59 lines
1.9 KiB
Python
59 lines
1.9 KiB
Python
|
from __future__ import annotations
|
||
|
|
|
||
|
|
from typing import Any
|
||
|
|
|
||
|
|
from langchain_core.output_parsers import BaseOutputParser
|
||
|
|
from langchain_core.utils import pre_init
|
||
|
|
from typing_extensions import override
|
||
|
|
|
||
|
|
_MIN_PARSERS = 2
|
||
|
|
|
||
|
|
|
||
|
|
class CombiningOutputParser(BaseOutputParser[dict[str, Any]]):
|
||
|
|
"""Combine multiple output parsers into one."""
|
||
|
|
|
||
|
|
parsers: list[BaseOutputParser]
|
||
|
|
|
||
|
|
@classmethod
|
||
|
|
@override
|
||
|
|
def is_lc_serializable(cls) -> bool:
|
||
|
|
return True
|
||
|
|
|
||
|
|
@pre_init
|
||
|
|
def validate_parsers(cls, values: dict[str, Any]) -> dict[str, Any]:
|
||
|
|
"""Validate the parsers."""
|
||
|
|
parsers = values["parsers"]
|
||
|
|
if len(parsers) < _MIN_PARSERS:
|
||
|
|
msg = "Must have at least two parsers"
|
||
|
|
raise ValueError(msg)
|
||
|
|
for parser in parsers:
|
||
|
|
if parser._type == "combining": # noqa: SLF001
|
||
|
|
msg = "Cannot nest combining parsers"
|
||
|
|
raise ValueError(msg)
|
||
|
|
if parser._type == "list": # noqa: SLF001
|
||
|
|
msg = "Cannot combine list parsers"
|
||
|
|
raise ValueError(msg)
|
||
|
|
return values
|
||
|
|
|
||
|
|
@property
|
||
|
|
def _type(self) -> str:
|
||
|
|
"""Return the type key."""
|
||
|
|
return "combining"
|
||
|
|
|
||
|
|
def get_format_instructions(self) -> str:
|
||
|
|
"""Instructions on how the LLM output should be formatted."""
|
||
|
|
initial = f"For your first output: {self.parsers[0].get_format_instructions()}"
|
||
|
|
subsequent = "\n".join(
|
||
|
|
f"Complete that output fully. Then produce another output, separated by two newline characters: {p.get_format_instructions()}" # noqa: E501
|
||
|
|
for p in self.parsers[1:]
|
||
|
|
)
|
||
|
|
return f"{initial}\n{subsequent}"
|
||
|
|
|
||
|
|
def parse(self, text: str) -> dict[str, Any]:
|
||
|
|
"""Parse the output of an LLM call."""
|
||
|
|
texts = text.split("\n\n")
|
||
|
|
output = {}
|
||
|
|
for txt, parser in zip(texts, self.parsers, strict=False):
|
||
|
|
output.update(parser.parse(txt.strip()))
|
||
|
|
return output
|