faiss_rag_enterprise/llama_index/evaluation/guideline.py

121 lines
4.2 KiB
Python

"""Guideline evaluation."""
import asyncio
import logging
from typing import Any, Optional, Sequence, Union, cast
from llama_index import ServiceContext
from llama_index.bridge.pydantic import BaseModel, Field
from llama_index.evaluation.base import BaseEvaluator, EvaluationResult
from llama_index.output_parsers import PydanticOutputParser
from llama_index.prompts import BasePromptTemplate, PromptTemplate
from llama_index.prompts.mixin import PromptDictType
logger = logging.getLogger(__name__)
DEFAULT_GUIDELINES = (
"The response should fully answer the query.\n"
"The response should avoid being vague or ambiguous.\n"
"The response should be specific and use statistics or numbers when possible.\n"
)
DEFAULT_EVAL_TEMPLATE = PromptTemplate(
"Here is the original query:\n"
"Query: {query}\n"
"Critique the following response based on the guidelines below:\n"
"Response: {response}\n"
"Guidelines: {guidelines}\n"
"Now please provide constructive criticism.\n"
)
class EvaluationData(BaseModel):
passing: bool = Field(description="Whether the response passes the guidelines.")
feedback: str = Field(
description="The feedback for the response based on the guidelines."
)
class GuidelineEvaluator(BaseEvaluator):
"""Guideline evaluator.
Evaluates whether a query and response pair passes the given guidelines.
This evaluator only considers the query string and the response string.
Args:
service_context(Optional[ServiceContext]):
The service context to use for evaluation.
guidelines(Optional[str]): User-added guidelines to use for evaluation.
Defaults to None, which uses the default guidelines.
eval_template(Optional[Union[str, BasePromptTemplate]] ):
The template to use for evaluation.
"""
def __init__(
self,
service_context: Optional[ServiceContext] = None,
guidelines: Optional[str] = None,
eval_template: Optional[Union[str, BasePromptTemplate]] = None,
) -> None:
self._service_context = service_context or ServiceContext.from_defaults()
self._guidelines = guidelines or DEFAULT_GUIDELINES
self._eval_template: BasePromptTemplate
if isinstance(eval_template, str):
self._eval_template = PromptTemplate(eval_template)
else:
self._eval_template = eval_template or DEFAULT_EVAL_TEMPLATE
self._output_parser = PydanticOutputParser(output_cls=EvaluationData)
self._eval_template.output_parser = self._output_parser
def _get_prompts(self) -> PromptDictType:
"""Get prompts."""
return {
"eval_template": self._eval_template,
}
def _update_prompts(self, prompts: PromptDictType) -> None:
"""Update prompts."""
if "eval_template" in prompts:
self._eval_template = prompts["eval_template"]
async def aevaluate(
self,
query: Optional[str] = None,
response: Optional[str] = None,
contexts: Optional[Sequence[str]] = None,
sleep_time_in_seconds: int = 0,
**kwargs: Any,
) -> EvaluationResult:
"""Evaluate whether the query and response pair passes the guidelines."""
del contexts # Unused
del kwargs # Unused
if query is None or response is None:
raise ValueError("query and response must be provided")
logger.debug("prompt: %s", self._eval_template)
logger.debug("query: %s", query)
logger.debug("response: %s", response)
logger.debug("guidelines: %s", self._guidelines)
await asyncio.sleep(sleep_time_in_seconds)
eval_response = await self._service_context.llm.apredict(
self._eval_template,
query=query,
response=response,
guidelines=self._guidelines,
)
eval_data = self._output_parser.parse(eval_response)
eval_data = cast(EvaluationData, eval_data)
return EvaluationResult(
query=query,
response=response,
passing=eval_data.passing,
score=1.0 if eval_data.passing else 0.0,
feedback=eval_data.feedback,
)