langchain学习（四）_langchain invoke

Interface官方文档

https://python.langchain.com/docs/expression_language/interfaceTo make it as easy as possible to create custom chains, we’vehttps://python.langchain.com/docs/expression_language/interface

1、langchain采用了一个叫“Runnable” 的标准协议/接口，给用户组合部件（component）形成chains，标准化的接口还包括：

stream：流式（实时）返回结果

invoke：单输入

batch：通过列表进行多输入

同时提供以上接口的异步方式

2、component的输入输出类型表

3、并行请求

方式1通过RunnableParallel

from langchain.prompts import ChatPromptTemplate
from langchain_core.runnables import RunnableParallel
from time import process_time
process_time()
chain1 = ChatPromptTemplate.from_template("tell me a joke about {topic}")
chain2 = (
    ChatPromptTemplate.from_template("write a short (2 line) poem about {topic}")
)
combined = RunnableParallel(joke=chain1, poem=chain2)
print(process_time())

方式2通过batch接口

combined.batch([{"topic": "bears"}, {"topic": "cats"}])