AttributeError：'Web3‘对象没有属性middleware_stack

Question

• web3.py版本：5.0.1，Python：3.6.3

下面的代码是在web3==4.9.2上运行的，它不适用于web3==5.0.1。我收到以下错误：

web3.middleware_stack.inject(geth_poa_middleware, layer=0)
AttributeError: 'Web3' object has no attribute 'middleware_stack'

示例代码：

#!/usr/bin/env python3
from web3 import Web3
from web3.providers.rpc import HTTPProvider
from web3 import Web3, IPCProvider

web3 = Web3(IPCProvider('/private/geth.ipc'))
from web3.middleware import geth_poa_middleware
# inject the poa compatibility middleware to the innermost layer
web3.middleware_stack.inject(geth_poa_middleware, layer=0)
from web3.shh import Shh
Shh.attach(web3, 'shh')

Answer 1

Web3.middleware_onion.add(middleware, name=None)

用web3.middleware_stack.inject(geth_poa_middleware, layer=0)代替web3.middleware_onion.inject(geth_poa_middleware, layer=0)解决了这个问题。