Source code for langchain.chains.api.base
"""Chain that makes API calls and summarizes the responses to answer a question."""
from __future__ import annotations
from typing import Any, Dict, List, Optional
from langchain.callbacks.manager import (
    AsyncCallbackManagerForChainRun,
    CallbackManagerForChainRun,
)
from langchain.chains.api.prompt import API_RESPONSE_PROMPT, API_URL_PROMPT
from langchain.chains.base import Chain
from langchain.chains.llm import LLMChain
from langchain.pydantic_v1 import Field, root_validator
from langchain.schema import BasePromptTemplate
from langchain.schema.language_model import BaseLanguageModel
from langchain.utilities.requests import TextRequestsWrapper
[docs]class APIChain(Chain):
    """Chain that makes API calls and summarizes the responses to answer a question."""
    api_request_chain: LLMChain
    api_answer_chain: LLMChain
    requests_wrapper: TextRequestsWrapper = Field(exclude=True)
    api_docs: str
    question_key: str = "question"  #: :meta private:
    output_key: str = "output"  #: :meta private:
    @property
    def input_keys(self) -> List[str]:
        """Expect input key.
        :meta private:
        """
        return [self.question_key]
    @property
    def output_keys(self) -> List[str]:
        """Expect output key.
        :meta private:
        """
        return [self.output_key]
    @root_validator(pre=True)
    def validate_api_request_prompt(cls, values: Dict) -> Dict:
        """Check that api request prompt expects the right variables."""
        input_vars = values["api_request_chain"].prompt.input_variables
        expected_vars = {"question", "api_docs"}