forked from Archives/langchain
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
69 lines
2.1 KiB
Python
69 lines
2.1 KiB
Python
"""Functionality for loading chains."""
|
|
import json
|
|
from pathlib import Path
|
|
from typing import Union
|
|
|
|
import yaml
|
|
|
|
from langchain.chains.base import Chain
|
|
from langchain.chains.llm import LLMChain
|
|
from langchain.llms.loading import load_llm, load_llm_from_config
|
|
from langchain.prompts.loading import load_prompt, load_prompt_from_config
|
|
|
|
|
|
def _load_llm_chain(config: dict) -> LLMChain:
|
|
"""Load LLM chain from config dict."""
|
|
if "llm" in config:
|
|
llm_config = config.pop("llm")
|
|
llm = load_llm_from_config(llm_config)
|
|
elif "llm_path" in config:
|
|
llm = load_llm(config.pop("llm_path"))
|
|
else:
|
|
raise ValueError("One of `llm` or `llm_config` must be present.")
|
|
|
|
if "prompt" in config:
|
|
prompt_config = config.pop("prompt")
|
|
prompt = load_prompt_from_config(prompt_config)
|
|
elif "prompt_path" in config:
|
|
prompt = load_prompt(config.pop("prompt_path"))
|
|
else:
|
|
raise ValueError("One of `prompt` or `prompt_path` must be present.")
|
|
|
|
return LLMChain(llm=llm, prompt=prompt, **config)
|
|
|
|
|
|
type_to_loader_dict = {"llm_chain": _load_llm_chain}
|
|
|
|
|
|
def load_chain_from_config(config: dict) -> Chain:
|
|
"""Load chain from Config Dict."""
|
|
if "_type" not in config:
|
|
raise ValueError("Must specify an chain Type in config")
|
|
config_type = config.pop("_type")
|
|
|
|
if config_type not in type_to_loader_dict:
|
|
raise ValueError(f"Loading {config_type} chain not supported")
|
|
|
|
chain_loader = type_to_loader_dict[config_type]
|
|
return chain_loader(config)
|
|
|
|
|
|
def load_chain(file: Union[str, Path]) -> Chain:
|
|
"""Load chain from file."""
|
|
# Convert file to Path object.
|
|
if isinstance(file, str):
|
|
file_path = Path(file)
|
|
else:
|
|
file_path = file
|
|
# Load from either json or yaml.
|
|
if file_path.suffix == ".json":
|
|
with open(file_path) as f:
|
|
config = json.load(f)
|
|
elif file_path.suffix == ".yaml":
|
|
with open(file_path, "r") as f:
|
|
config = yaml.safe_load(f)
|
|
else:
|
|
raise ValueError("File type must be json or yaml")
|
|
# Load the chain from the config now.
|
|
return load_chain_from_config(config)
|