x] some dependency from evaluation code potentially on math utils
- [x] Move openapi chain from `langchain.chains.api.openapi` to
`langchain_community.chains.openapi`
- [x] Migrate `langchain.chains.ernie_functions` to
`langchain_community.chains.ernie_functions`
- [x] migrate `langchain/chains/llm_requests.py` to
`langchain_community.chains.llm_requests`
- [x] Moving `langchain_community.cross_enoders.base:BaseCrossEncoder`
->
`langchain_community.retrievers.document_compressors.cross_encoder:BaseCrossEncoder`
(namespace not ideal, but it needs to be moved to `langchain` to avoid
circular deps)
- [x] unit tests langchain -- add pytest.mark.community to some unit
tests that will stay in langchain
- [x] unit tests community -- move unit tests that depend on community
to community
- [x] mv integration tests that depend on community to community
- [x] mypy checks

Other todo

- [x] Make deprecation warnings not noisy (need to use warn deprecated
and check that things are implemented properly)
- [x] Update deprecation messages with timeline for code removal (likely
we actually won't be removing things until 0.4 release) -- will give
people more time to transition their code.
- [ ] Add information to deprecation warning to show users how to
migrate their code base using langchain-cli
- [ ] Remove any unnecessary requirements in langchain (e.g., is
SQLALchemy required?)

---------

Co-authored-by: Erick Friis <erick@langchain.dev>
2024-05-08 16:46:52 -04:00

104 lines
3.3 KiB
Python

"""Logic for converting internal query language to a valid Milvus query."""
from typing import Tuple, Union
from langchain_core.structured_query import (
Comparator,
Comparison,
Operation,
Operator,
StructuredQuery,
Visitor,
)
COMPARATOR_TO_BER = {
Comparator.EQ: "==",
Comparator.GT: ">",
Comparator.GTE: ">=",
Comparator.LT: "<",
Comparator.LTE: "<=",
Comparator.IN: "in",
Comparator.LIKE: "like",
}
UNARY_OPERATORS = [Operator.NOT]
def process_value(value: Union[int, float, str], comparator: Comparator) -> str:
"""Convert a value to a string and add double quotes if it is a string.
It required for comparators involving strings.
Args:
value: The value to convert.
comparator: The comparator.
Returns:
The converted value as a string.
"""
#
if isinstance(value, str):
if comparator is Comparator.LIKE:
# If the comparator is LIKE, add a percent sign after it for prefix matching
# and add double quotes
return f'"{value}%"'
else:
# If the value is already a string, add double quotes
return f'"{value}"'
else:
# If the value is not a string, convert it to a string without double quotes
return str(value)
class MilvusTranslator(Visitor):
"""Translate Milvus internal query language elements to valid filters."""
"""Subset of allowed logical operators."""
allowed_operators = [Operator.AND, Operator.NOT, Operator.OR]
"""Subset of allowed logical comparators."""
allowed_comparators = [
Comparator.EQ,
Comparator.GT,
Comparator.GTE,
Comparator.LT,
Comparator.LTE,
Comparator.IN,
Comparator.LIKE,
]
def _format_func(self, func: Union[Operator, Comparator]) -> str:
self._validate_func(func)
value = func.value
if isinstance(func, Comparator):
value = COMPARATOR_TO_BER[func]
return f"{value}"
def visit_operation(self, operation: Operation) -> str:
if operation.operator in UNARY_OPERATORS and len(operation.arguments) == 1:
operator = self._format_func(operation.operator)
return operator + "(" + operation.arguments[0].accept(self) + ")"
elif operation.operator in UNARY_OPERATORS:
raise ValueError(
f'"{operation.operator.value}" can have only one argument in Milvus'
)
else:
args = [arg.accept(self) for arg in operation.arguments]
operator = self._format_func(operation.operator)
return "(" + (" " + operator + " ").join(args) + ")"
def visit_comparison(self, comparison: Comparison) -> str:
comparator = self._format_func(comparison.comparator)
processed_value = process_value(comparison.value, comparison.comparator)
attribute = comparison.attribute
return "( " + attribute + " " + comparator + " " + processed_value + " )"
def visit_structured_query(
self, structured_query: StructuredQuery
) -> Tuple[str, dict]:
if structured_query.filter is None:
kwargs = {}
else:
kwargs = {"expr": structured_query.filter.accept(self)}
return structured_query.query, kwargs